Energy Combustion

Energy Combustion, Ahmedabad suppliers of Siemens make burner servomotor / Siemens Actuators.
 
The Siemens SQM45...B9 version is the upgraded, modern successor to the older A9 series. While they are physically and functionally interchangeable, the "B9" version features a major internal technology upgrade.

1. The Key Difference: Hall Sensor vs. Potentiometer 

• A9 Version: Used a double conductive plastic potentiometer for position feedback. Potentiometers are mechanical and can wear out over thousands of cycles.

• B9 Version: Uses a Hall Effect sensor (magnetic) for position feedback. Since there is no physical contact, it does not wear out, leading to significantly higher reliability and a longer service life.

2. Full Specifications (SQM45...B9) 3. Model Specifics (Shaft Types)

The B9 version is available with the two standard shaft configurations:

• SQM45.291B9: Features a $10\text{ mm}$ shaft with a Woodruff key. (Replaces SQM45.291A9)

• SQM45.295B9: Features a $10\text{ mm}$ D-shaped shaft (flat side). (Replaces SQM45.295A9)

4. Installation & Compatibility

• Direct Replacement: The B9 is a "drop-in" replacement for the A9. No mechanical modifications are usually required.

• Electrical Connection: Uses the same RAST3.5 edge connectors.

• Initialization: When installed for the first time or replaced, the LMV5 system will automatically recognize the new actuator. You must perform a "Reference Run" via the AZL52 display to calibrate the zero-point.

• Construction: Pressure die-cast aluminum lower housing with a heat-resistant, impact-proof black plastic cover.

5. Why the B9 is Better

In high-cycle industrial applications, the original A9 potentiometers could eventually develop "dead spots" or signal noise. By moving to a Hall sensor, Siemens eliminated the most common failure point in these actuators, making the B9 version essential for modern low-maintenance burner management. 

ENERGY COMBUSTION , Ahmedabad supplier of SIEMENS make SQM series Burner Servomotor.

The Siemens SQM48.497 is a high-performance burner servo motor (actuator) designed for precise air damper and fuel valve control in medium to larger capacity industrial oil and gas burners and thermal process plants. It is primarily used with the Siemens LMV5 series electronic ratio control systems. 
Note that the SQM48.497B9 is the current model and a replacement for the older SQM48.497A9 model. 
Key Specifications (Model SQM48.497B9)

Like WEISHAUPT BURNER , ECOFLAME BURNER , BENTONE BURNER , RIELLO BURNER , BALTUR BURNER , CUNOD BURNER.

The Siemens SQM40 and SQM41 series are electromotoric actuators designed for driving gas or air dampers, as well as oil control valves, on medium to large burners. These actuators are highly versatile, offering versions for both Linkageless (LMV) systems and Standalone Modulating systems.

1. SQM40 vs. SQM41 Series

While they look nearly identical, the primary difference is the torque and rotation direction capability:

2. All Model Variants

The SQM40 series is divided into three main control categories based on the internal electronics:

A. Stepper Motor Versions (For LMV2/LMV3 Systems)

These are controlled via the system's bus and offer $0.1^\circ$ precision.

• SQM40.244...

• SQM41.244...

Key Detail: These do not have internal cams; the LMV controller handles all positioning electronically.

B. Analog Versions (4-20 mA / 0-10 V)

These include an integrated electronic module that allows for modulating control without a complex burner management system.

• SQM40.245...

• SQM41.245...

Key Detail: Used for standalone industrial applications where a PLC or RWF55 temperature controller provides the setpoint.

C. 3-Position Versions (Relay/Contact)

Standard versions used for "Open/Stop/Close" logic or High/Low fire control.

• SQM40.241...

• SQM41.241...

3. Technical Specifications 4. Key Functional Features

• Double-Ended Shaft: The SQM40 often features a drive shaft extending from both the front and rear, allowing for flexible mounting or the addition of external potentiometers.

• Integrated Potentiometer: Analog versions usually include a $1 \text{ k}\Omega$ or $5 \text{ k}\Omega$ conductive plastic potentiometer for high-accuracy position feedback.

• Robust Housing: The body is made of die-cast aluminum, providing superior durability compared to the plastic SQN series.

• Adjustable Cams (Non-stepper models): Standard versions use mechanical cams similar to the SQN series but with higher-precision microswitches.

5. Wiring and Connections

The SQM40 series uses RAST connectors or screw terminals depending on the variant. Stepper versions use the RAST2.5 system common to the LMV series, while standalone versions use standard PG cable glands.

6. Selection Tip

When replacing an SQM40, pay close attention to the shaft end. Common types include:

1. Woodruff Key (91): For heavy-duty industrial linkages.

2. D-Shape (92): Standard flat-sided shaft for set-screws.

3. Square (93): For specialized mechanical adapters.

ENERGY COMBUSTION, Ahmedabad supplier of all products of SIEMENS for Industrial Oil and Gas Burners.

The Siemens SQM10 series is an electromotoric actuator designed for the precise control of gas and air dampers on medium to large burners. Unlike the compact SQN series, the SQM10 features a robust die-cast aluminum housing and high-torque gears, making it suitable for heavy-duty industrial environments.

1. SQM10 Model Variants

The model number specifies the running time, torque, and the internal circuit configuration. The SQM10 is a clockwise (CW) rotating unit.

Note: Suffixes like .15562 usually include a built-in potentiometer for position feedback ($1000\ \Omega$).

2. Technical Specifications 3. Internal Components & Adjustments

The SQM10 is powered by a reversible synchronous motor and uses a traditional cam-and-switch system for positioning.

• Cams: The unit contains multiple adjustable cams (Red, Blue, Orange, etc.) that define the travel limits and ignition points.

• Potentiometer (Optional): Many SQM10 units are fitted with a conductive plastic potentiometer to provide a $4\dots 20\text{ mA}$ or $0\dots 10\text{ V}$ feedback signal to an external controller (like the Siemens RWF55).

• Manual Release: There is a manual decoupling lever that allows you to rotate the shaft by hand for mechanical alignment during installation.

4. Key Applications

The SQM10 is the preferred choice for:

• Modulating Burners: Where the air damper must constantly adjust to maintain the correct oxygen levels.

• Large Air Dampers: Where the torque required exceeds the capability of the plastic SQN series.

• Industrial Kilns and Ovens: Where durability and high IP ratings are required.

5. Selection and Replacement

If you are replacing an SQM10, you must check the Suffix:

1. Potentiometer: If your existing unit has a potentiometer (used for feedback), the new one must have the exact same resistance value ($1000\ \Omega$ is standard).

2. Running Time: Ensure the $14\text{s}$ vs $29\text{s}$ running time matches. A mismatched running time can destabilize the burner's PID control loop.

3. Shaft Orientation: While the SQM10 is CW, ensure your mechanical linkage is compatible with the "Home" position. 

Siemens burner servomotors (actuators) are the industry standard for controlling the air-to-fuel ratio in combustion systems. They are categorized into two main technologies: Electromechanical (SQN) for traditional linkage-based burners and Electronic/Stepper (SQM) for modern linkageless (LMV) systems.

1. SQN Series (Electromechanical)

The SQN series uses reversible synchronous motors with adjustable mechanical cams.¹ They are used with controllers like the LME, LMO, or LGB.²

+1

 

Details:

• Adjustment: Uses color-coded cams (Red: Max, Blue: Min, Orange: Ignition).

• Manual Release: Features a clutch to disengage gears for manual commissioning.

• Protection: Typically IP40.

2. SQM Series (Electronic & Stepper)

The SQM series is more robust, offering higher torque and precision. They are divided into "Analog" (cams/potentiometers) and "Digital" (CAN bus stepper).

A. Analog/Modulating Models (SQM10, 20, 50)

Used for standalone modulating control (e.g., with RWF55) or traditional linkages.

• SQM10/20: Up to $20$ Nm torque. Aluminum housing.

• SQM50/53/56: The industrial workhorses. Torque up to $40$ Nm. $100\%$ duty cycle.

B. Linkageless Stepper Models (SQM33, 45, 48, 91)

Specifically for LMV2/3 and LMV5 systems. No mechanical cams; positioning is handled via CAN bus.

3. Technical Comparison: SQN vs. SQM 4. Key Selection Factors

When choosing or replacing a Siemens servomotor, you must verify:

1. Direction of Rotation: Clockwise (e.g., SQN30) vs. Counter-clockwise (e.g., SQN31).

2. Running Time: $90^\circ$ travel must match the burner controller's sequence (e.g., $12$s vs $30$s).

3. Shaft Type: Square, D-shape, or Woodruff key.

4. Interface: 3-position relay (SQN) vs. CAN bus (SQM33/45/48) vs. $4-20$ mA (SQM40/41). 

The Siemens SQN30 series (and its counterpart, the SQN31) consists of small electromotoric actuators designed to drive gas or air dampers on small to medium-sized burners.¹ They are highly reliable and are typically controlled by burner management systems like the LGB, LME, or LMO.

1. Model Differentiation

The primary difference between the two main series is the direction of rotation:

• SQN30: Clockwise (CW) rotation (when looking at the shaft).

• SQN31: Counter-clockwise (CCW) rotation (when looking at the shaft).

2. Technical Specifications

3. Internal Features & Components

The SQN30 is a "Smart" mechanical actuator  containing a reversible synchronous motor and a specialized gear train.

• Adjustable Cams: It contains multiple cams (usually color-coded) that trigger microswitches to define:

• High-Fire (Max) Position: Usually a Red cam.

• Low-Fire (Min) Position: Usually a Blue cam.

• • Ignition/Auxiliary Positions: Usually Orange or Black cams.

• Manual Disengagement: A small lever or push-button allows the gear train to be decoupled so the shaft can be turned by hand during commissioning.

• Shaft Options: Typically features a 10 mm diameter shaft with a flat side ("D-shape") or a square shaft depending on the specific burner assembly requirement.

4. Control Wiring

The SQN30 series supports various control methods depending on the terminal configuration (versions A, B, or C):

1. 2-Stage Control: Moves between a pre-set Minimum and Maximum position based on a single-pole switch .

2. Modulating Control: When used with a PID controller (like the Siemens RWF series), the actuator can be stopped at any intermediate position to precisely match the heat demand.

5. Maintenance and Replacement

 

• Lubrication: The gear train is permanently lubricated and does not require maintenance.

• Replacement Warning: When replacing an SQN30, ensure the running time  4.5s vs 30s) matches exactly. If the running time is too slow, the burner controller may time out and go into "Air Pressure Failure" or "Sequence Error."

The Siemens SQN30 series (and its counterpart, the SQN31) consists of small electromotoric actuators designed to drive gas or air dampers on small to medium-sized burners.¹ They are highly reliable and are typically controlled by burner management systems like the LGB, LME, or LMO.

1. Model Differentiation

The primary difference between the two main series is the direction of rotation:

• SQN30: Clockwise (CW) rotation (when looking at the shaft).

• SQN31: Counter-clockwise (CCW) rotation (when looking at the shaft).

2. Technical Specifications

3. Internal Features & Components

The SQN30 is a "Smart" mechanical actuator  containing a reversible synchronous motor and a specialized gear train.

• Adjustable Cams: It contains multiple cams (usually color-coded) that trigger microswitches to define:

• High-Fire (Max) Position: Usually a Red cam.

• Low-Fire (Min) Position: Usually a Blue cam.

• • Ignition/Auxiliary Positions: Usually Orange or Black cams.

• Manual Disengagement: A small lever or push-button allows the gear train to be decoupled so the shaft can be turned by hand during commissioning.

• Shaft Options: Typically features a 10 mm diameter shaft with a flat side ("D-shape") or a square shaft depending on the specific burner assembly requirement.

4. Control Wiring

The SQN30 series supports various control methods depending on the terminal configuration (versions A, B, or C):

1. 2-Stage Control: Moves between a pre-set Minimum and Maximum position based on a single-pole switch .

2. Modulating Control: When used with a PID controller (like the Siemens RWF series), the actuator can be stopped at any intermediate position to precisely match the heat demand.

5. Maintenance and Replacement

 

• Lubrication: The gear train is permanently lubricated and does not require maintenance.

• Replacement Warning: When replacing an SQN30, ensure the running time  4.5s vs 30s) matches exactly. If the running time is too slow, the burner controller may time out and go into "Air Pressure Failure" or "Sequence Error."

The Siemens SQN30 series (and its counterpart, the SQN31) consists of small electromotoric actuators designed to drive gas or air dampers on small to medium-sized burners.¹ They are highly reliable and are typically controlled by burner management systems like the LGB, LME, or LMO.

1. Model Differentiation

The primary difference between the two main series is the direction of rotation:

• SQN30: Clockwise (CW) rotation (when looking at the shaft).

• SQN31: Counter-clockwise (CCW) rotation (when looking at the shaft).

2. Technical Specifications

3. Internal Features & Components

The SQN30 is a "Smart" mechanical actuator  containing a reversible synchronous motor and a specialized gear train.

• Adjustable Cams: It contains multiple cams (usually color-coded) that trigger microswitches to define:

• High-Fire (Max) Position: Usually a Red cam.

• Low-Fire (Min) Position: Usually a Blue cam.

• • Ignition/Auxiliary Positions: Usually Orange or Black cams.

• Manual Disengagement: A small lever or push-button allows the gear train to be decoupled so the shaft can be turned by hand during commissioning.

• Shaft Options: Typically features a 10 mm diameter shaft with a flat side ("D-shape") or a square shaft depending on the specific burner assembly requirement.

4. Control Wiring

The SQN30 series supports various control methods depending on the terminal configuration (versions A, B, or C):

1. 2-Stage Control: Moves between a pre-set Minimum and Maximum position based on a single-pole switch .

2. Modulating Control: When used with a PID controller (like the Siemens RWF series), the actuator can be stopped at any intermediate position to precisely match the heat demand.

5. Maintenance and Replacement

 

• Lubrication: The gear train is permanently lubricated and does not require maintenance.

• Replacement Warning: When replacing an SQN30, ensure the running time  4.5s vs 30s) matches exactly. If the running time is too slow, the burner controller may time out and go into "Air Pressure Failure" or "Sequence Error." 

The Siemens LKS series consists of electromotoric servomotors designed for the control of air dampers in oil and gas burners. While the SQN and SQM series are more common in high-end modulating systems, the LKS series is frequently used in smaller, residential, and commercial burners where simple two-stage or multi-stage air control is required.

1. Popular LKS Models

The LKS series is primarily divided by the type of burner (Gas vs. Oil) and the specific torque required.

2. Technical Specifications

• Mains Voltage: $200\dots 240\text{V AC}$ ($+10\% / -15\%$) or $100\dots 110\text{V AC}$.

• Frequency: $50\dots 60\text{ Hz}$.

• Power Consumption: Approx. $7\dots 12\text{ VA}$ (depending on torque).

• Duty Cycle: $50\dots 60\%$.

• Angle of Rotation: Adjustable up to $160^\circ$ (Factory set to $90^\circ$).

• Protection Class: IP44 (Standard) or IP54 with specific cable glands.

• Operating Temp: $-10\text{°C}$ to $+60\text{°C}$ (standard) or $-40\text{°C}$ for specialized oil versions.

3. Key Functional Features

• Synchronous Motor: Ensures constant running time regardless of load fluctuations or voltage drops.

• Adjustable Cams: Similar to the SQN series, LKS servomotors use mechanical cams to set:

  • High-Fire Position: Maximum air intake.

  • Low-Fire Position: Minimum air for idle or low-stage.

  • Ignition Position: Specific air-gap for safe lighting.

• Clutch Mechanism: Most LKS models have a manual disengagement button, allowing you to move the damper by hand to check for mechanical binding.

• Integrated Position Indicator: A visible scale on the side or top of the unit shows the current angular position of the shaft.

4. Selection and Replacement

When replacing an LKS motor, you must match the Shaft Type and Running Time exactly:

1. Shaft Types:

   • Square: Often $8\text{ mm}$ or $10\text{ mm}$.

   • D-Shape: Flat-sided shaft for set-screw mounting.

   • Internal Thread: Some specialized LKS 160 models use an internal thread for direct valve mounting.

2. Running Time: If the replacement motor is slower than the original, the burner controller may time out during the pre-purge cycle and cause a safety lockout.

5. Wiring Overview

The LKS typically uses a 7-pin or 10-pin terminal block.

• Terminal 1/2: Power Supply.

• Terminal 3: Control signal for "Open."

• Terminal 4: Control signal for "Close."

• Auxiliary Contacts: Used to feed back a "Purge Complete" signal to the burner controller.

The STE series (often designated as STE...) is a range of compact servomotors manufactured by Siemens (formerly Landis & Staefa). These actuators are specifically designed for air damper control in small to medium-sized burners and are frequently found on specialized burner brands like Elco, Weishaupt, and Riello.

The STE series is distinct from the SQN series due to its more rectangular, slim profile and its use in specific electronic ratio control applications.

1. Key Models and Versions

The STE series is primarily categorized by its control type (Analog/Relay vs. Digital/Bus) and the specific burner it was engineered for.

2. Technical Specifications 3. Core FeaturesA. Integrated Potentiometer

Unlike some SQN models where the potentiometer is optional, most STE models (especially the STE 50) feature a built-in, factory-calibrated potentiometer. This allows for continuous position feedback, which is essential for burners using electronic modulation rather than mechanical cams.

B. High Resolution

The STE series is known for its "step-free" or high-resolution movement. This makes it ideal for Low-NOx burners where the air damper must be positioned with sub-degree accuracy to maintain the correct flame chemistry.

C. Connection Interface

Many STE actuators do not use standard screw terminals. Instead, they often feature a pre-wired cable with a multi-pin plug (e.g., a 7-pin or 10-pin connector) designed to plug directly into the burner's main control board.

4. Maintenance and Troubleshooting

The STE series is largely maintenance-free, but it is sensitive to mechanical stress:

• The "Hunting" Issue: If the internal potentiometer wears out or gets dirty, the actuator may "hunt" (move back and forth rapidly). This usually requires a replacement of the entire unit as the potentiometers are often integrated into the circuit board.

• Shaft Alignment: Most STE models use a specific "D-shaped" or splined shaft. When replacing, you must ensure the shaft is indexed correctly to the damper linkage before powering the unit.

5. Comparison: STE vs. SQN

• Size: STE is thinner and more "box-like," making it suitable for compact burner housings.

• Electronics: STE models usually contain more sophisticated onboard electronics for signal processing compared to the purely mechanical microswitches of the SQN series.

• Customization: STE units are often "OEM-specific," meaning a Siemens STE for an Elco burner might not be interchangeable with one for a Weishaupt burner due to the internal software or plug wiring.

Energy Combustion, Ahmedabad importer and suppliers of Siemens make burner servomotor and other accessories for industrial applications.

The Siemens SQN90 is a series of compact, reversible electromotoric actuators used for the control of air and gas dampers on small to medium-sized burners. They are often used in conjunction with burner controllers like the LMO, LME, or LGB.

1. Primary SQN90 Models

The specific model suffix determines the direction of rotation, torque, and running time.

2. Technical Specifications

• Mains Voltage: $230\text{V AC}$ ($+10\% / -15\%$) or $115\text{V AC}$ variants.

• Frequency: $50\dots 60\text{ Hz}$.

• Power Consumption: Approx. $8\text{ VA}$.

• Angular Adjustment: Max $160\text{°}$ (standard factory set to $90\text{°}$).

• Protection Class: IP40 (when mounted correctly).

• Operating Temp: $-20\text{°C}$ to $+60\text{°C}$.

• Mounting Position: Optional (can be mounted horizontally or vertically).

• Shaft Type: $8\text{ mm}$ square shaft or "D" shaped shaft (depending on the version).

3. Internal Components & Adjustments

The SQN90 contains a set of adjustable cams that control the travel limits and auxiliary switches:

1. End Switches: Two switches (red and blue cams) define the Maximum Open and Minimum/Closed positions.

2. Auxiliary Switches: Up to three additional switches (black or grey cams) can be used to signal the burner controller when the damper has reached a specific intermediate position (e.g., "Ignition Position").

3. Manual Release: Most models feature a push-button or lever to disengage the gears, allowing the shaft to be turned by hand for setup and commissioning.

4. Key Features

• Reversible Motor: Unlike some older actuators, the SQN90 can move in both directions, allowing for precise modulating control when paired with a PID controller.

• Maintenance-Free: The gear train is permanently lubricated.

• Internal Potentiometer (Optional): Some versions can be fitted with a $1000\ \Omega$ or $5000\ \Omega$ potentiometer to provide feedback on the actual position to a remote display or PLC.

5. Wiring Overview

The actuator typically connects via a plug-in screw terminal block.

• Terminals 1 & 2: Usually the "Open" and "Close" control signals from the burner controller.

• Auxiliary Terminals: Used to "prove" to the burner controller that the air damper is fully open during the pre-purge phase.

Note: When replacing an SQN90, always check the direction of rotation (SQN90 = Clockwise, SQN91 = Counter-clockwise) as installing the wrong one can cause the burner to fail its pre-ignition safety checks. 

The Siemens SQN30 series (and its counterpart, the SQN31) consists of small electromotoric actuators designed to drive gas or air dampers on small to medium-sized burners.¹ They are highly reliable and are typically controlled by burner management systems like the LGB, LME, or LMO.

1. Model Differentiation

The primary difference between the two main series is the direction of rotation:

• SQN30: Clockwise (CW) rotation (when looking at the shaft).

• SQN31: Counter-clockwise (CCW) rotation (when looking at the shaft).

2. Technical Specifications

3. Internal Features & Components

The SQN30 is a "Smart" mechanical actuator  containing a reversible synchronous motor and a specialized gear train.

• Adjustable Cams: It contains multiple cams (usually color-coded) that trigger microswitches to define:

• High-Fire (Max) Position: Usually a Red cam.

• Low-Fire (Min) Position: Usually a Blue cam.

• • Ignition/Auxiliary Positions: Usually Orange or Black cams.

• Manual Disengagement: A small lever or push-button allows the gear train to be decoupled so the shaft can be turned by hand during commissioning.

• Shaft Options: Typically features a 10 mm diameter shaft with a flat side ("D-shape") or a square shaft depending on the specific burner assembly requirement.

4. Control Wiring

The SQN30 series supports various control methods depending on the terminal configuration (versions A, B, or C):

1. 2-Stage Control: Moves between a pre-set Minimum and Maximum position based on a single-pole switch .

2. Modulating Control: When used with a PID controller (like the Siemens RWF series), the actuator can be stopped at any intermediate position to precisely match the heat demand.

5. Maintenance and Replacement

 

• Lubrication: The gear train is permanently lubricated and does not require maintenance.

• Replacement Warning: When replacing an SQN30, ensure the running time  4.5s vs 30s) matches exactly. If the running time is too slow, the burner controller may time out and go into "Air Pressure Failure" or "Sequence Error."

The Siemens LKS series consists of electromotoric servomotors designed for the control of air dampers in oil and gas burners. While the SQN and SQM series are more common in high-end modulating systems, the LKS series is frequently used in smaller, residential, and commercial burners where simple two-stage or multi-stage air control is required.

1. Popular LKS Models

The LKS series is primarily divided by the type of burner (Gas vs. Oil) and the specific torque required.

2. Technical Specifications

• Mains Voltage: $200\dots 240\text{V AC}$ ($+10\% / -15\%$) or $100\dots 110\text{V AC}$.

• Frequency: $50\dots 60\text{ Hz}$.

• Power Consumption: Approx. $7\dots 12\text{ VA}$ (depending on torque).

• Duty Cycle: $50\dots 60\%$.

• Angle of Rotation: Adjustable up to $160^\circ$ (Factory set to $90^\circ$).

• Protection Class: IP44 (Standard) or IP54 with specific cable glands.

• Operating Temp: $-10\text{°C}$ to $+60\text{°C}$ (standard) or $-40\text{°C}$ for specialized oil versions.

3. Key Functional Features

• Synchronous Motor: Ensures constant running time regardless of load fluctuations or voltage drops.

• Adjustable Cams: Similar to the SQN series, LKS servomotors use mechanical cams to set:

  • High-Fire Position: Maximum air intake.

  • Low-Fire Position: Minimum air for idle or low-stage.

  • Ignition Position: Specific air-gap for safe lighting.

• Clutch Mechanism: Most LKS models have a manual disengagement button, allowing you to move the damper by hand to check for mechanical binding.

• Integrated Position Indicator: A visible scale on the side or top of the unit shows the current angular position of the shaft.

4. Selection and Replacement

When replacing an LKS motor, you must match the Shaft Type and Running Time exactly:

1. Shaft Types:

   • Square: Often $8\text{ mm}$ or $10\text{ mm}$.

   • D-Shape: Flat-sided shaft for set-screw mounting.

   • Internal Thread: Some specialized LKS 160 models use an internal thread for direct valve mounting.

2. Running Time: If the replacement motor is slower than the original, the burner controller may time out during the pre-purge cycle and cause a safety lockout.

5. Wiring Overview

The LKS typically uses a 7-pin or 10-pin terminal block.

• Terminal 1/2: Power Supply.

• Terminal 3: Control signal for "Open."

• Terminal 4: Control signal for "Close."

• Auxiliary Contacts: Used to feed back a "Purge Complete" signal to the burner controller.

The Siemens SQN70 (and its counterpart SQN71) is a range of electromotoric actuators designed to drive gas or air dampers on small to medium-sized burners.¹ They are often referred to as "high-torque" compact actuators compared to the SQN30 series and are typically used with burner controllers like the LME, LMO, or LGB.

 

1. SQN70 vs. SQN71: Direction of Rotation

• SQN70: Rotates Clockwise (CW) when looking at the drive shaft.

• SQN71: Rotates Counter-clockwise (CCW) when looking at the drive shaft.

2. All Models & Running Times

The model number determines the internal circuit (Version A, B, C, or D), the running time, and the torque.

Versions/Circuits

• Version A: For 2-stage control (High/Low) with no internal electronic ratio control.

• Version B: Primarily for use with controllers like the LME22.

• Version C: Designed for modulating control via a 3-position signal (Open/Stop/Close).

• Version D: Typically used with the LFL series or for specific industrial sequences.

3. Technical Specifications 4. Internal Components

The SQN70 series features a reversible synchronous motor and a gear train that can be manually disengaged for adjustment.²

 

The Cam Logic

• Red Cam: Maximum position (High-fire).

• Blue Cam: Minimum position (Closed or Low-fire).

• Orange/Black Cams: Auxiliary switches for "Ignition load" or "Release of fuel."

5. Key Features

• Maintenance-Free: The gear train is permanently lubricated.

• Manual Release: A push-button or lever on the housing allows the gears to be decoupled. This is vital for checking the mechanical linkage for binding without the motor running.

• Potentiometer Option: Some SQN70 models can be retrofitted with a $1,000\ \Omega$ potentiometer for position feedback to a PLC or display unit.

6. Maintenance and Selection Tip

1. Direction: (70 vs 71).

2. Running Time: (e.g., $2$s vs $30$s). If you install a slower actuator, the burner controller might go into lockout during the pre-purge transition.

3. Circuit Version: (e.g., A vs B). Using the wrong circuit version will result in the actuator not moving even when powered.  

The Siemens SQM10 series is an electromotoric actuator designed for the precise control of gas and air dampers on medium to large burners. Unlike the compact SQN series, the SQM10 features a robust die-cast aluminum housing and high-torque gears, making it suitable for heavy-duty industrial environments.

1. SQM10 Model Variants

The model number specifies the running time, torque, and the internal circuit configuration. The SQM10 is a clockwise (CW) rotating unit.

Note: Suffixes like .15562 usually include a built-in potentiometer for position feedback ($1000\ \Omega$).

2. Technical Specifications 3. Internal Components & Adjustments

The SQM10 is powered by a reversible synchronous motor and uses a traditional cam-and-switch system for positioning.

• Cams: The unit contains multiple adjustable cams (Red, Blue, Orange, etc.) that define the travel limits and ignition points.

• Potentiometer (Optional): Many SQM10 units are fitted with a conductive plastic potentiometer to provide a $4\dots 20\text{ mA}$ or $0\dots 10\text{ V}$ feedback signal to an external controller (like the Siemens RWF55).

• Manual Release: There is a manual decoupling lever that allows you to rotate the shaft by hand for mechanical alignment during installation.

4. Key Applications

The SQM10 is the preferred choice for:

• Modulating Burners: Where the air damper must constantly adjust to maintain the correct oxygen levels.

• Large Air Dampers: Where the torque required exceeds the capability of the plastic SQN series.

• Industrial Kilns and Ovens: Where durability and high IP ratings are required.

5. Selection and Replacement

If you are replacing an SQM10, you must check the Suffix:

1. Potentiometer: If your existing unit has a potentiometer (used for feedback), the new one must have the exact same resistance value ($1000\ \Omega$ is standard).

2. Running Time: Ensure the $14\text{s}$ vs $29\text{s}$ running time matches. A mismatched running time can destabilize the burner's PID control loop.

3. Shaft Orientation: While the SQM10 is CW, ensure your mechanical linkage is compatible with the "Home" position.

The Siemens SQN30 series (and its counterpart, the SQN31) consists of small electromotoric actuators designed to drive gas or air dampers on small to medium-sized burners.¹ They are highly reliable and are typically controlled by burner management systems like the LGB, LME, or LMO.

1. Model Differentiation

The primary difference between the two main series is the direction of rotation:

• SQN30: Clockwise (CW) rotation (when looking at the shaft).

• SQN31: Counter-clockwise (CCW) rotation (when looking at the shaft).

2. Technical Specifications

3. Internal Features & Components

The SQN30 is a "Smart" mechanical actuator  containing a reversible synchronous motor and a specialized gear train.

• Adjustable Cams: It contains multiple cams (usually color-coded) that trigger microswitches to define:

• High-Fire (Max) Position: Usually a Red cam.

• Low-Fire (Min) Position: Usually a Blue cam.

• • Ignition/Auxiliary Positions: Usually Orange or Black cams.

• Manual Disengagement: A small lever or push-button allows the gear train to be decoupled so the shaft can be turned by hand during commissioning.

• Shaft Options: Typically features a 10 mm diameter shaft with a flat side ("D-shape") or a square shaft depending on the specific burner assembly requirement.

4. Control Wiring

The SQN30 series supports various control methods depending on the terminal configuration (versions A, B, or C):

1. 2-Stage Control: Moves between a pre-set Minimum and Maximum position based on a single-pole switch .

2. Modulating Control: When used with a PID controller (like the Siemens RWF series), the actuator can be stopped at any intermediate position to precisely match the heat demand.

5. Maintenance and Replacement

 

• Lubrication: The gear train is permanently lubricated and does not require maintenance.

• Replacement Warning: When replacing an SQN30, ensure the running time  4.5s vs 30s) matches exactly. If the running time is too slow, the burner controller may time out and go into "Air Pressure Failure" or "Sequence Error."

Energy Combustion, Ahmedabad suppliers of Siemens make burner servomotor / Siemens Actuators.

 
The Siemens SQM45...B9 version is the upgraded, modern successor to the older A9 series. While they are physically and functionally interchangeable, the "B9" version features a major internal technology upgrade.

1. The Key Difference: Hall Sensor vs. Potentiometer 

• A9 Version: Used a double conductive plastic potentiometer for position feedback. Potentiometers are mechanical and can wear out over thousands of cycles.

• B9 Version: Uses a Hall Effect sensor (magnetic) for position feedback. Since there is no physical contact, it does not wear out, leading to significantly higher reliability and a longer service life.

2. Full Specifications (SQM45...B9) 3. Model Specifics (Shaft Types)

The B9 version is available with the two standard shaft configurations:

• SQM45.291B9: Features a $10\text{ mm}$ shaft with a Woodruff key. (Replaces SQM45.291A9)

• SQM45.295B9: Features a $10\text{ mm}$ D-shaped shaft (flat side). (Replaces SQM45.295A9)

4. Installation & Compatibility

• Direct Replacement: The B9 is a "drop-in" replacement for the A9. No mechanical modifications are usually required.

• Electrical Connection: Uses the same RAST3.5 edge connectors.

• Initialization: When installed for the first time or replaced, the LMV5 system will automatically recognize the new actuator. You must perform a "Reference Run" via the AZL52 display to calibrate the zero-point.

• Construction: Pressure die-cast aluminum lower housing with a heat-resistant, impact-proof black plastic cover.

5. Why the B9 is Better

In high-cycle industrial applications, the original A9 potentiometers could eventually develop "dead spots" or signal noise. By moving to a Hall sensor, Siemens eliminated the most common failure point in these actuators, making the B9 version essential for modern low-maintenance burner management. 

The Siemens SQM series consists of high-precision, robust actuators designed for medium to large industrial burners. Unlike the compact SQN series, the SQM range is built for heavy-duty dampers and is the standard for Linkageless (LMV) or Modulating (RWF) systems.

1. SQM Series Comparison Table

The SQM series is categorized by torque and the type of control interface (Analog vs. Stepper Motor).

2. SQM10 / SQM20 Series

These are reversible electromotoric actuators used for the control of air and fuel dampers.

• Torque: Up to 10 Nm (SQM10) or 20 Nm (SQM20).

• Running Times: Adjustable via internal gearing or motor selection.

• Cams: Features adjustable cams for end and auxiliary switches.

• Shaft: Generally 10 mm or 12 mm.

3. SQM33 Series

This is a compact, high-speed actuator specifically designed to be controlled by the LMV2 or LMV3 burner management system via the CAN bus.

• Torque: 1.2 Nm to 3 Nm.

• Precision: 0.1 (Stepper motor resolution).

• No Cams: Positioning is handled entirely by the LMV electronic "brain"; there are no manual cams to adjust.

• IP Rating: IP54 as standard.

4. SQM40 / SQM41 Series

Used as a mid-range actuator for LMV systems or as a standalone unit for modulating burners.

• Torque: 5 Nm (SQM40) to 10 Nm (SQM41).

• Control: Available with CAN bus (for LMV) or 4-20 mA / 0-10 V (for PLC control).

5. SQM50 / SQM53 / SQM56 Series

• Torque: Up to 40 Nm.

• Running Times: 10-60 seconds.

• Versatility: Can be fitted with internal potentiometers (1000\ \Omega) for position feedback.

• Mounting: Large flange mounting with heavy-duty drive shafts (up to 14 mm).

6. SQM50/53/56 Specifications

The Siemens SQM48...B9 series represents the latest generation of heavy-duty stepper motor actuators designed specifically for the LMV5 Burner Management System. The "B9" designation indicates a significant technology shift from mechanical potentiometers to non-contacting Hall Effect sensors, which eliminates mechanical wear and ensures lifelong positioning accuracy.

1. Technical Specifications (B9 Series) 2. All Models in the SQM48 B9 

The SQM48 series is primarily divided by torque capacity and shaft configuration. Note that all B9 models are direct, "drop-in" replacements for their older A9 counterparts.

Selection Tip: The SQM48.497B9 is the most common model for heavy air dampers, while the SQM48.697B9 is utilized for the largest industrial butterfly valves requiring maximum holding force.

3. Improvements: B9 vs. A9

• Lifespan: Because the Hall sensor does not rely on a physical wiper moving across a plastic track (as the A9 potentiometer did), it does not develop "dead spots" over millions of cycles.

• Signal Stability: Magnetic sensing is less susceptible to the electrical noise or dust interference that could occasionally plague mechanical potentiometers.

• Reliability: The B9 series drastically reduces "Positioning Faults" in high-modulation burners where the actuator is constantly moving.

4. Operational Requirements

• Reference Run: Like all LMV5 actuators, a new SQM48 B9 must undergo a "Reference Run" during commissioning. The LMV5 drives the actuator to its mechanical stop to define the absolute zero point.

• CAN Addressing: Each actuator must be assigned a unique node address (e.g., Node 1 for Fuel, Node 2 for Air) using the AZL52 display unit.

• Wiring: Requires the AGG5.641 or AGG5.631 shielded 5-core CAN bus cable to ensure safety-critical communication is not interrupted by EM interference.

5. Maintenance 

• Gears: The spur gear drive is permanently lubricated and maintenance-free.

• Manual Overriding: Never attempt to rotate the shaft manually while the actuator is powered. Unlike the SQN series, there is no manual clutch. Any forced movement can damage the internal stepper motor logic or gears.

The Siemens SQM48...B9 series represents the latest generation of heavy-duty stepper motor actuators designed specifically for the LMV5 Burner Management System. The "B9" designation indicates a significant technology shift from mechanical potentiometers to non-contacting Hall Effect sensors, which eliminates mechanical wear and ensures lifelong positioning accuracy.

1. Technical Specifications (B9 Series)

2. All Models in the SQM48 B9 The SQM48 series is primarily divided by torque capacity and shaft configuration. Note that all B9 models are direct, "drop-in" replacements for their older A9 counterparts.

Selection Tip: The SQM48.497B9 is the most common model for heavy air dampers, while the SQM48.697B9 is utilized for the largest industrial butterfly valves requiring maximum holding force.

3. Improvements: B9 vs. A9

• Lifespan: Because the Hall sensor does not rely on a physical wiper moving across a plastic track (as the A9 potentiometer did), it does not develop "dead spots" over millions of cycles.

• Signal Stability: Magnetic sensing is less susceptible to the electrical noise or dust interference that could occasionally plague mechanical potentiometers.

• Reliability: The B9 series drastically reduces "Positioning Faults" in high-modulation burners where the actuator is constantly moving.

4. Operational Requirements

• Reference Run: Like all LMV5 actuators, a new SQM48 B9 must undergo a "Reference Run" during commissioning. The LMV5 drives the actuator to its mechanical stop to define the absolute zero point.

• CAN Addressing: Each actuator must be assigned a unique node address (e.g., Node 1 for Fuel, Node 2 for Air) using the AZL52 display unit.

• Wiring: Requiresthe AGG5.641 or AGG5.631 shielded 5-core CAN bus cable to ensure safety-critical communication is not interrupted by EM interference.

5. Maintenance 

• Gears: The spur gear drive is permanently lubricated and maintenance-free.

• Manual Overriding: Never attempt to rotate the shaft manually while the actuator is powered. Unlike the SQN series, there is no manual clutch. Any forced movement can damage the internal stepper motor logic or gears. 

Energy Combustion, Ahmedabad importer and suppliers of Siemens make burner servomotor and other accessories for industrial applications.

The Siemens SQN90 is a series of compact, reversible electromotoric actuators used for the control of air and gas dampers on small to medium-sized burners. They are often used in conjunction with burner controllers like the LMO, LME, or LGB.

1. Primary SQN90 Models

The specific model suffix determines the direction of rotation, torque, and running time.

2. Technical Specifications

• Mains Voltage: $230\text{V AC}$ ($+10\% / -15\%$) or $115\text{V AC}$ variants.

• Frequency: $50\dots 60\text{ Hz}$.

• Power Consumption: Approx. $8\text{ VA}$.

• Angular Adjustment: Max $160\text{°}$ (standard factory set to $90\text{°}$).

• Protection Class: IP40 (when mounted correctly).

• Operating Temp: $-20\text{°C}$ to $+60\text{°C}$.

• Mounting Position: Optional (can be mounted horizontally or vertically).

• Shaft Type: $8\text{ mm}$ square shaft or "D" shaped shaft (depending on the version).

3. Internal Components & Adjustments

The SQN90 contains a set of adjustable cams that control the travel limits and auxiliary switches:

1. End Switches: Two switches (red and blue cams) define the Maximum Open and Minimum/Closed positions.

2. Auxiliary Switches: Up to three additional switches (black or grey cams) can be used to signal the burner controller when the damper has reached a specific intermediate position (e.g., "Ignition Position").

3. Manual Release: Most models feature a push-button or lever to disengage the gears, allowing the shaft to be turned by hand for setup and commissioning.

4. Key Features

• Reversible Motor: Unlike some older actuators, the SQN90 can move in both directions, allowing for precise modulating control when paired with a PID controller.

• Internal Potentiometer (Optional): Some versions can be fitted with a $1000\ \Omega$ or $5000\ \Omega$ potentiometer to provide feedback on the actual position to a remote display or PLC.

5. Wiring Overview

The actuator typically connects via a plug-in screw terminal block.

• Terminals 1 & 2: Usually the "Open" and "Close" control signals from the burner controller.

• Auxiliary Terminals: Used to "prove" to the burner controller that the air damper is fully open during the pre-purge phase.

Note: When replacing an SQN90, always check the direction of rotation (SQN90 = Clockwise, SQN91 = Counter-clockwise) as installing the wrong one can cause the burner to fail its pre-ignition safety checks.  

The Siemens SQN31 series is the counter-clockwise (CCW) rotating counterpart to the SQN30. These actuators are electromotoric, reversible units used to control air or gas dampers on small to medium-sized burners.

1. SQN31 Model Overview

The model number determines the running time, torque, and the internal circuit configuration (versions A, B, or C).

2. Technical Specifications 3. Internal Components 

The SQN31 uses a synchronous motor and a gear train that can be manually disengaged.

The Cam System

The actuator is controlled by several color-coded adjustable cams that trigger microswitches:

• Red Cam: High-fire / Maximum position.

• Blue Cam: Low-fire / Fully closed position.

• Orange/Black/Pink Cams: Auxiliary switches used for ignition position or to trigger external components (like a second fuel valve).

Manual Release

A small lever on the housing allows you to decouple the motor from the gear train. This is essential during installation to manually check if the damper moves freely without binding.

4. Wiring & Control Versions

The SQN31 is available in different "Internal Circuit" versions which dictate how it communicates with the burner controller:

• Version A: Standard 2-position control.

• Version B: Primarily for burners with air damper control through the burner controller (e.g., LME22).

• Version C: Often used for modulating control where an external controller (like an RWF55) provides "Open" and "Close" pulses.

5. Comparison: SQN30 vs SQN31

It is critical to choose the correct model based on your burner’s mechanical linkage:

• SQN30: Rotates Clockwise to open the damper.

• SQN31: Rotates Counter-clockwise to open the damper.

The Siemens SQN31 series is the counter-clockwise (CCW) rotating counterpart to the SQN30. These actuators are electromotoric, reversible units used to control air or gas dampers on small to medium-sized burners.

1. SQN31 Model Overview

The model number determines the running time, torque, and the internal circuit configuration (versions A, B, or C).

2. Technical Specifications 3. Internal Components 

The SQN31 uses a synchronous motor and a gear train that can be manually disengaged.

The Cam System

The actuator is controlled by several color-coded adjustable cams that trigger microswitches:

• Red Cam: High-fire / Maximum position.

• Blue Cam: Low-fire / Fully closed position.

• Orange/Black/Pink Cams: Auxiliary switches used for ignition position or to trigger external components (like a second fuel valve).

Manual Release

A small lever on the housing allows you to decouple the motor from the gear train. This is essential during installation to manually check if the damper moves freely without binding.

4. Wiring & Control Versions

The SQN31 is available in different "Internal Circuit" versions which dictate how it communicates with the burner controller:

• Version A: Standard 2-position control.

• Version B: Primarily for burners with air damper control through the burner controller (e.g., LME22).

• Version C: Often used for modulating control where an external controller (like an RWF55) provides "Open" and "Close" pulses.

5. Comparison: SQN30 vs SQN31

It is critical to choose the correct model based on your burner’s mechanical linkage:

• SQN30: Rotates Clockwise to open the damper.

• SQN31: Rotates Counter-clockwise to open the damper.

Energy Combustion, Ahmedabad importer and suppliers of Siemens make burner servomotor and other accessories for industrial applications.

The Siemens SQN90 is a series of compact, reversible electromotoric actuators used for the control of air and gas dampers on small to medium-sized burners. They are often used in conjunction with burner controllers like the LMO, LME, or LGB.

1. Primary SQN90 Models

The specific model suffix determines the direction of rotation, torque, and running time.

2. Technical Specifications

• Mains Voltage: $230\text{V AC}$ ($+10\% / -15\%$) or $115\text{V AC}$ variants.

• Frequency: $50\dots 60\text{ Hz}$.

• Power Consumption: Approx. $8\text{ VA}$.

• Angular Adjustment: Max $160\text{°}$ (standard factory set to $90\text{°}$).

• Protection Class: IP40 (when mounted correctly).

• Operating Temp: $-20\text{°C}$ to $+60\text{°C}$.

• Mounting Position: Optional (can be mounted horizontally or vertically).

• Shaft Type: $8\text{ mm}$ square shaft or "D" shaped shaft (depending on the version).

3. Internal Components & Adjustments

The SQN90 contains a set of adjustable cams that control the travel limits and auxiliary switches:

1. End Switches: Two switches (red and blue cams) define the Maximum Open and Minimum/Closed positions.

2. Auxiliary Switches: Up to three additional switches (black or grey cams) can be used to signal the burner controller when the damper has reached a specific intermediate position (e.g., "Ignition Position").

3. Manual Release: Most models feature a push-button or lever to disengage the gears, allowing the shaft to be turned by hand for setup and commissioning.

4. Key Features

• Reversible Motor: Unlike some older actuators, the SQN90 can move in both directions, allowing for precise modulating control when paired with a PID controller.

• Internal Potentiometer (Optional): Some versions can be fitted with a $1000\ \Omega$ or $5000\ \Omega$ potentiometer to provide feedback on the actual position to a remote display or PLC.

5. Wiring Overview

The actuator typically connects via a plug-in screw terminal block.

• Terminals 1 & 2: Usually the "Open" and "Close" control signals from the burner controller.

• Auxiliary Terminals: Used to "prove" to the burner controller that the air damper is fully open during the pre-purge phase.

Note: When replacing an SQN90, always check the direction of rotation (SQN90 = Clockwise, SQN91 = Counter-clockwise) as installing the wrong one can cause the burner to fail its pre-ignition safety checks.  

The Siemens SQN30 series (and its counterpart, the SQN31) consists of small electromotoric actuators designed to drive gas or air dampers on small to medium-sized burners.¹ They are highly reliable and are typically controlled by burner management systems like the LGB, LME, or LMO.

1. Model Differentiation

The primary difference between the two main series is the direction of rotation:

• SQN30: Clockwise (CW) rotation (when looking at the shaft).

• SQN31: Counter-clockwise (CCW) rotation (when looking at the shaft).

Popular Models 2. Technical Specifications 3. Internal Features & Components

The SQN30 is a "Smart" mechanical actuator  containing a reversible synchronous motor and a specialized gear train.

• Adjustable Cams: It contains multiple cams (usually color-coded) that trigger microswitches to define:

• High-Fire (Max) Position: Usually a Red cam.

• Low-Fire (Min) Position: Usually a Blue cam.

• • Ignition/Auxiliary Positions: Usually Orange or Black cams.

• Manual Disengagement: A small lever or push-button allows the gear train to be decoupled so the shaft can be turned by hand during commissioning.

• Shaft Options: Typically features a 10 mm diameter shaft with a flat side ("D-shape") or a square shaft depending on the specific burner assembly requirement.

4. Control Logic & Wiring

The SQN30 series supports various control methods depending on the terminal configuration (versions A, B, or C):

1. 2-Stage Control: Moves between a pre-set Minimum and Maximum position based on a single-pole switch .

2. Modulating Control: When used with a PID controller (like the Siemens RWF series), the actuator can be stopped at any intermediate position to precisely match the heat demand.

5. Maintenance and Replacement

• Lubrication: The gear train is permanently lubricated and does not require maintenance.

• Replacement Warning: When replacing an SQN30, ensure the running time (e.g., 4.5s vs 30s) matches exactly. If the running time is too slow, the burner controller may time out and go into "Air Pressure Failure" or "Sequence Error."  

Energy Combustion, Ahmedabad suppliers of Siemens make burner servomotor / Siemens Actuators.
 
The Siemens SQM45...B9 version is the upgraded, modern successor to the older A9 series. While they are physically and functionally interchangeable, the "B9" version features a major internal technology upgrade.

1. The Key Difference: Hall Sensor vs. Potentiometer 

• A9 Version: Used a double conductive plastic potentiometer for position feedback. Potentiometers are mechanical and can wear out over thousands of cycles.

• B9 Version: Uses a Hall Effect sensor (magnetic) for position feedback. Since there is no physical contact, it does not wear out, leading to significantly higher reliability and a longer service life.

2. Full Specifications (SQM45...B9) 3. Model Specifics (Shaft Types)

The B9 version is available with the two standard shaft configurations:

• SQM45.291B9: Features a $10\text{ mm}$ shaft with a Woodruff key. (Replaces SQM45.291A9)

• SQM45.295B9: Features a $10\text{ mm}$ D-shaped shaft (flat side). (Replaces SQM45.295A9)

4. Installation & Compatibility

• Direct Replacement: The B9 is a "drop-in" replacement for the A9. No mechanical modifications are usually required.

• Electrical Connection: Uses the same RAST3.5 edge connectors.

• Initialization: When installed for the first time or replaced, the LMV5 system will automatically recognize the new actuator. You must perform a "Reference Run" via the AZL52 display to calibrate the zero-point.

• Construction: Pressure die-cast aluminum lower housing with a heat-resistant, impact-proof black plastic cover.

5. Why the B9 is Better

In high-cycle industrial applications, the original A9 potentiometers could eventually develop "dead spots" or signal noise. By moving to a Hall sensor, Siemens eliminated the most common failure point in these actuators, making the B9 version essential for modern low-maintenance burner management.  

The Siemens SQM10 series is an electromotoric actuator designed for the precise control of gas and air dampers on medium to large burners. Unlike the compact SQN series, the SQM10 features a robust die-cast aluminum housing and high-torque gears, making it suitable for heavy-duty industrial environments.

1. SQM10 Model Variants

The model number specifies the running time, torque, and the internal circuit configuration. The SQM10 is a clockwise (CW) rotating unit.

Note: Suffixes like .15562 usually include a built-in potentiometer for position feedback ($1000\ \Omega$).

2. Technical Specifications 3. Internal Components & Adjustments

The SQM10 is powered by a reversible synchronous motor and uses a traditional cam-and-switch system for positioning.

• Cams: The unit contains multiple adjustable cams (Red, Blue, Orange, etc.) that define the travel limits and ignition points.

• Potentiometer (Optional): Many SQM10 units are fitted with a conductive plastic potentiometer to provide a $4\dots 20\text{ mA}$ or $0\dots 10\text{ V}$ feedback signal to an external controller (like the Siemens RWF55).

• Manual Release: There is a manual decoupling lever that allows you to rotate the shaft by hand for mechanical alignment during installation.

4. Key Applications

The SQM10 is the preferred choice for:

• Modulating Burners: Where the air damper must constantly adjust to maintain the correct oxygen levels.

• Large Air Dampers: Where the torque required exceeds the capability of the plastic SQN series.

• Industrial Kilns and Ovens: Where durability and high IP ratings are required.

5. Selection and Replacement

If you are replacing an SQM10, you must check the Suffix:

1. Potentiometer: If your existing unit has a potentiometer (used for feedback), the new one must have the exact same resistance value ($1000\ \Omega$ is standard).

2. Running Time: Ensure the $14\text{s}$ vs $29\text{s}$ running time matches. A mismatched running time can destabilize the burner's PID control loop.

3. Shaft Orientation: While the SQM10 is CW, ensure your mechanical linkage is compatible with the "Home" position.

Siemens burner servomotors (actuators) are the industry standard for controlling the air-to-fuel ratio in combustion systems. They are categorized into two main technologies: Electromechanical (SQN) for traditional linkage-based burners and Electronic/Stepper (SQM) for modern linkageless (LMV) systems.

1. SQN Series (Electromechanical)

The SQN series uses reversible synchronous motors with adjustable mechanical cams.¹ They are used with controllers like the LME, LMO, or LGB.²

+1

 

Details:

• Adjustment: Uses color-coded cams (Red: Max, Blue: Min, Orange: Ignition).

• Manual Release: Features a clutch to disengage gears for manual commissioning.

• Protection: Typically IP40.

2. SQM Series (Electronic & Stepper)

The SQM series is more robust, offering higher torque and precision. They are divided into "Analog" (cams/potentiometers) and "Digital" (CAN bus stepper).

A. Analog/Modulating Models (SQM10, 20, 50)

Used for standalone modulating control (e.g., with RWF55) or traditional linkages.

• SQM10/20: Up to $20$ Nm torque. Aluminum housing.

• SQM50/53/56: The industrial workhorses. Torque up to $40$ Nm. $100\%$ duty cycle.

B. Linkageless Stepper Models (SQM33, 45, 48, 91)

Specifically for LMV2/3 and LMV5 systems. No mechanical cams; positioning is handled via CAN bus.

3. Technical Comparison: SQN vs. SQM 4. Key Selection Factors

When choosing or replacing a Siemens servomotor, you must verify:

1. Direction of Rotation: Clockwise (e.g., SQN30) vs. Counter-clockwise (e.g., SQN31).

2. Running Time: $90^\circ$ travel must match the burner controller's sequence (e.g., $12$s vs $30$s).

3. Shaft Type: Square, D-shape, or Woodruff key.

4. Interface: 3-position relay (SQN) vs. CAN bus (SQM33/45/48) vs. $4-20$ mA (SQM40/41). 

The Siemens SQN70 (and its counterpart SQN71) is a range of electromotoric actuators designed to drive gas or air dampers on small to medium-sized burners.¹ They are often referred to as "high-torque" compact actuators compared to the SQN30 series and are typically used with burner controllers like the LME, LMO, or LGB.

 

1. SQN70 vs. SQN71: Direction of Rotation

• SQN70: Rotates Clockwise (CW) when looking at the drive shaft.

• SQN71: Rotates Counter-clockwise (CCW) when looking at the drive shaft.

2. All Models & Running Times

The model number determines the internal circuit (Version A, B, C, or D), the running time, and the torque.

Versions/Circuits

• Version A: For 2-stage control (High/Low) with no internal electronic ratio control.

• Version B: Primarily for use with controllers like the LME22.

• Version C: Designed for modulating control via a 3-position signal (Open/Stop/Close).

• Version D: Typically used with the LFL series or for specific industrial sequences.

3. Technical Specifications 4. Internal Components

The SQN70 series features a reversible synchronous motor and a gear train that can be manually disengaged for adjustment.²

 

The Cam Logic

Inside the housing are several color-coded cams that trigger microswitches to define the operational limits:

• Red Cam: Maximum position (High-fire).

• Blue Cam: Minimum position (Closed or Low-fire).

• Orange/Black Cams: Auxiliary switches for "Ignition load" or "Release of fuel."

5. Key Features

• Maintenance-Free: The gear train is permanently lubricated.

• Manual Release: A push-button or lever on the housing allows the gears to be decoupled. This is vital for checking the mechanical linkage for binding without the motor running.

• Potentiometer Option: Some SQN70 models can be retrofitted with a $1,000\ \Omega$ potentiometer for position feedback to a PLC or display unit.

6. Maintenance and Selection Tip

1. Direction: (70 vs 71).

2. Running Time: (e.g., $2$s vs $30$s). If you install a slower actuator, the burner controller might go into lockout during the pre-purge transition.

3. Circuit Version: (e.g., A vs B). Using the wrong circuit version will result in the actuator not moving even when powered. 

The Siemens SQN75 series consists of reversible electromotoric actuators specifically designed for the control of gas and air dampers on burners of small to medium capacity. They are distinguished from the SQN70/71 models by their completely black housing (both the gear train and the cover) and are often used as direct replacements for older Conectron or Berger actuators.

1. Key Performance Specifications 2. All SQN75 Models & Specifics

The SQN75 series uses a modular "Circuit Diagram" numbering system. The middle digits (e.g., .294 or .424) define the running time, torque, and internal relay/switch count.

3. Design & Features

• Housing: Made of impact-proof and heat-resistant plastic. The black color indicates it is part of the SQN74/SQN75 branch of the family.

• Motor: Reversible and locking-proof synchronous motor.

• Geartrain: Maintenance-free with a manual disengagement mechanism (Pin K). Pressing this allows the shaft to be rotated by hand for commissioning.

• Adjustment: Switching points are set via color-coded adjustable cams. Some models include fine-adjustment screws that can be turned with a standard screwdriver.

• Potentiometer: Special versions are "ready-prepared" for fitting a potentiometer for position feedback ($1000\ \Omega$ or $5000\ \Omega$).

4. Selection Tip: SQN74 vs SQN75

While both are black-housed actuators:

• SQN74: Rotates Counter-clockwise (CCW).

• SQN75: Rotates Clockwise (CW).

  Installing the wrong rotation direction will cause the burner to fail its pre-ignition safety check.