SM-15/37 Servo Motor Actuator Model SM-15/37

Transcription

1 SM-15/37 Servo Motor Actuator Model SM-15/37 Operation Manual SDI-SM-15/37 Revision 2 10/26/2009 Servo Motor Actuator Precision Potentiometer Aluminum Casing Internal Brake for Positive Positioning Optional Limit Switch for up to 2 Aux Switches Optional Shaft Ends Optional Foot Mount Mounting Bracket CONTENTS Description 2 Installation 3 Options 4 INTRODUCTION This manual is intended to describe the installation and operation of a SM-15/37 Servo Motor Actuator. This manual is intended to be used by operators, plant engineers and service engineers. Specifications 5 SM-15 actuator shown with 2 limit switches and M1 mounting bracket Preferred Instruments Danbury, CT USA

2 DESCRIPTION OVERVIEW DESCRIPTION The model SM-15/37 Servo Motor Actuator provides directly connected and precise modulating control of fuel valves ad combustion air and flue gas control dampers. The actuator opens, modulates, and closes the valves and/ or dampers in accordance with the integrated combustion control and burner management system programs. The feedback potentiometer provides indication of the motor's shaft position. The SM actuators are used on boiler applications that have a maximum of 37 ft-lbs torque required. The SM-15/37 actuator utilizes an instantly reversible motor to rotate a hardened steel output shaft through a reduction of precision hobbed gears. The output shaft actuates two adjustable cam operated travel limit switches to stop motor operation at pre-selected positions. The output shaft can be extended via the optional limit switch assembly to include two auxiliary switches to provide valve and damper position proving interlocks. OPTIONS SHAFT EXTENSIONS Three shaft extensions are available for the SM-15 and SM-37 Servo Motor Actuators. Two extensions allow for mounting of two auxiliary limit switches. Each comes with a different shaft end. One is a square shaft, the other is round. The third shaft extension is used to convert the round shaft to a square shaft without the use of auxiliary limit switches. See Options section of this manual for more information. LIMIT SWITCHES The auxiliary limit switch kit allows for up to two position switches to be installed. These switches are commonly used for proof of position interlocks. The motor has an integral brake for positive positioning, and can be stopped, started, or instantly reversed at any time within it's travel without overheating or loss of power. FIELD ADJUSTMENT FOR LIMIT SWITCHES The SM Actuator comes with pre-set limit switches from the factory. However, it can become necessary to adjust these switches if the position of the actuator shaft is not aligned properly with the actuator shaft. Cam setting adjustment for fully-closed position: 1. Drive actuator shaft counter-clockwise until it actuates the limit switches (fully-closed position) 2. Drive the valve to a fully-closed position manually If actuator shaft is turned pass the valve shaft: 3. Drive actuator shaft clockwise until it is perfectly aligned with the valve shaft 4. Set CCW limit switch cam for this position by rotating the cam counter-clockwise until you hear a "CLICK" from the limit switch 5. Adjust as necessary if actuator shaft does not turn enough to align valve shaft: 3. Rotate the CCW limit switch cam clockwise to give the limit switch more travel range 4. Drive actuator counter-clockwise until its shaft is perfectly aligned with the valve shaft 5. Set CCW limit switch cam for this position by rotating the cam counter-clockwise until you hear a "CLICK" from the limit switch 6. Adjust as necessary Cam setting adjustment for fully open position: 1. Drive actuator shaft clockwise until it actuates the limit switches (fully-open position) 2. Drive the valve to a fully-open position manually If actuator shaft is turned pass the valve shaft: 3. Drive actuator counter-clockwise until its shaft is perfectly aligned with the valve shaft 4. Set CW limit switch cam for this position by rotating the cam clockwise until you hear a "CLICK" from the limit switch 5. Adjust as necessary if actuator shaft does not turn enough to align valve shaft: 3. Rotate the CW limit switch cam counter-clockwise to give the limit switch more travel range 4. Drive actuator clockwise until its shaft is perfectly aligned with the valve shaft 5. Set CW limit switch cam for this position by rotating the cam clockwise until you hear a "CLICK" from the limit switch 6. Adjust as necessary 2

3 INSTALLATION WIRING The wiring for the SM-15/37 actuators consists of 120Vac drive voltage and a low voltage feedback potentiometer. CCW Travel Stop Switch Terminal Description Number 1 Earth Ground 1 Neutral 2 Open (120Vac) 3 Close (120Vac) 4 Close / Lamp 5 CCW 6 Wiper 7 CW CW Travel Stop Switch Feedback Pot The optional auxiliary switch kits can be wired as a normally open or normally closed switch. Terminal Number Description Normally open connection Normally closed connection 3

4 OPTIONS SHAFT EXTENSIONS The following shaft extensions are available as options for the SM-15/37 model actuator. AUXILIARY LIMIT SWITCHES (-S1, -S2 OPTION) The auxiliary limit switch kit allows two switches to be mounted to the actuator housing offering position switch feedback to the controller. Round Shaft Extension for limit switch kit (-E2 option) Square Shaft converter (PN 26174) The limit switch assembly uses cams mounted on the shaft extension to toggle the switch at adjustable positions. MOUNTING BRACKET (-M1 OPTION) A foot mount mounting bracket, as shown below, is supplied to allow proper mounting of the actuator for use as a DM-1E retrofit. For more information about DM-1E retrofits, feel free to contact your factory representative. 4

5 MODEL NUMBER LIST SPECIFICATIONS MODEL NUMBER SM K-E2-S1-M1 DESCRIPTION Servo Motor Actuator Mounting Bracket -M1 = Foot mount (for DM-1E replacement) Number of Auxiliary Switches -S1, -S2 = One or two auxiliary switches Shaft Extension Type E2 = Round with one flat 30 second stroke, 120 volt, 5K feedback Potentiometer Torque Rating -15 = 15 footpounds -37 = 37 foot-lbs Model Number Torque Shaft type Aux switches SM K-E2-S1-M1 15 Round 1 SM K-E2-S1-M1 37 Round 1 SM K-E2-S2-M1 15 Round 2 SM K-E2-S2-M1 37 Round 2 5

6 NOTES: 6

7 REVISION HISTORY Rev Description 0 First Revision 1 Unreleased 2 Edit for extended details 7

8 PI Preferred Instruments Preferred Instruments A Division of Preferred Utilities Mfg. Corp South St. Danbury, CT Phone: (203) Fax: (203) info@preferred-mfg.com