R81EAA-2 Economizer Circuit Board

Transcription

1 FAN 121, Motor Actuators Section M Technical Bulletin R81E Issue Date 0993 R81EAA-2 Economizer Circuit Board Applications Setpoint Adjustment Temp T1 T2 S2 1O S Changeover Relay Refrigeration Programming Relay A C B Relay "A" Common Relay "B" B 1 B 3 X B3 B1 B2 B 2 Figure 1: R81EAA-2 Circuit Board The R81EAA-2 circuit board is a direct replacement for M110EGX, M120EGX, M130EGX, M140EGX, M150EGX, and R81EAA-2. This board only accepts the A91 thermistor sensor input and will not work with 1000 ohm nickel sensor inputs. Note: The R81EAA-3 is designed to be used with 1000 ohm nickel type inputs Johnson Controls, Inc. 1 Part No

2 Installation Procedures Tools Needed Precautions Removing Boards screwdriver, Phillips-head (No. 1 or No. 2 tip) screwdriver, flat-blade, 1/8 inch tip All Series M100 Motor Actuators are for use only as operating controls. Where an operating control failure would result in personal injury and/or loss of property, it is the responsibility of the user to add devices (safety, limit controls) or systems (alarm, supervisory systems) that protect against and/or warn of control failure. To remove the electronic circuit boards in an existing Series M100E Motor Actuator, proceed as follows.! CAUTION: To prevent possible electrical shock or damage to the equipment, disconnect the electrical power supply before attempting to remove the wiring connections and the boards. 1. Remove the motor actuator s existing top cover by loosening the two cover screws. The old cover will be replaced with the new cover furnished. 2. Verify that power is removed from the unit, tag each wire, and then remove all wiring connections to the terminal board. 3. Loosen the bracket screw and remove the bracket. 4. Pull the vertical board straight upward. Be careful not to bend or damage the pin terminals. 5. Remove the two screws from the terminal board. 6. Remove the terminal board by grasping the receptacles and lifting straight upward being careful not to bend or damage the pin terminals. 2 M R81EAA-2 Economizer Circuit Board

3 Installing Boards 1. Install the flux barrier into the wiring compartment so that all metal surfaces are covered. Terminal Board Screws Terminal Board Receptacles Flux Barrier Pin Terminals Figure 2: Terminal Receptacles 2. Install the terminal board by carefully placing the terminal receptacles onto the pin terminals as shown in Figure Fasten the board in place using the two terminal board screws removed previously. Terminal Receptacles Pin Terminals Vertical Board with Attached Cover Figure 3: Installing Vertical Board 4. Install the vertical board (with ribbon attached cover) by carefully placing the terminal receptacles onto the pin terminals as shown in Figure 3. Note: Align all pins within the receptacle. M R81EAA-2 Economizer Circuit Board 3

4 Bracket Captive Screw Figure 4: Installing Bracket 5. Place the bracket (removed in Step 3 of the Removing Boards section) over the vertical board and fasten the bracket in place with captive screw as shown in Figure Install the motor actuator. Wiring Compartment Figure 5: Wiring Junction Box Attached to M Make control and 24 VAC wiring connections.! CAUTION: To avoid possible electrical shock or damage to the equipment, disconnect the electrical power supply before wiring the motor actuator. Always disconnect the 24 VAC power supply before attempting to make any wiring connections. 8. Turn on power supply. 9. Perform travel, setpoint, proportional band, and minimum position adjustments described in the Adjustments section as required. 10. Installation is complete. 4 M R81EAA-2 Economizer Circuit Board

5 Calibration Procedures Adjustments Travel Temp T2 S2 S 1 Changeover Relay Refrigeration Programming Relay A C B Setpoint T 1 1O 8 9 X B 3 B1 B2 Adjustment Potentiometers Located on the Cover Panel Sensor Calibration Proportional Band Adjustment Minimum Position Adjustment Figure 6: Adjustment Pots Travel Setpoint The rotational travel is field adjustable from 65 to 270 degrees rotation by turning the travel adjustment located on the R81 terminal board. Changing the travel adjustment affects the CW limit of the actuator s rotation. 1. Apply 24 VAC to terminals T1 and T2. 2. Run the motor actuator to its CW limit by jumpering Terminals 8 and 9 shown in Figure Turn the adjustment potentiometer clockwise to increase the travel, and counterclockwise to decrease the travel. 4. For further information on travel adjustment, refer to the Linkage Adjustment section in the damper or valve linkage instruction sheet. An internal setpoint adjustment for the remote sensor is located on the R81 terminal board and has a calibrated dial adjustable from 40 to 90 F (5 to 30 C). When a remote setpoint is desired, turn the R81 setpoint knob counterclockwise to its limit at the low temperature end of the dial in order to adjust the setpoint from the remote location. A Y45BA-1 remote setpoint control in series with the sensor is used for remote setpoint. For room ventilation only systems, the mixed air sensor is replaced by a T91BCA room thermostat. M R81EAA-2 Economizer Circuit Board 5

6 Proportional Band The proportional band is adjustable between 2 and 20 F. (1.1 and 11 C.) Figure 7: Top Cover Adjustment Access The proportional band adjustment located on the cover mounted circuit board is accessible through the cover by removing its corresponding plug as shown in Figure 7.! CAUTION: While narrowing the proportional band is usually desirable, too narrow a proportional band may result in poor control. Increase the proportional band if the motor actuator cannot maintain a stable position when the system is operating. Instability causes the motor actuator to oscillate (hunt). 6 M R81EAA-2 Economizer Circuit Board

7 Changeover Relay A Refrigeration Relay B Minimum Position Replacement 1. Turn the outdoor air minimum position potentiometer full counterclockwise (CCW) from the board side of the cover and clockwise (CW) through the cover. 2. Energize the changeover relay by applying 24 VAC between terminals A and C. This simulates the availability of outdoor air for natural cooling. 3. Adjust the setpoint to approximately midrange, 65 F (18 C). 4. Jumper sensor terminals S1 and S2, which will simulate a rise in mixed air temperature, and the outdoor air dampers will modulate open. 5. Remove jumper and sensor between terminals S1 and S2, which now simulates a drop in mixed air temperature, and the outdoor air dampers should modulate closed. 6. Install the sensor between terminals S1 and S2. 1. Energize the refrigeration programming relay by applying 24 VAC between terminals B and C. 2. Jumper terminals B and B2. 3. Using an AC voltmeter, verify that there is 24 VAC across terminals B1 and C. 4. Remove the jumper from terminals B and B2, and remove 24 VAC from terminals B and C. 1. De-energize the changeover relay by removing power from terminals A and C. This simulates the lack of outdoor air for natural cooling and the outdoor air dampers should modulate closed. 2. By turning the minimum position potentiometer Clockwise (CW), the minimum position should increase. The motor actuator will rotate CW. 3. Restore the original connections to terminals A and C. The drive motor and gear train are immersed in oil and sealed in a die cast case. Therefore, actuator maintenance is not necessary. Make no field repairs except for replacement of R81E plug-in electronic board kits. For repair parts or replacement, contact the nearest Johnson Controls commercial systems wholesaler or Systems and Services Division branch office. M R81EAA-2 Economizer Circuit Board 7

8 Notes Controls Group 507 E. Michigan Street P.O. Box 423 Milwaukee, WI Printed in U.S.A. 8 M R81EAA-2 Economizer Circuit Board