Honeywell W7340 사용자 설명서

63-2569—04 4

To measure enthalpy, the logic module accepts signals from 

either:

— C7600C Humidity and 10K NTC temperature sensors.

— or a C7400 Enthalpy Sensor.

1. Mount each sensor in any orientation that exposes it to 

freely circulating air and protects it from rain, snow, and 

direct sunlight.

2. Connect it to the logic module.

1. For differential enthalpy or temperature control mount a 

second sensor in the return air duct.

2. Connect it to the logic module.

The DCV sensor can be any sensor that provides a 0-10 Vdc 

output over a range of 0 to 2000 ppm of CO

2

. The DCV signal 

modulates the outdoor damper to provide ventilation based on 

occupancy. Mount the sensor according to the manufacturer 

specifications. If not available, mount the sensor in an area 

with unobstructed air circulation.

W7340B: The W7340B DCV economizer logic modules 

incorporate a minimum position setting that defaults to 20%, 

but can be overridden using the Modbus communication link.

The W7340B DCV maximum position sets the damper position 

to a position that the damper goes to if the CO

2

 sensor fails. If 

the minimum position set point is higher than the DCV 

maximum position, on sensor failure, the damper goes to the 

higher of the two DCV maximum and minimum position setting. 

There is no limit on the damper position on a call from the CO

2

 

sensor (DCV); the damper can go 100% open.

W7340C: The W7340C DCV economizer logic module has the 

ability to set DCV minimum damper position and minimum 

position. The DCV minimum position is set to ventilate the 

building contaminants and the minimum position is set to 

ventilate for the building contaminants and the building 

occupants. The installer sets the damper DCV minimum 

position and the minimum position based on the design 

occupancy and CFM of outdoor air requirements for the space. 

The damper will modulate open between the DCV minimum 

damper position and the minimum position based on input 

from a CO

2

 sensor. The damper will not drive 100% open on a 

call for ventilation, but can drive 100% open on a call for 

cooling. If the CO

2

 sensor fails the damper will drive to the 

minimum position ventilating for building contaminants and 

the building occupants. If the DCV minimum position has not 

been set using the following procedure, the default setting will 

be 50% of the minimum position setting.

Set up instructions for W7340C DCV damper positions:

1. Remove RAT sensor from RAT terminals.

2. Connect CO

2

 sensor to DCV terminals.

3. Apply power to economizer logic module.

4. Wait 10 to 15 seconds for the CO2 sensor to initialize. 

Short RAT terminals.

5. Remove CO

2

 sensor from DCV terminals.

6. DCV LED will blink 2 times. If LED does not blink, cut 

power to economizer logic and repeat steps 1-5.

7. Set DCV minimum position using MIN POS/DCV MIN 

potentiometer.

8. Remove RAT short.

9. DCV minimum position is saved to memory and DCV 

LED blinks 5 times.

10. Turn off power to economizer logic module.

11. Connect RAT sensor.

12. Turn power on to economizer logic module.

13. Set minimum position using MIN POS/DCV MIN 

potentiometer.

M17638