Table 16 – CO2 Sensor Standard Settings

 

 

 

VENTILATION

 

CO2

OPTIONAL

RELAY

SETTING

EQUIPMENT

OUTPUT

RATE

ANALOG

CONTROL

RELAY

HYSTERESIS

(CFM/

OUTPUT

RANGE

SETPOINT

 

 

 

(PPM)

 

 

 

PERSON)

 

(PPM)

(PPM)

 

 

 

 

 

 

 

 

 

 

 

 

 

1

 

Proportional

Any

0---10V

0---2000

1000

50

 

4---20mA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2

Interface w/Standard Building

Proportional

Any

2---10V

0---2000

1000

50

Control System

7---20mA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3

 

Exponential

Any

0---10V

0---2000

1100

50

 

4---20mA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4

 

Proportional

15

0---10V

0---1100

1100

50

 

4---20mA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5

Economizer

Proportional

20

0---10V

0---900

900

50

4---20mA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

6

 

Exponential

15

0---10V

1---1100

1100

50

 

4---20mA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

7

 

Exponential

20

0---10V

0---900

900

50

 

4---20mA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

8

Health & Safety

Proportional

---

0---10V

0---9999

5000

500

4---20mA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

9

Parking/Air Intakes/Loading Docks

Proportional

---

0---10V

0---2000

700

50

4---20mA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 17 – CO2 Sensor Standard Settings Economizer Input/Output Logic

 

INPUTS

 

 

 

 

 

OUTPUTS

 

 

 

 

 

 

 

 

 

 

DEMAND

ENTHALPY

 

 

 

COMPRESSOR

N TERMINAL

CONTROL

 

 

 

 

 

 

 

 

 

 

Y1

Y2

STAGE

STAGE

OCCUPIED

UNOCCUPIED

VENTILATION

OUTDOOR

RETURN

 

 

 

 

(DCV)

 

 

 

 

1

2

DAMPER

 

 

 

 

 

 

 

 

 

 

High (Free Cooling

 

On

On

On

On

 

 

 

 

 

 

 

 

 

 

 

Low

On

Off

On

Off

Minimum position

Closed

 

LED off)

 

 

 

 

 

 

 

 

Below set (DCV

 

 

Off

Off

Off

Off

 

 

LED Off)

 

 

 

 

 

 

 

 

Low (Free Cooling

 

On

On

On

Off

Modulating** (between min.

Modulating** (between closed

 

High

On

Off

Off

Off

position and full ---open)

and full ---open)

 

LED on)

 

 

 

 

 

 

 

 

 

 

Off

Off

Off

Off

Minimum position

Closed

 

 

 

 

 

 

 

 

 

 

High (Free Cooling

 

On

On

On

On

Modulating{{ (between

Modulating{{ (between closed

 

 

 

 

 

 

 

Low

On

Off

On

Off

min. position and DCV

 

LED off)

and DCV maximum)

 

 

 

 

 

 

maximum)

Above set (DCV

 

 

Off

Off

Off

Off

 

 

 

 

 

LED On)

 

 

 

 

 

 

 

 

Low (Free Cooling

 

On

On

On

Off

 

 

 

 

 

 

 

 

 

 

 

High

On

Off

Off

Off

Modulating***

Modulating{{{

 

LED on)

 

 

 

 

 

 

 

 

 

 

 

Off

Off

Off

Off

 

 

 

 

 

 

 

 

 

 

 

* For single enthalpy control, the module compares outdoor enthalpy to the ABCD set point.

{Power at N terminal determines Occupied/Unoccupied setting: 24 vac (Occupied), now power (Unoccupied). **Modulating is based on the supply--- air sensor signal.

{{Modulation is based on the DCV signal.

***Modulation is based on the greater of DCV and supply--- air sensor signals, between minimum position and either maximum position (DCV) or fully open (supply--- air signal).

{{{Modulating is based on the greater of DCV and supply--- air sensor signals, between closed and wither maximum position (DCV) or fully open (supply--- air signal).

607C-- -- A

OPERATION

Sequence of Operation—When free cooling is not available, the compressor will be controlled by the thermostat. When free cooling is available, the outdoor-air damper is modulated by the Economizer control to provide a 50_ to 55_F (10_ to 12.8_C) supply-air temperature into the zone. As the supply-air temperature fluctuates above 55_ (12.8_C) or below 50_F (10_C), the dampers will be modulated (open or close) to bring the supply-air temperature back within the set points. For Economizer operation, there must be a thermostat call for the fan (G). This will move the damper to its minimum position during the occupied mode.

NOTE: The DCV Max potentiometer must be closed (CCW) when not using CO2 sensor.

Above 50_F (10_C) supply-air temperature, the dampers will modulate from 100% open to the minimum open position. From 50_F to 45_F (10_ to 7.2_C) supply-air temperature, the dampers will maintain at the minimum open position. Below 45_F (7.2_C), the dampers will be completely shut. As the supply-air temperature rises, the dampers will come back open to the minimum open position once the supply-air temperature rises to 48_F (8.9_C). If

power exhaust is installed, as the outdoor-air damper opens and closes, the power exhaust fans will be energized and deenergized. If field-installed accessory CO2 sensors are connected to the Economizer control, a demand controlled ventilation strategy will begin to operate. As the CO2 level in the zone increases above the CO2 set point, the minimum position of the damper will be increased proportionally. As the CO2 level decreases because of the increase in fresh air, the outdoor-air damper will be proportionally closed. Damper position will follow the higher demand condition from DCV mode or free cooling mode. Damper movement from full closed to full open (or vice versa) will take between 1 1/2 and 2 1/2 minutes. If free cooling can be used as determined from the appropriate changeover command (dry bulb, enthalpy curve, or differential enthalpy), a call for cooling (Y1 closes at the thermostat) will cause the control to modulate the dampers open to maintain the supply air temperature set point at 50_ to 55_F (10_ to 12.8_C). As the supply air temperature drops below the set point range of 50_ to 55_F (10_ to 12.8_C), the control will modulate the outdoor-air dampers closed to maintain the proper supply-air temperature.

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Bryant 607C-A installation instructions Operation, CO2 Sensor Standard Settings Economizer Input/Output Logic