Carrier 50TFQ004 Installation, Start-Up And Service Instructions Manual page 51

INPUTS
Demand Control
Ventilation (DCV)
Below set High
(DCV LED Off) (Free Cooling LED Off)
Low
(Free Cooling LED On)
Above set High
(DCV LED On) (Free Cooling LED Off)
Low
(Free Cooling LED On)
*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), no power (Unoccupied).
**Modulation is based on the supply-air sensor signal.
††Modulation is based on the DCV signal.
Table 34 — EconoMi$er IV Input/Output Logic
Enthalpy*
Y1
Outdoor Return
Low On On
On Off
Off Off
High On On
On Off
Off Off
Low On On
On Off
Off Off
High On On
On Off
Off Off
Fig. 53 — EconoMi$er IV Functional View
Compressor
Y2 Occupied
Stage Stage
1 2
On On Minimum position
On Off
Off Off
On Off Modulating** (between min.
position and full-open)
Off Off
Off Off Minimum position
On On Modulating†† (between min.
position and DCV maximum)
On Off
Off Off
On Off Modulating***
Off Off
Off Off
***Modulation is based on the greater of DCV and supply-air sen-
sor signals, between minimum position and either maximum
position (DCV) or fully open (supply-air signal).
†††Modulation is based on the greater of DCV and mixed air sensor
signals, between closed and either maximum position (DCV) or
fully open (supply-air signal).
51
OUTPUTS
N Terminal†
Unoccupied
Damper
Closed
Modulating** (between
closed and full-open)
Closed
Modulating†† (between
closed and DCV
maximum)
Modulating†††