Carrier 50TFQ008-012 EconoMi$er IV Input/Output Logic, Demand Control Enthalpy, Terminal†

Table 29 — EconoMi$er IV Input/Output Logic

	INPUTS						OUTPUTS
Demand Control	Enthalpy*				Compressor		N Terminal†
			Y1	Y2	Stage	Stage	Occupied	Unoccupied
Ventilation (DCV)	Outdoor	Return
					1	2	Damper
Below set	High	Low	On	On	On	On	Minimum position	Closed
(DCV LED Off)	(Free Cooling LED Off)		On	Off	On	Off
			Off	Off	Off	Off
	Low	High	On	On	On	Off	Modulating** (between min.	Modulating** (between
	(Free Cooling LED On)		On	Off	Off	Off	position and full-open)	closed and full-open)
			Off	Off	Off	Off	Minimum position	Closed
Above set	High	Low	On	On	On	On	Modulating†† (between min.	Modulating†† (between
(DCV LED On)	(Free Cooling LED Off)		On	Off	On	Off	position and DCV maximum)	closed and DCV
								maximum)
			Off	Off	Off	Off
	Low	High	On	On	On	Off	Modulating***	Modulating†††
	(Free Cooling LED On)		On	Off	Off	Off
			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), no power (Unoccupied).

**Modulation 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 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 supply-air sen- sor signals, between closed and either maximum position (DCV) or fully open (supply-air signal).

Fig. 51 — EconoMi$er IV Functional View

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