Carrier MPE62L-10R, 48MPD Ð Psychrometric Chart for, Enthalpy Control, Enthalpy Sensor HH57AC077

CONTROL	CONTROL POINT
CURVE	(Approx Deg F)
	AT 50% RH

A73

B68

C63

D58

Fig. 46 Ð Psychrometric Chart for

Enthalpy Control

NOTES:

1.Switches shown in high enthalpy state. Terminals 2 and 3 close on enthalpy decrease.

2.When standard economizer is used with accessory differential enthalpy sen- sor, set enthalpy control to ``D'' setting.

Fig. 47 Ð Wiring Connections for Solid-State

Enthalpy Sensor (HH57AC077)

KEYPAD AND DISPLAY MODULE (HSIO) CONFIGURATION

IMPORTANT: The HSIO keypad and display module is required for initial start-up of these units. All units are shipped in standby mode, and the HSIO should be used to change the unit to run mode. Once the unit is in run mode, the HSIO is not required for normal operation.

The keypad and display module provides unit function in- formation at the unit. See Fig. 48. The module consists of a keypad with 6 function keys, 5 operative keys, 10 numeric keys (0 through 9), and an alphanumeric 8-character liquid crystal display (LCD). Key usage is explained in Table 23. Each function has one or more subfunctions.

The HSIO keypad and display module is installed by con- necting the power and communication plugs and can be easily moved from one unit to another. Because of this ¯ex- ibility, one HSIO can be used for several units.

Unit operation is controlled by the status of the run/ standby mode on the HSIO. To access the mode, press

on the HSIO keypad, and then press .

The HSIO will display either STBY YES or STBY NO.

To enable the unit, press CLEAR or and press ENTER while

at the STBY YES display. To disable the unit, press

ENTER while at the STBY NO display. Clearing an alarm

that has stopped unit operation is accomplished by entering the STBY YES mode.

IMPORTANT: Use the STBY YES mode when ser- vicing the unit or running the quick test feature.

IMPORTANT: If remote start function is used, place LOCAL/REMOTE switch in Local (OFF) position when ever unit is placed in STBY YES.

SET UNIT TYPE Ð The correct unit type must be set. The default unit type is VAV. If the unit is being used in a VAV application, then the unit type does not need to be changed.

Table 23 Ð HSIO Keypad Key Usage

FUNCTION		USE
KEYS
		Status Ð To display diagnostic codes and
		current operating information about the unit.
		Quick Test Ð To check inputs and outputs for
		proper operation.
		History Ð To check most recent alarms.
		Service Ð To enter speci®c unit con®guration
		information.
		Set Point Ð To enter operating set points and
		day/time information.
		Schedule Ð To enter occupied/unoccupied
		schedules for unit operation.
OPERATIVE		USE
KEYS
		Expand Display Ð To display a non-
		abbreviated expansion of the display.
		Clear Ð To clear the screen and return to previous
	CLEAR	display. Also used to enter data value
		of zero.
		Up Arrow Ð To return to previous display position.
		Down Arrow Ð To advance to next display position.
		To enter data.
	ENTER

STAT	EXPN	1	2	3	SRVC	TEST
	EDIT					ALRM
SET	SCHD	4	5	6	HIST	ALGO
		7	8	9	CLEAR
		-	0		ENTER

Fig. 48 Ð Keypad and Display Module (HSIO)

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