Carrier 69NT20-531-300 manual Controller Function Codes Sheet 3

		Table 3-5 Controller Function Codes (Sheet 3 of 3)
			The stagger start offset time is the amount of time that the unit will delay at start-
Cd31	Stagger Start Offset		up, thus allowing multiple units to stagger their control initiation when all units
	Time (Seconds)		are powered up together. The eight possible offset values are:
			0 (Factory Default), 3, 6, 9, 12, 15, 18 or 21 seconds
			The current limit is the maximum current draw allowed on any phase at any time.
			Limiting the unit’s current reduces the load on the main power supply. This is
Cd32	Current Limit		accomplished by reducing the SMV position until current draw is reduced to the
	(Amperes)		set point. When desirable, the limit can be lowered. Note, however, that capacity
			is also reduced. The five values for 460vac operation are: 15, 17, 19, 21 (Factory
			Default), 23
			Relative humidity set point is available only on units configured for dehumidifi-
			cation. When the mode is activated, the control probe LED flashes on and off ev-
			ery second to alert the user. If not configured, the mode is permanently deacti-
	Perishable Mode		vated and “----------” will display. The value can be set to “OFF.” “TEST,” or a
			range of 65 to 95% relative humidity in increments of 1%. [If bulb mode is active
Cd33	Dehumidification
			(code Cd35) and “Lo” speed evaporator motors are selected (code Cd36) then set
	Control (% RH)
			point ranges from 60 to 95%.] When “TEST” is selected or test set point is
			entered, the heat LED should illuminate, indicating that dehumidification mode is
			activated. After a period of five minutes in the “TEST” mode has elapsed, the
			previously selected mode is reinstated.
Cd34	Economy Mode		Economy mode is a user selectable mode of operation provided for power saving
	(On-Off)		purposes.
			Bulb mode is a user selectable mode of operation that is an extension of dehu-
			midification control (Cd33). If dehumidification is set to “Off,” code Cd35 will
Cd35	Bulb Mode		display “Nor” and the user will be unable to change it. After a dehumidification
			set point has been selected and entered for code Cd33, the user may then change
			code Cd35 to “bulb.” After bulb has been selected and entered, the user may then
			utilize function codes Cd36 and Cd37 to make the desired changes.
			This code is enabled only if in the dehumidification mode (code Cd33) and bulb
			mode (Cd35) has been set to “bulb”. If these conditions are not met, “alt” will be
			displayed (indicating that the evaporator fans will alternate their speed) and the
Cd36	Evaporator Speed		display cannot be changed. If a dehumidification set point has been selected along
	Select		with bulb mode then “alt” may be selected for alternating speed, “Lo” for low
			speed evaporator fan only, or “Hi” for high speed evaporator fan only. If a setting
			other than “alt” has been selected and bulb mode is deactivated in any manner,
			then selection reverts back to “alt.”
			This code, as with function code Cd36, is used with bulb mode and dehumidifica-
	Defrost Termination		tion. If bulb mode is active, this code allows the user to change the temperature
Cd37	Temperature Setting		defrost will terminate. It allows the user to change the setting within a range of
	(Bulb Mode)		4_C to 25.6_C in 0.1_C (0.2_F) increments. This value is changed using the UP/
			DOWN ARROW keys, followed by the ENTER key when the desired value is
			displayed. If bulb mode is deactivated, the DTS setting returns to the default.
			Display Only Functions - Continued
			Code Cd38 will display the current secondary supply temperature sensor reading
Cd38	Secondary Supply		for units configured for four probes. If the unit is configured with a DataCORD-
	Temperature Sensor		ER, Cd38 will display “----------.” If the DataCORDER suffers a failure,
			(AL55) Cd38 will display the supply recorder sensor reading.
			Code Cd39 will display the current secondary return temperature sensor reading
Cd39	Secondary Return		for units configured for four probes. If the unit is configured with a DataCORD-
	Temperature Sensor		ER, Cd39 will display “----------.” If the DataCORDER suffers a failure,
			(AL55) Cd39 will display the return recorder sensor reading.
	Container Identifica-		Code Cd40 is configured at commissioning to read a valid container identifica-
Cd40			tion number. The reading will not display alpha characters, only the numeric por-
	tion Number		tion of the number will display.
			SERVICE FUNCTION: This code is used for troubleshooting and allows manu-
Cd41	Valve Override		al positioning of the economizer, unloader, suction modulation and oil return
			valves. Refer to paragraph 6.19 for operating instructions.
Cd42	Oil Return Valve		The status of the valve is displayed (Open - Closed).

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