Carrier 50XJ064-104 specifications Alarms Displayed at Unit LID

Table 20 — Alarms Displayed at Unit LID

FUNCTION	ALARM MESSAGE (Actual Text)	CAUSE	UNIT RESPONSE (See Notes)		RESET
SAT	SAT xx.x dF outside	SAT reads out of prescribed range	Unit shuts down and		Automatic
	limit of xxx.x dF	for 5 sec. during operation	indicates alarm
DSP_ALM	Duct Static Sensor Failure	Duct Pressure Sensor reading is out of	Unit shuts down,	indicates alarm	Automatic
		range (i.e., likely faulty sensor or circuit).
FSD	Fire Shutdown	External Fire Alarm input opens for 5 sec.	Unit shuts down,	indicates alarm	Automatic
	Duct High Static Pressure	Pressure rises above 3.0 in.H2O during	Unit shuts down,	indicates alarm	Automatic
DHS		operation. Set point adjustable on the switch.
		Used for Off position of switch on smaller
		units with one controller
CSMUX	CSMUX x.xx Volts outside	Compressor safety circuit Resistor Board	Unit shuts down and indicates		Automatic
	limit of x.xx Volts	reads out of prescribed range for 5 sec.	alarm
		during operation
CDWF	Check Condenser Water Flow	Waterflow Switch contacts are open at startup,	Compressor Cooling shuts down,		Automatic
		or go open for 5 sec. during operation.	locks out and indicates warning
FLTS	Change Filters	Filter pressure drop exceeds Filter Pressure	Unit operates normally,		Automatic
		Switch setting (and contacts open) for 5 sec.	but still indicates Warning
	Economizer Freeze Condition	Economizer Freeze Switch contacts for 5 sec.	Warning indicated for 15 minutes		Automatic
FREEZ		open during operation.	turns off ventilation request, then
			unit shuts down and Econo valve
			opens, pump request stays on,
			and Alarm indicated
C1_ALM	Compressor 1 Fault	Compressor safety circuit opens for 2 sec.	Unit shuts that compressor down,		Automatic
C2_ALM	Compressor 2 Fault		and indicates Warning, but retries
C3_ALM	Compressor 3 Fault		2 more times before locking it out.
C4_ALM	Compressor 4 Fault
	Check Supply Fan	Duct Pressure Sensor reading is below .3 in.	If on but indicates off cooling,		Automatic
SFS		H2O at 10 sec. after starting fan, or during	and heating will be disabled
		operation, or reads above .3″ when fan is	warning light will be on
		supposed to be Off.
EWT	EWT xx.x dF outside	EWT reads out of prescribed range for 5 sec.	Indicates warning		Automatic
	limit of xxx.x dF	or more
MA_RA	MA_RA xx.x dF outside	ma_ra reads out of prescribed range for 5 sec.	Indicates warning		Automatic
	limit of xxx.x dF	or more
PHASE	Phase Loss	Phase monitor activates (see “Phase	Unit shuts down,	indicates alarm	Automatic
		Loss/Reversal Protection Switch” on page 5)
		for 5 sec. during operation.
BYPAS		BYPAS switch in Bypass position or Off,
		local remote in Off position

NOTES:

1.Unit display will indicate alarm by displaying “There is 1 Alarm” or “There are X alarms”, for the active alarms in the controller.

2.Red light on, indicating alarm.

3.Yellow light is on, indicating a warning.

Standard Diagnostic Features, Alarm and Warning Lights

SUPPLY AIR TEMPERATURE SENSOR FAILURE — If the supply air temperature sensor fails and indicates either 245 F from a short or -40.0 F from and open sensor the control- ler outputs will be forced to off with safety forces, the alarm output will close and the red Alarm light will be lit. A system alarm will be generated and displayed on the unit keypad. Unit reset is automatic when the supply air sensor has a valid reading again.

DUCT STATIC PRESSURE SENSOR FAILURE — If the duct static pressure sensor fails and indicates either 5.0 inches from a short or 0.0 inches from and open sensor the controller outputs will be forced to off with safety forces, the alarm output will close and the red Alarm light will be lit. A system alarm will be generated and displayed on the unit keypad. Unit reset is automatic when the supply air sensor has a valid reading again.

FIRE/SHUTDOWN INPUT (FSD) — This is a normally closed input, which when opened, deenergizes an isolation relay in the unit, opening the input to the controller. When this input turns opens, all control outputs are immediately turned off, including the fan. Fire forces will be displayed on the outputs. Unit reset is automatic when the FSD input is closed

again. A system alarm will be generated and displayed at the keypad.

DUCT HIGH STATIC INPUT (DHS) — This air switch provides over pressurization protection for the ductwork. It is factory installed in the unit. The switch is a normally open switch, with adjustable manual setting (range is 1 to 5 in. wg default setting is 3.0 in. wg). Upon switch closure, the control- ler outputs will be forced to off with safety forces, the alarm output will close and the red Alarm light will be lit. A system alarm will be generated and displayed on the unit keypad. Unit reset is automatic when the duct pressure is again below the switch setting minus the device hysteresis.

COMPRESSOR MULTIPLEX (MUX) BOARD — A re- sistance board is used to generate a variable voltage input to the controller to determine compressor status. If the voltage output from this board gets out of the acceptable range the controller outputs will be forced to off with safety forces, the alarm output will close and the red Alarm light will be lit. A system alarm will be generated and displayed on the unit keypad. Unit reset is automatic when the Mux board has a valid reading again. The valid range is between 1.5 and 10 vdc. The table below indicates what voltages correspond to the compressor status indicated in the controller.

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