Carrier 48/50AJ Auto View of Run Status Display Table, Economizer Run Status Display Table

Cap Threshold Subtracting (Z.MIN) — This parameter is used in the calculation of SMZ and is calculated as follows:

Z.MIN = Configuration→COOL→Z.GN * (–10 + (4*

(–SUB.R))) * 0.6

Cap Threshold Adding (Z.PLU) — This parameter is used in the calculation of SMZ and is calculated as follows:

Z.PLU = Configuration→COOL→Z.GN * (10 + (4*

(–ADD.R))) * 0.6

High Temp Cap Override (H.TMP) — If stages of mechani- cal cooling are on and the error is greater than twice Y.PLU, and the rate of change of error is greater than 0.5° F, then a stage of mechanical cooling will be added every 30 seconds. This override is intended to react to situations where the load rapidly increases.

Low Temp Cap Override (L.TMP) — If the error is less than twice Y.MIN, and the rate of change of error is less than –0.5° F, then a mechanical stage will be removed every 30 sec- onds. This override is intended to quickly react to situations where the load is rapidly reduced.

Pull Down Cap Override (PULL) — If the error from set point is above 4° F, and the rate of change is less than –1° F per minute, then pulldown is in effect, and “SUM” is set to 0. This keeps mechanical cooling stages from being added when the error is very large, but there is no load in the space. Pulldown for units is expected to rarely occur, but is included for the rare situation when it is needed. Most likely pulldown will occur when mechanical cooling first becomes available shortly after the control goes into an occupied mode (after a warm unoccu- pied mode).

Slow Change Cap Override (SLOW) — With a rooftop unit, the design rise at 100% total unit capacity is generally around 30° F. For a unit with 4 stages, each stage represents about 7.5° F of change to EDT. If stages could reliably be cycled at very fast rates, the set point could be maintained very precisely. Since it is not desirable to cycle compressors more than 6 cy- cles per hour, slow change override takes care of keeping the PID under control when “relatively” close to set point.

MODE TRIP HELPER — The Mode Trip Helper table pro- vides information on the unit modes and when the modes start and stop. See Table 108. This information can be used to help determine why the unit is in the current mode.

CCN/LINKAGE DISPLAY TABLE — The CCN/Linkage display table provides information on unit linkage. See Table 109.

COMPRESSOR RUN HOURS DISPLAY TABLE — The Compressor Run Hours Display Table displays the number of run time hours for each compressor. See Table 110.

COMPRESSOR STARTS DISPLAY TABLE — The Com- pressor Starts Display Table displays the number of starts for each compressor. See Table 111.

TIME GUARD DISPLAY TABLE — The Time Guard Dis- play Table delay time for each compressor and heat relay. See Table 112.

SOFTWARE VERSION NUMBERS DISPLAY TABLE — The Software Version Numbers Display Table displays the software version numbers of the unit boards and devices. See Table 113.

Table 105 — Auto View of Run Status Display Table

ITEM	EXPANSION	RANGE	UNITS	POINT	WRITE STATUS
VIEW	AUTO VIEW OF RUN STATUS
HVAC	ascii string spelling out the hvac modes			string
OCC	Occupied ?	YES/NO		OCCUPIED	forcible
MAT	Mixed Air Temperature		dF	MAT
EDT	Evaporator Discharge Tmp		dF	EDT
LAT	Leaving Air Temperature		dF	LAT
EC.C.P	Economizer Control Point		dF	ECONCPNT
ECN.P	Economizer Act.Curr.Pos.	0-100	%	ECONOPOS
CL.C.P	Cooling Control Point		dF	COOLCPNT
C.CAP	Current Running Capacity			CAPTOTAL
HT.C.P	Heating Control Point		dF	HEATCPNT
HT.ST	Requested Heat Stage			HT_STAGE
H.MAX	Maximum Heat Stages			HTMAXSTG

Table 106 — Economizer Run Status Display Table

ITEM	EXPANSION	RANGE	UNITS	POINT	WRITE STATUS
ECON	ECONOMIZER RUN STATUS
ECN.P	Economizer Act.Curr.Pos.	0-100	%	ECONOPOS
ECN.C	Economizer Act.Cmd.Pos.	0-100	%	ECONOCMD	forcible
ACTV	Economizer Active ?	YES/NO		ECACTIVE
DISA	ECON DISABLING CONDITIONS
UNAV	Econ Act. Unavailable?	YES/NO		ECONUNAV
R.EC.D	Remote Econ. Disabled?	YES/NO		ECONDISA
DBC	DBC - OAT Lockout?	YES/NO		DBC_STAT
DEW	DEW - OA Dewpt.Lockout?	YES/NO		DEW_STAT
DDBC	DDBD- OAT > RAT Lockout?	YES/NO		DDBCSTAT
OAEC	OAEC- OA Enth Lockout?	YES/NO		OAECSTAT
DEC	DEC - Diff.Enth.Lockout?	YES/NO		DEC_STAT
EDT	EDT Sensor Bad?	YES/NO		EDT_STAT
OAT	OAT Sensor Bad ?	YES/NO		OAT_STAT
FORC	Economizer Forced ?	YES/NO		ECONFORC
SFON	Supply Fan Not On 30s ?	YES/NO		SFONSTAT
CLOF	Cool Mode Not In Effect?	YES/NO		COOL_OFF
OAQL	OAQ Lockout in Effect ?	YES/NO		OAQLOCKD
HELD	Econ Recovery Hold Off?	YES/NO		ECONHELD
O.AIR	OUTSIDE AIR INFORMATION
OAT	Outside Air Temperature		dF	OAT	forcible
OA.RH	Outside Air Rel. Humidity		%	OARH	forcible
OA.E	Outside Air Enthalpy			OAE
OA.D.T	OutsideAir Dewpoint Temp		dF	OADEWTMP

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