Carrier 48AJ Operating And Service Manual page 43

STAGE
0 1
COMP
A1 OFF ON
A2 OFF OFF
B1 OFF OFF
B2 OFF OFF
UNIT
030 0% 23%
035,036 0% 22%
040,041 0% 21%
050 0% 23%
051 0% 25%
060 0% 24%
Table 54 — Staging Sequence With Hot Gas Bypass — 48/50AK,AY030-060
STAGE
0 1
COMP
A1 OFF ON*
A2 OFF OFF
B1 OFF OFF
B2 OFF OFF
UNIT
030 0% 12%
035,036 0% 12%
040,041 0% 13%
050 0% 16%
051 0% 19%
060 0% 19%
*With minimum load valve ON.
COOLING MODE DIAGNOSTIC HELP — To quickly de-
termine the current trip points for the cooling modes, the Run
Status sub-menu at the local display allows the user to view the
calculated start and stop points for both the cooling and heating
trip points. The following sub-menu can be found at the local
→
display under Run Status TRIP. See Table 55.
Table 55 — Run Status Mode Trip Helper
ITEM EXPANSION
TRIP MODE TRIP HELPER
UN.C.S Unoccup. Cool Mode Start
UN.C.E Unoccup. Cool Mode End
OC.C.S Occupied Cool Mode Start
OC.C.E Occupied Cool Mode End
TEMP Ctl.Temp RAT,SPT or Zone
OC.H.E Occupied Heat Mode End
OC.H.S Occupied Heat Mode Start
UN.H.E Unoccup. Heat Mode End
UN.H.S Unoccup. Heat Mode Start
HVAC the current HVAC MODE
The controlling temperature is "TEMP" and is in the middle
of the table for easy reference. The HVAC mode can also be
viewed at the bottom of the table.
SUMZ COOLING ALGORITHM — The SumZ cooling algo-
rithm is an adaptive PID which is used by the control whenever
more than 2 stages of cooling are present (C.TYP = 1,2,3, and
5). This section will describe its operation and define the perti-
nent parameters. It is generally not necessary to modify parame-
ters in this section. The information is presented primarily for
reference and may be helpful for troubleshooting complex oper-
ational problems.
The only configuration parameter for the SumZ algorithm is
located at the local
→ →
COOL Z.GN. See Table 47.
Table 53 — Staging Sequence Without Hot Gas Bypass —
48/50AK,AY030-060 and Multi-Stage 48/50AJ,AW030-060
SEQUENCE 1
2 3
Compressor Status
ON OFF ON
ON ON ON
OFF ON ON
OFF OFF OFF
Unit Capacity 48/50A
45% 50% 73%
48% 52% 74%
43% 50% 71%
46% 46% 68%
50% 50% 75%
50% 50% 74%
SEQUENCE 1
2 3 4
Compressor Status
ON ON OFF
OFF ON ON
OFF OFF ON
OFF OFF OFF OFF
Unit Capacity 48/50A
23% 45% 50% 73%
22% 48% 52% 74%
21% 43% 50% 71%
23% 46% 46% 68%
25% 50% 50% 75%
24% 50% 50% 74%
CCN
UNITS
POINT
dF UCCLSTRT
dF UCCL_END
dF OCCLSTRT
dF OCCL_END
dF CTRLTEMP
dF OCHT_END
dF OCHTSTRT
dF UCHT_END
dF UCHTSTRT
String
display under Configuration
4 5 0
ON OFF
ON OFF
ON OFF
ON OFF
100% 0%
100% 0%
100% 0%
100% 0%
100% 0%
100% 0%
5 6 0 1
ON ON OFF OFF
ON ON OFF ON*
ON ON OFF OFF
ON OFF OFF
100% 0% 12%
100% 0% 16%
100% 0% 13%
100% 0% 16%
100% 0% 19%
100% 0% 21%
Capacity Threshold Adjust (Z.GN) — This configuration is
used on units using the "SumZ" algorithm for cooling capacity
control (Configuration
affects the cycling rate of the cooling stages by raising or
lowering the threshold that capacity must build to in order to
add or subtract a stage of cooling.
The cooling algorithm's run-time variables are located at
the local display under Run Status
Current Running Capacity (C.CAP) — This variable repre-
sents the amount of capacity currently running in percent.
Current Cool Stage (CUR.S) — This variable represents the
cool stage currently running.
Maximum Cool Stages (MAX.S) — This variable is the max-
imum number of cooling stages the control is configured for
and capable of controlling.
Active Demand Limit (DEM.L) — If demand limit is active,
this variable will represent the amount of capacity that the
control is currently limited to.
Capacity Load Factor (SMZ) — This factor builds up or
down over time (–100 to +100) and is used as the means of
adding or subtracting a cooling stage during run time. It is a
normalized representation of the relationship between "Sum"
and "Z".
Next Stage EDT Decrease (ADD.R) — This variable repre-
sents (if adding a stage of cooling) how much the temperature
should drop in degrees depending on the R.PCT calculation
and exactly how much additional capacity is to be added.
ADD.R = R.PCT * (C.CAP — capacity after adding a cooling
stage)
For example: If R.PCT = 0.2 and the control would be
adding 20% cooling capacity by taking the next step up,
0.2 times 20 = 4 F (ADD.R).
43
SEQUENCE 2
1 2 3
Compressor Status
OFF ON ON
ON ON OFF
OFF OFF OFF
OFF OFF ON
Unit Capacity 48/50A
23% 45% 50%
26% 48% 48%
21% 43% 50%
23% 46% 54%
25% 50% 50%
26% 50% 50%
SEQUENCE 2
2 3 4
Compressor Status
OFF ON ON
ON ON OFF
OFF OFF OFF
ON OFF ON
Unit Capacity 48/50A
23% 45% 50%
26% 48% 48%
21% 43% 50%
23% 46% 54%
25% 50% 50%
26% 50% 50%
→ →
UNIT C.TYP = 1, 2, 3 and 5). It
→
COOL. See Table 56.
4 5
ON ON
ON ON
OFF ON
ON ON
73% 100%
74% 100%
72% 100%
77% 100%
75% 100%
76% 100%
5 6
ON ON
ON ON
OFF ON
ON ON
73% 100%
74% 100%
72% 100%
77% 100%
75% 100%
76% 100%