Discharge Temperature Release Control; Current Release Control - Carrier 30AWH004HB Service Manual

Discharge temperature release control

1) This function controls the compressor frequency, when the discharge temperature has increased due to max load
condition or during PMV control. It subdivides the frequency control up to a unit of 0.6 Hz to stabilize the cycle.
2) When the discharge temperature is detected in an abnormal stop zone, the unit stops the compressor and restarts it after
2 minutes, 30 seconds (time guard). The error count is cleared when operation of 10 minutes without error occurs. If the
abnormal stop zone has been detected 4 times without clearing, an error code is displayed.
* Possible causes include excessive amount of refrigerant, defective PMV, or blockage in the refrigeration cycle.
30AWH004
30AWH006
30AWH008
30AWH012
30AWH015

Current release control

The output frequency and the output voltage are controlled by AC current detected on the P.C. board.
The max current value of the inverter are shown in table below.
[A]
Hold
Normal operation
SM_30AW.indd 64
TD[ C]
Error stop ("P03" displayed after 4 error counts)
a
b
c
d
e
As command
a b
117 112
117 112
117 107
111 106
111 109
Frequency down
Hold
Control management
Frequency down
Frequency holding
Frequency slow-up
(Based on command)
c d e
108 105 98
108 105 98
103 100 93
100 95 90
106 103 96
l1 value [A]
COOL
30AWH004 6.3
30AWH006 8.5
30AWH008 10.1
30AWH012 23
30AWH015 20
64
TD: Discharge
temperature
HEAT
6.3
10.8
12
23
20
5
30AW
14-03-2011 14:45:11