Mitsubishi Heavy Industries FDCW100VNX-A, Technical Manual

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Service
‘19 • HM-T-340
b) Anomalous stop control
i) When a value detected by the low pressure sensor (LPT) satisfi es any of the following conditions, compressor stops.
①
When the low pressure drops to 0.079MPa or lower for 15 seconds continuously.
ii) Under any of the following conditions, LP alarm is displayed and E49 is recorded in Error Log, and it enters the
anomalous stop mode.
①
When the low pressure drops and the compressor stops under any of above conditions 3 times within 60 minutes.
②
When the low pressure sensor detects 0.079MPa for 5 minutes continuously including the time of compressor stopping
③
However, when the control condition
①
is established during the control of the compressor protection start
Ⅲ
, LP alarm
is displayed and E49 is recorded in Error Log at the fi rst stop of compressor and it enters the anomalous stop mode.
6) Overcurrent protection
＜ FDCW60VNX ＞
When the inverter primary current (CT current) reaches following value, the compressor speed
is reduced until it gets to the cancellation value.
Operation mode Current (A)
Cooling 11.5
Heating 13.5
＜ FDCW71, 100, 140VNX ＞
a) Current safe control I
When the inverter primary current (CT current) reaches following value, the compressor speed
is reduced until it gets to the cancellation value.
Model Operation Mode Current (A)
FDCW71VNX
Cooling 15
Heating 16
FDCW100VNX
Cooling 17
Heating 17
FDCW140VNX
Cooling 23
Heating 25
b) Current safe control II
Detecting the outdoor inverter output (secondary side) current, if the current values exceed setting values, the
compressor speed (frequency) is controlled in order to protect the inverter.
B
A
Reduce compressor speed
at every 1minute
Reset
Current (A)
Retention
12
14
16
18
20
22
24
50 40 60 70 80 90 100 110 120 130 Control or reset valve (A)
Compressor speed (frequency) (rps)
(Fig. C) The control value “A” and the reset value vary depending
on the compressor speed.
Reset valve B
Control valve A
Model
Cooling Heating
Control value A Reset value B Control value A Reset value B
FDCW71VNX 13 12 13 12
FDCW100VNX
Fig. C Fig. C Fig. C Fig. C
FDCW140VNX
7) Power transistor temperature control
This control monitors the power transistor temperature (TIP) from the start operation of compressor, and when the
following condition is established, compressor speed (frequency) is controlled.
Power transistor temperature (°C)
Reset
Retention
Reduce compressor speed
at every 1 minute.
77 80
70
73
FDCW100VNX
81
85 FDCW71VNX
FDCW140VNX
Operation control function by the outdoor unit control