Mitsubishi Heavy Industries V Multi FDC71VNX Technical Manual page 131

(g) Over-current protection current safe controls I, II
Detecting the outdoor inverter input (primary) current and the output (secondary) current, if the current values exceed
setting values, the compressor speed (frequency) is controlled to protect the inverter.
Retention
Reset
B
Current (A)
(Fig. C) The control value "A" and the reset value vary depending
on the compressor speed.
24
22
20
18
16
Reset valve B
14
12
40 50 60 70
Compressor speed (frequency) (rps)
(h) Power transistor temperature protection
(i) Protective control
If the power transistor temperature (detected with TIP) exceeds the setting value, the compressor speed (frequency)
is controlled to suppress the rise of power transistor temperature.
Reset
81
Power transistor temperature (°C)
(i) Anomalous power transistor current
(i) Prevents over-current on the inverter. If the current value in the power transistor exceeds the setting value, the
compressor stops.
(ii) If the current value in the power transistor exceeds the specified value and the compressor stops 4 times within 30
minutes, E42 is displayed on the remote control and it enters the anomalous stop mode.
(j) Anomalous inverter PCB
If the power transistor detects any anomaly for 15 minutes, including the stop of compressor, E51 is displayed on the
remote control and it enters the anomalous stop mode.
(k) Anti-frost control by the compressor frequency control
(i) If the indoor heat exchanger temperature (detected with Thi-R) exceeds the setting value at 4 minutes after the
start of compressor, the compressor speed (frequency) is controlled to initiate the anti-frost control of indoor heat
exchanger.
(ii) When there are 2 indoor heat exchanger temperatures (Thi-R), the lowest temperature is detected.
Reduces compressor frequency
at each minute.
(iii) Regarding the anti-frost control by the operation stop, refer to the operation control function by the indoor control
and the cooling, dehumidifying frost prevention of page 18.
Reduces frequency
at each minute.
Primary
current
A
side
Secandary
current
side
Note (1) Value in ( ) are for the single phase models.
Control valve A
80 90 100 110 120 130
Reduces compressor frequency
at each minute.
Retention
85
Reset
Retention
1.5 3.5
Indoor heat exchanger temperature (°C)
130
-
Cooling
Model
Control
value A
FDC71 15.0
FDC100 11.0 (23.0) 10.0 (22.0) 11.0 (23.0) 10.0 (22.0)
FDC125, 140 11.0 (23.0) 10.0 (22.0) 11.0 (25.0) 10.0 (24.0)
FDC71 13.0
FDC100 11.5 (Fig.C) 10.5 (Fig.C) 11.5 (Fig.C) 10.5 (Fig.C)
FDC125, 140 11.5 (Fig.C) 10.5 (Fig.C) 11.5 (Fig.C) 10.5 (Fig.C)
-
'19 • PAC-T-327
Heating
Reset Control Reset
value B value A value B
14.0 16.0 15.0
12.0 13.0 12.0