Mitsubishi Heavy Industries SRK100VNXWZRF Service Manual page 159

(f) Over-current protection current safe controls I, II
Detecting the outdoor unit inverter input (primary) current and the output (secondary) current, if the current values
exceed setting values, the compressor speed 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
14
12
Outdoor air temp.43℃
10
40 50 60
Compressor speed (rps)
(g) Anomalous power transistor current
1) Prevents over-current on the inverter. If the current value in the power transistor exceeds the setting value, the
compressor stops.
2) 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.
(h) 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.
( i ) Anti-frost control by the compressor speed control
(i) If the indoor heat exchanger temperature (detected with Th2) exceeds the setting value at 4 minutes after the start
of compressor, the compressor speed is controlled to initiate the anti-frost control of indoor heat exchanger.
(ii) When there are 2 indoor heat exchanger temperatures (Th2), the lower temperature is detected.
(iii) Regarding the anti-frost control by the operation stop, refer to the operation control function by the indoor unit
control and the cooling, dehumidifying frost prevention of page 15.
( j ) Dewing prevention control
[Control condition]
During cooling and dehumidifying operation, if all the following conditions are established, the compressor speed
is reduced to prevent dewing and water splash.
➀ Cooling electronic expansion valve aperture (EEVC) is 500 pulses.
➁ Suction overheat is 10°C or higher.
➂ Compressor speed is 60 rps or higher.
[Control contents]
➀ When the suction overheat is 10°C or higher, the compressor speed is reduced at each 1 minute.
➁ Compressor speed does not rise till the cooling expansion valve becomes 460 pulses.
➂ This control takes 60 rps as its lower limit so that compressor speed is not controlled when it is less than 60 rps.
Reduces compressor speed
at each minute.
A
Outdoor air temp.35℃
70 80 90 100 110 120 130
Reduces compressor speed
at each minute.
Indoor heat exchanger temperature (°C)
158
-
Cooling
Model
Control
value A
Primary
FDC
current 100 13.5 (23.0) 12.5 (22.0) 13.5 (23.0) 12.5 (22.0)
side
Secandary
FDC
current 100 12.0 (Fig.C) 11.0 (A-1) 12.0 (23)
side
Note Value in ( ) are for the single phase models.
Reset
Retention
1.5 3.5
-
'22 • PAC-SM-422
Heating
Reset Control Reset
value B value A value B
11.0 (22)