Midea M4OC-36HRDN1-M - Protection Mechanisms; Compressor Restart Delay Protection; Compressor Discharge Temperature Protection; Low Voltage Protection

8.4.6 Opening degree of electronic expansion valve:
Actual opening degree equals the display data divided 8
8.5 Protection
8.5.1 Three minutes delay at restart for compressor.
8.5.2 Temperature protection of compressor discharge.
When the compressor discharge temp. is getting higher, the running frequency will be limited as below rules:
----If 102℃<T5<115℃, decrease the frequency to the lower level every 2 minutes till to F1.
---If T5>115 ℃ for 10 seconds, the compressor will stop and restart till T5<90℃.
8.5.3 Low voltage protection
VOLLIMT1
VOLTAGE
No limit
VOLLIMT2
VOLLIMT3
Off
VOLFRE2
VOLFRE1
VOLREL1
VOLREL2
VOLREL3
Model VOLLIMT1 VOLLIMT2 VOLLIMT3 VOLREL1 VOLREL2 VOLREL3 VOLFRE1 VOLFRE2
M2OC-18HRDN1-M 230 200 120 260 210 135 62 54
M3OC-27HRDN1-M 245 220 120 265 240 135 78 45
M4OC-36HRDN1-M 200 185 120 210 195 135 54 42
Note: if the low voltage protection occurs and not resumes within 3min, it will keep the protection always
after restart the machine.
8.5.4 Compressor current limit protection
If the compressor current exceeds the current limit value for 10 seconds, the compressor frequency will be
limited as below table.
Cooling mode:
Current frequency(Hz) Current limit value(A) Frequency limit
COOL_F10 ICOOLLMT6
Decrease the frequenc
y to COOL_F4 and run at
COOL_F4 for 3 minutes.
After that, the frequency will be adjusted according to the
capacity demand and rise to the upper level every 3
minutes
(When the frequency>COOL_F4 via capacity demand).
COOL_F9 ICOOLLMT5
COOL_F8 ICOOLLMT4
COOL_F7 ICOOLLMT3
COOL_F6 ICOOLLMT2
COOL_F5 ICOOLLMT1
If the current frequency is lower than COOL_F4, the frequency will not be limited.
After 10s of the compressor start, if the current>ICOOL,the AC will display the failure for 30 seconds and stop. The AC will restart 3
minutes later.
Heating mode:
Current frequency(Hz) Current limit value(A) Frequency limit
HEAT_F12 IHEATLMT8 Decrease the frequency to HEAT_F4 and run at HEAT_F4
for 3 minutes.
After that, the frequency will be adjusted according to the
capacity demand and rise to the upper level every 3
minutes
HEAT_F11 IHEATLMT7
HEAT_F10 IHEATLMT6
HEAT_F9 IHEATLMT5
HEAT_F8 IHEATLMT4