Ipm (Power Transistor) Protection Control; Compressor Protection Control (Gas Leak Detection Control 1); Compressor Protection Control (Gas Leak Detection Control 2) - Panasonic CU-3E19RBU-5 Service Manual


The first 30 minutes of cooling operation, (A) will be applied.

13.12 IPM (power transistor) Protection Control


Overheating Prevention Control
If IPM temperature rises to 176°F (80°C), outdoor fan speed will be increased.
o
When the IPM temperature rises to 203°F (95°C), compressor operation will stop immediately.
o
Compressor operation restarts when temperature decreases to 194°F (90°C).
o
If IPM temperature detected less than -22°F (-30°C), IPM is judged as open circuit ("F96" is indicated).
o

DC peak current control
When IPMDC current exceeds set value of 30.0 ± 3.0 A, the compressor will stop.
o
If the DC peak current detected within 30 seconds after operation starts, compressor will restart after
o
1 minute.
If the DC peak current detected 30 seconds or more after operation starts, compressor will restart after
o
2 minutes.
Within 30 seconds after compressor restarts, if the DC peak current is exceeded set value continuously for
o
7 times, all indoor and outdoor relays will be cut off ("F99" is indicated).

Error reset can be done by power supply reset.

13.13 Compressor Protection Control (Gas leak detection control 1)


Control start conditions
For 5 minutes, the compressor continuously operates and total current is low.
o
During Cooling or Soft Dry operation:
o
Indoor intake temperature — indoor piping temperature is below 39.2°F (4°C).
During Heating operation:
o
Indoor pipe temperature — indoor intake temperature is below 37.4°F (3°C).
Not during deice control.
o
Compressor ON with maximum frequency.
o

Control content
Compressor stops (and restart after 3 minutes)
o
If the conditions above happen 4 times within 60 minutes, the unit will stop operation ("F91" is indicated).
o

13.14 Compressor Protection Control (Gas leak detection control 2)


This control detect gas leakage condition to prevent compressor damage.

Control start condition
All connected indoor units capability supply ON.
o
Compressor ON with maximum frequency.
o
Not during annual cooling.
o
Compressor discharge temperature high.
o

Control content
Compressor OFF during this control ("F91" is memorized in EEPROM)
o
If the above conditions happen 2 times within 60 minutes, indoor units' Timer LED will blinks ("F91" is
o
indicated at all indoor units)
102.2°F (39°C)
Outdoor air temperature
(B)
(A) 100.4°F (38°C)
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