Mitsubishi SCM80ZA Manual page 34

(j) Outdoor unit abnormal stop and compressor motor protection
If the air conditioner is operating at an inverter frequency 30 Hz or more and an input current of 1 A or less is detected for 30
continuous seconds or more, a abnormal stop is performed. At the same time, LED 2 on the printed circuit board for the
outdoor unit will flash 2 times at a 0.5 second interval every 8 seconds.
The unit is re-started after 3-minute's delay, however, if the re-start has been performed 4 times within 1 hour, the fifth start
cannot be performed. (The timer lamp on the indoor unit will flash 2 times.)
(k) Discharge pipe thermistor interrupt protection
After 10 minutes from the compressor operation start other than 0 Hz of outdoor unit, when the temperature of discharge
pipe thermistor detected the open circuit signal for 10 seconds (less than 7°C), the stop mode is performed immediately
and then the unit is re-started.
(This is detected only once at the compressor ON condition.)
If abnormality occurred 4 times in succession, the abnormal stop is performed and the re-start is not performed. At the
same time, the LED 2 on the printed circuit board of the outdoor unit will be lit for 4 seconds and lit off for 4 seconds.
(The timer lamp on the indoor unit flashes twice.)
(l) Power transistor overheat protection
If the thermal switch inside the power transistor is activated, the compressor is stopped immediately. While the unit can be
restarted once temperature of the power transistor has gone down and/or after the 3-minute delay has finished, it cannot be
started a third time if there is an abnormal stop of a restart within 1 hour. At the same time, LED 5 on the printed circuit board
for the outdoor unit will flash 4 times at a 0.5 second interval every 8 seconds. (The timer lamp on the indoor unit will flash
4 times.)
Set value: 110 ± 10°C open / 90°C close
(m) Compressor overheat protection control
1) When the compressor thermo (51C) is OFF for 10 continuous seconds, the inverter is stopped.
After that, when the compressor thermo (51C) becomes ON for 10 continuous seconds, the inverter is re-started.
2) When the discharge pipe thermistor temperature is 115°C for 5 continuous seconds, the inverter is stopped. If the
temperature becomes 90°C after stop mode, the inverter is re-started.
3) If the inverter stop occurs 4 times within 1 hour, the abnormal stop is performed and the re-start is not performed.
(The LED 5 on the printed circuit board of the outdoor unit will flash 5 times every 8 seconds at a 0.5 second's interval
for 5 times. The timer lamp on the indoor unit will flash 5 times.)
4) When the detected temperature is 100°C, the following frequency control is performed.
Decision frequency
Inverter
Notes (1) If the discharge pipe temperature is 100°C, the frequency is lowered 4 Hz.
(2) After 40 seconds, if the discharge pipe temperature is lower than the previous temperature, the frequency is lowered 2 Hz; if it is higher, the
frequency is lowered 4 Hz.
(3) If the discharge pipe temperature is 90°C or more and less than 100°C and the inverter frequency is maintained and/or the unit operates at the
same frequency for 6 minutes or more, compressor overheat protection control is cancel and the unit returns to normal operation.
84
6 minutes or more has passed
6 minutes or more has passed
6 minutes or more has passed
90
Discharge pipe temperature (°C)
: http://splitoff.ru/tehn-doc.html
4 Hz
(3)
4 Hz or 2 Hz
(3)
Lower limit 30 Hz
(3) 4 Hz or 2 Hz
0 Hz
100 115
(2)
(2)