Mitsubishi SRK10CES, Техническое руководство

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(d) Prevention of continuous low speed operation: For oil return to compressor
(i) Operating condition:
When command speed of less than 26 rps continues for 60 minutes
(ii) Detail of operation: The unit is operated at command speed of 30 rps forcibly for 15 seconds. (The indoor and outdoor
fans are not changed.)
Note (1) When the command of exceeding 30 rps is directed during 30 rps forced operation, the unit follows it.
(e) Compressor protection start
(i) When the indoor unit calculated speed is 64 rps or over at operation start, the unit is operated with 64 rps for 1 minute and 45
seconds.
(ii)
After (i) above, if the decision speed is 96 rps or higher, it runs for 5 minutes at 96 rps, then changes to the decision speed.
(iii) At thermo operation (OFF
→
ON) this control is not executed.
(iv) The indoor unit fan corresponds to the command speed of each operation mode.
Note (1) When the calculated speed is less than 64 rps, the unit is started with low load starting described in article (e).
(f) Low load starting
(i)
When the unit is started with calculated speed of less than 30 rps, it is operated with 30 rps for 60 seconds, then the operation
is moved to the command speed.
(ii)
The indoor fan corresponds to the operation mode.
Cooling: Speed corresponding to the command speed of air flow switching
Dehumidification: Speed decided in the operation region
Heating: The lower one between the speed corresponding to the command speed and the hot keep speed
(g) Inching prevention
When the compressor goes into the thermo operation within 3 minutes since operation start or becomes various dehumidifying
operations, the operation is continued with the command speed of 12 rps forcibly.
(h) Current safe
(i) Purpose: Current is controlled not to exceed the upper limit of the setting operation current.
(ii) Detail of operation:
Input current to the converter is monitored with the current sensor fixed on the printed circuit board of
the outdoor unit and, if the operation current value reaches the limiting current value, the inverter speed is reduced.
If the mechanism is actuated when the speed of outdoor unit is less than 30 rps, the compressor is stopped immediately.
Operation starts again after a delay time of 3 minutes.
(i) Current cut
(i) Purpose:
Inverter is protected from overcurrent.
(ii) Detail of operation: Output current from the converter is monitored with a shunt resistor and, if the current exceeds the
setting value, the compressor is stopped immediately. Operation starts again after a delay time of 3 minutes.
(j) Heating overload protective control
(i) Operating conditions : When the unit is operating with the outdoor unit speed other than 0 rps or when the outdoor air
temperature (detected by Th5) rose beyond 17ºC for 2 minutes continuously.
(ii) Detail of operation
1)
Indoor fan speed is raised forcibly by 1 step. However, when the air flow is LO, the fan speed is not raised by 1 step.
2) Taking the upper limit of control speed range at 60 rps, if the output speed obtained with the fuzzy calculation exceeds the
upper limit, the upper limit value is maintained.
3) The outdoor fan is set on 2nd speed.
4) JET operation control does not raise the speed by 1 step
5)
The lower limit of control speed is set to 35 rps and even if the calculated result becomes lower than that after fuzzy
calculation, the speed is kept to 35 rps. However, when the thermo becomes OFF, the speed is reduced to 0 prs.
(iii) Reset condition: When the outdoor air temperature drops below 16ºC.