Toshiba RAV-SM2246AT8J-E Service Manual page 59

7. Heat sink temperature detection control
1) IGBT overheating prevention is protective control performed by a thermistor (TH sensor) in proximity to
IGBT.
2) When a temperature of TH e" 83°C is detected, the fan tap is moved by 1 step up.
Thereafter step-up is performed at a rate of +1 tap/5 seconds until a maximum fan tap is reached.
3) After 2) above, operation is returned to normal fan control at a temperature of TH < 78°C.
4) Operation of the compressor is terminated at a temperature of TH e" 100°C.
5) Operation is restarted after 2 minutes and 30 seconds using [1] as the trouble count. However a count of
[4] in the same operation confirms a trouble.
The check code display is "P07" (Restart will not be performed).
∗ When trouble is confirmed, this may be a trouble caused by heat build-up or blower fan failure in the outdoor
unit, or a trouble in the IPDU board.
8. Electrical current release value shift control
1) This control is for the purpose of preventing malfunction
of the compressor or electronic components such as
the IGBT of the inverter in the compressor drive system
during cooling operations.
2) Select the current release control value (I1) by TO
sensor value from the right table.
9. Over-current protective control
1) Operation of the compressor is stopped when the over-current protective circuit detects a trouble current.
2) The compressor restarts after 2 minutes 30 seconds using [1] as a trouble count.
After restart, the trouble count is cleared when operation continues for 6 minutes or more.
3) A trouble is confirmed when the trouble count takes a value of [8].
4) For the indicated contents of trouble, confirm using the check code table.
10. High-pressure switch/Compressor case thermostat control
1) When the high-pressure switch or the compressor case thermostat operates, the operation of the
compressor is terminated.
2) The compressor restarts after 2 minutes 30 seconds using [1] as a trouble count.
After restart, the trouble count is cleared when operation continues for 10 minutes or more.
3) A trouble is confirmed with the trouble count [10].
4) For the indicated contents of trouble, confirm using the check code table.
11. High-pressure release control
1) The operation frequency is controlled to restrain abnormal rising of high pressure by TL sensor in cooling
operation and TC sensor in heating operation.
2) When TL sensor in cooling operation or TC sensor in heating operation detects abnormal temperature of
the stop zone, stop the compressor and the trouble count becomes +1.
3) When the compressor stopped with 2), the operation restarts from the point of the normal operation zone
(e point or lower) where it returned after 2 minutes 30 seconds.
4) The trouble count when the compressor stopped with 2) is cleared after the operation continued for 10
minutes. If the trouble count becomes [10] without clearing, the trouble is determined and reactivation is
not performed.
5) For the check code display contents, confirm on the check code list.
HEAT TC / COOL TL
[˚C]
a
b
c
d
Frequency slow up (Up to command)
e
Abnormal stop
Frequency normal down
Frequency slow down
Frequency hold
As command is
The correction is based on the table below:
Temp. range
50˚C ≤ TO
47˚C ≤ TO < 50˚C
44˚C ≤ TO < 47˚C
39˚C ≤ TO < 44˚C
TO < 39˚C
TO trouble
a
b
c
d
e
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SM224 SM280
9.0A 9.0A
11.0A 11.0A
14.0A 14.0A
15.7A 17.6A
15.7A 18.6A
9.0A 9.0A
HEAT COOL
TC TL
62˚C 63˚C
57˚C 62˚C
55˚C 60˚C
53˚C 58˚C
49˚C 54˚C