Toshiba RAV-SM2804AT7 Heat sink temperature detection control, Over-current protective control

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 ≥ 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 ≥ 100°C.

5)Operation is restarted after 2 minutes and 30 seconds using [1] as the error count. However a count of [4] in the same operation confirms an error. The error display is “P07” (Restart will not be performed).

∗When error is confirmed, this may be an error caused by heat build-up or blower fan failure in the outdoor unit, or an error 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.

The correction is based on the table below:

Temp. range		SM224	SM280
50°C ≤	TO	9.0	9.0
47°C ≤	TO < 50°C	11.0	11.0
44°C ≤	TO < 47°C	14.0	14.0
TO < 44°C		15.7	17.6
TO error		9.0	9.0

9.Over-current protective control

1)Operation of the compressor is stopped when the over-current protective circuit detects an error current.

2)The compressor restarts after 2 minutes 30 seconds using [1] as an error count.

After restart, the error count is cleared when operation continues for 6 minutes or more.

3)An error is confirmed when the error count takes a value of [8].

4)For the indicated contents of error, 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 an error count.

After restart, the error count is cleared when operation continues for 10 minutes or more.

3)An error is confirmed with the error count [10].

4)For the indicated contents of error, 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 error 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 error count when the compressor stopped with 2) is cleared after the operation continued for

10 minutes. If the error count becomes [10] without clearing, the error is determined and reactivation is not performed.

5)For the error display contents, confirm on the check code list.

HEAT TC / COOL TL

a	[°C]	Abnormal stop
		Frequency normal down
b
		Frequency slow down
c
		Frequency hold
d
		Frequency slow up (Up to command)
e
		As command is

	HEAT	COOL
	TC	TL
a	62°C	63°C
b	57°C	62°C
c	55°C	60°C
d	53°C	58°C
e	49°C	54°C

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