Toshiba RAV-SM1603DT-A service manual Outdoor Controls, Requirement, Outline of Main Controls, 64

8. CIRCUIT CONFIGURATION AND CONTROL SPECIFICATIONS

8-1. Outdoor Controls

8-1-1. Outline of Main Controls

1.Pulse Motor Valve (PMV) control

1)For PMV with 45 to 500 pulses during operation, respectively.

2)In cooling operation, PMV is controlled with the temperature difference between TS sensor and TC sensor.

3)In heating operation, PMV is controlled with the temperature difference between TS sensor and TE sensor.

4)For the temperature difference in items 2) and 3), 1 to 5K is aimed as the target in both cooling and heating operations.

5)When the cycle excessively rose in both cooling and heating operations, PMV is controlled by TD sensor. The aimed value is usually 92°C for SM160 in both cooling and heating operations.

REQUIREMENT

A sensor trouble may cause a liquid back-flow or abnormal overheat resulting in excessive shortening of the compressor life. In a case of trouble on the compressor, be sure to check there is no error in the resistance value an the refrigerating cycle of each sensor after repair and then start the operation.

2. Discharge temperature release control TD [˚C]

1)This function controls the operation frequency, that is, lowers the operation frequency when the

discharge temperature has not lower or the						Error stop ("P03" display with 4 times of error counts)
						a
discharge temperature has rapidly risen during
							Frequency down
PMV control. It subdivides the frequency control						b
up to a unit of 0.6 Hz to stabilize the cycle.
2) When the discharge temperature is detected in an						c
abnormal stop zone, the unit stops the compres-							Frequency holding
sor and restarts after 2 minutes 30 seconds. The
error counter is cleared when it has continued the						d
operation for 10 minutes.							Frequency slow-up
If the abnormal stop zone has been detected by 4
							(Up to command)
times without clearing of counter, an error “P03” is						e	As command is
displayed.
∗ The cause is considered as excessively little
amount of refrigerant, defective PMV, or clogging
of cycle.
					[°C]	Current [A]
	a	b	c	d	e
SM160	111	106	100	95	90		Frequency down
						I1
							Hold
3. Current release control						I1–0.5	Hold
							Normal operation
The output frequency and the output voltage are
controlled by AC current value detected by T02 on the
outdoor P.C. board so that input current of the inverter
does not exceed the specified value.

Objective model

SM160

COOL HEAT

I1 value [A]

24.69

28.80

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