Toshiba RAV-SM560AT-E, RAV-SM800AT-E Requirement, 57, Pulse Modulating Valve PMV control

Models: RAV-SM800BT-E RAV-SM560BT-E RAV-SM560AT-E RAV-SM560UT-E RAV-SM800UT-E RAV-SM800AT-E

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1.Pulse Modulating Valve (PMV) control

9-2-2. Outline of Main Controls

1.Pulse Modulating Valve (PMV) control

1)For PMV, SM560 is controlled with 45 to 500 pulses and SM800 with 50 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 105°C for SM560 and 100°C for SM800 in both cooling and heating opera- tions.

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

 

1)

This function controls the operation frequency,

TD [ C]

 

that is, lowers the operation frequency when

 

the discharge temperature has not lower or

 

 

the discharge temperature has rapidly risen

Error stop ("P03" display with 4 times of error counts)

 

during PMV control. It subdivides the fre-

 

a

 

quency control up to a unit of 0.6Hz to stabi-

 

Frequency down

 

lize the cycle.

 

b

2) When the discharge temperature is detected

 

 

in an abnormal stop zone, the unit stops the

c

 

compressor and restarts after 2 minutes 30

Frequency holding

 

seconds. The error counter is cleared when it

 

 

has continued the operation for 10 minutes.

d

 

If the abnormal stop zone has been detected

Frequency slow-up

 

by 4 times without clearing of counter, an

(Up to command)

 

error P03is displayed.

e

* The cause is considered as excessively little

As command is

 

 

amount of refrigerant, defective PMV, or

 

 

clogging of cycle.

 

 

[°C]

 

 

a

b

c

d

e

 

 

 

 

 

 

SM560

117

112

108

105

98

 

 

 

 

 

 

SM800

111

106

100

95

90

 

 

 

 

 

 

3. Current release control

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

SM560

SM800

model

COOL

HEAT

COOL

HEAT

 

 

 

 

 

I1 value [A]

10.22

10.35

13.00

14.43

 

 

 

 

 

* For the cooling only models, only COOL is objective.

[A]

Frequency down

I1

Hold

 

10.5

Hold

Normal operation

 

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Toshiba RAV-SM560AT-E Requirement, 57, Pulse Modulating Valve PMV control, Discharge temperature release control