SUPER DIGITAL
SUPER DIGITAL
SUPER DIGITAL
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9-2. Outline of Main Controls<br />
<br />
1. PMV (Pulse Motor Valve) control<br />
1) PMV is controlled between 30 and 500 pulsed during operation.<br />
2) In cooling operation, PMV is usually controlled with the temperature difference between TS sensor and<br />
TC sensor aiming 1 to 4K as the target value.<br />
3) In heating operation, PMV is usually controlled with the temperature difference between TS sensor and<br />
TE sensor aiming –1 to 4K as the target value.<br />
4) When the cycle excessively heated in both cooling and heating operation, PMV is controlled by TD<br />
sensor. The target value is usually 91°C in cooling operation and 96°C in heating operation.<br />
REQUIREMENT<br />
A sensor trouble may cause a liquid back-flow or abnormal overheat resulting in excessive shortening of the<br />
compressor life. In a case of trouble on the compressor, be sure to check there is no error in the resistance<br />
value or the refrigerating cycle of each sensor after repair and then start the operation.<br />
2. Discharge temperature release control<br />
1) When the discharge temperature did not fall or the discharge temperature rapidly went up by PMV<br />
control, this control lowers the operation frequency. It subdivides the frequency control up to 0.6Hz to<br />
stabilize the cycle.<br />
2) When the discharge temperature detected an abnormal stop zone, the compressor stops and then<br />
restarts after 2 minutes 30 seconds.<br />
The error counting is cleared when the operation continued for 10 minutes. If the error is detected by<br />
4 times without clearing, the error is determined and restarting is not performed.<br />
∗ The cause is considered as excessively little amount of refrigerant, PMV error or clogging of the cycle.<br />
3) For displayed contents of error, confirm on the check code list.<br />
TD [˚C]<br />
111<br />
109<br />
106<br />
103<br />
96<br />
Abnormal stop<br />
Frequency normal down<br />
Frequency slow down<br />
Frequency hold<br />
Frequency slow up<br />
(Up to command)<br />
As command is<br />
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