Hitachi EV-1.5N1, Service Manual

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8. Troubleshooting
275
SMGB0079 rev.0 - 01/2013
8
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Activating condition of protection control code
To monitor the conditions such as the temperature change and others, the control of the frequency and other controls are
performed by the protection control in order to prevent the abnormal operations. The activating conditions of protection
control are shown in the table below:
RAS-(2-2.5)HVNP / RAS-3HVNC
Code Protection Control Activating Condition Remarks
P0
Low-Pressure Ratio Control at Cooling
Operation
If Compression Ratio ε exceeds a threshold value
=> Frequency Increase
—
P1
High-Pressure Ratio Control at Heating
Operation
If Compression Ratio ε is lower than a threshold value
=> Frequency Decrease
—
P2 High-Pressure Increase Protection
High Pressure Switch for Control is activated
=> Frequency Decrease
—
P3 Over Current Protection
Inverter Output Current > (*1)A
=> Frequency Decrease
—
P4 Inverter Temperature Increase Protection
Inverter Fin Temperature
RAS-(2-2.5)HVNP / RAS-3HVNC ≥ 70 ºC
=> Frequency Decrease
—
P5
Discharge Gas Temperature Increase
Protection
Temperature at the top of compressor is high
=> Frequency Decrease
—
P9
Unbalance Power Source Detecting
Inverter Output Current exceeds a threshold value
=> Frequency Decrease
—
PA Current Demand Control
Inverter Output Current exceeds a threshold value
=> Frequency Decrease In case of
Demand Control Setting
Pb Low-Pressure Decrease Protection
Low Pressure Switch for Control is activated.
=> Frequency Decrease
—
(1*)
Connection 220-240V
HP 2 2.5 3
Current (A) 8.0 8.0 10.5