Hitachi Set Free mini-HNRQ1 Series, Service Manual

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142
MAINTENANCE
(a) Level of Detection
When the output current exceeds the rated current continuously for 10 seconds, an abnormality is
detected.
(b) Function
When output current exceeds the rated current, and the frequency decreases. An overload signal is
issued when output current exceeds the rated current continuously for 10 seconds. When the output
current decreases lower than 98% of the rated current, the frequency decrescence is canceled.
(c) Cancellation of Protection Function
After the operation described in the above item (b) is performed, this control is canceled.
(2) 7~12HP
●
Specification
Applicable Model 7-8HP 10-12HP
Model of Inverter PCB DRV-180A-A DRV-180B-A
Applicable Power Source 380-415V ±10% /3Ph/50Hz
Output Current (Maximum) (A) (RMS) 24 30
Range Output Frequency (rps) 15~140 10~130
● Protective Function
(i) Excessive High or Low Voltage for Inverter
(a) Level of Detection
When the voltage of direct current is greater than 752V, an abnormality is detected.
When the voltage of direct current is smaller than 396V, an abnormality is detected.
(b) Function
When an abnormality is detected, the inverter compressor is stopped and the cause code of inverter
stoppage is communicated to outdoor unit PCB.
(c) Cancellation of Protection Function
When the wired controller is off or main power supply is cut off.
(ii) Overcurrent Protection for Inverter
(a) Level of Detection
When the current detected is more than 49.5A (DRV-180A-A);
When the current detected is more than 69.3A (DRV-180B-A)
(b) Function
When an abnormality is detected, the inverter compressor is stopped and the cause code of inverter
stoppage is communicated to main control.
(c) Cancellation of Protection Function
When the wired controller is off or main power supply is cut off.
(iii) Protection of IPM of Inverter
(a) Level of Detection
When some of the output terminals between “U” and “V”, “V” and “W”, “W” and “U” of IPM of inverter
PCB are short-circuited, an abnormality is detected.
When the control voltage of IPM of inverter PCB abnormally decreases, an abnormality is detected.
(b) Function
When an abnormality is detected, the inverter compressor is stopped and the cause code of inverter
stoppage is communicated to outdoor unit PCB.