Hitachi RAS-(2-3)HVRN(S)(2), Service Manual

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11 Electrical checks of
main parts
447
SMGB0064 rev.0 - 08/2011
11
Protection function
Applicable model RAS-(2-3)HVRN(S)2 RAS-(4-6)HVRNS2E
RAS-(8/10)HRNSE
RAS-(4-6)HRNS2E
Protection of IPM
IPM has four protection function for self-protection.
1 Some of the output terminals between “U” and “V” “V” and “W” “W” and “U” has a short-
circuit.
2 Running current reaches the maximum rated current.
3 Abnormal temperature is measured by internal thermistor.
4 Control voltage decreases abnormally.
Overload control
Overload control as a current greater than (rated current X105%).
Overload control release at a current smaller than (rated current X 88%).
Fin temperature increase The unit is stopped when the fin temperature is higher than 80 ºC (1 Phase) 100 °C (3 Phase).
Earth detection The unit is stopped when the compressor is earthing.