Hitachi RAS-(3-6)HVNC1(E) - Page 469

11 Electrical checks of
main parts
455
SMGB0087 rev.0 - 12/2013
11
Protection function
Applicable
model
RAS-(4-6)HNP1E RAS-(4-6)HNC1E RAS-(8-12)HN(P/C)(E)
RAS-(2-2.5)HVNP1
RAS-3HVNC1
RAS-3HVNP1E RAS-(4-6)HVNP1E RAS-(4-6)HVNC1E
Excessive high
or low voltage
for inverter
Excessive low voltage at a voltage is lower than
350 V DC
Excessive high voltage at a voltage is higher
than 750 V DC
Excessive low voltage at a voltage is lower than 194 V DC
Excessive high voltage at a voltage is higher than 400 V DC
Abnormality of
current sensor
(0A detection)
Stoppage at a current of compressor smaller
than 1.5A.
When the frequency is 15 to 18Hz after starting.
Cause of abnormality:
Failure of current sensor
Failure of IPM/DIP-IPM/ ISPM
Failure of compressor / fan motor
Disconnected wiring
(1) When the compressor’s operating frequency
reaches 15 to 18 Hz after the compressor starts, the
effective value of running current at each phase is
1.5A or less.
(2) The wave height value of running current for the
phase positioning is 5A or less before the compressor
starts (at the end of the phase positioning).
Cause of Abnormality: Failure of Current Sensor (on
Inverter PCB),
Failure of IPM, Failure of Compressor, Disconnected
Wiring
Overcurrent
protection for
inverter
Time
Detecting current is more than
150% of the rated current.
Rated
current
x 150%
Rated
current
x 105%
Detecting current is more than
150% of the rated current
Rated current x
150%
Rated current x
105%
1 Short-circuit trip of arm *)
2 Instantaneous overcurrent trip *)
3 Instantaneous overcurrent trip: it is detected when current valve is over rated current x 150%.
4 Electronic thermal trip: it is detected when current valve rated current x 105% for over 30 seconds or for over 3
minutes in total within 10 minutes.
N O T E
*) Internal protection IPM
Condition is maintained longer than 30 seconds or accumulated longer than 3 minutes during 10 minutes sampling time.
Protection
of transistor
module
IPM has four protection function for self-protection.
1 Short circuit in any of the “U”, “V” or “W” terminals
2 Running current reaches the maximum rated current.
3 Abnormal temperature is measured by internal thermistor (for 8 to 12HP).
4 Control voltage decreases abnormally.
Overload con-
trol
Overload control as a current greater than (rated current X105%).
Overload control release at a current smaller than (rated current X 88%).
Fin tempera-
ture increase
The unit is stopped when the n temperature is higher than 80ºC (for 3HP), 90ºC (for 4 to 6HP Premium), 90ºC (for
4 to 6HP Standard) or 100ºC (for 8 to 12HP).
Earth detection The unit is stopped when the compressor is earthing.