Overcurrent of Inverter Compressor
1. Meaning of Alarm
- Secondary current effective value detected the overcurrent (trip current value).
- Single-phase model: Trip current = 24.0 A
- 3-phase model: Trip current = 18.0 A
- Secondary current instantly detected over xx A.
- Single-phase model: xx A = 45.0 A
- 3-phase model : xx A = 36.0 A
2. Check of content
|0 Multiple factors||0-1||Replaced the compressor (added oil, if it was necessary) but it occurred again immediately.||Yes||7-1|
|0-2||Replaced the board, but it occurred again immediately.||Yes||Replace compressor along with adding oil, then recheck from|
Power cord connections are loose.
Correct the wiring
|1-2||Rated power voltage is not within + 10%.||Yes||Test the power supply|
Extreme fluctuations in voltage.
|Yes||Test the power supply|
|1-4||An open phase state is observed.||Yes||Test the power supply|
|2-1||Disconnected parts, miswiring and/or poor connections (loose) are observed in the connections on the CR board and/or in the connections of components that are connected by wiring from the CR board.||Yes||Correct|
|2-2||Disconnected parts, miswiring and/or poor connections (loose) are observed in the connections of outdoor board(s) that are connected by wiring from the CR board.||Yes||Correct|
|2-3||Disconnected parts, miswiring and/or poor connections (loose) are observed in the connections of outdoor board(s) that are connected by wiring from the HIC board.||Yes||Correct|
Disconnected parts, miswiring and/or poor connections (loose) are observed in the connections of HIC boards connected by wiring from the CR board.
Disconnected parts, miswiring and/or poor connections (loose) are observed in the connections of HIC board(s) that are connected by wiring from the outdoor board.
|2-6||Disconnected parts, miswiring and/or poor connections (loose) are observed in the connections of HIC board(s) that are connected by wiring to a compressor.||Yes||Correct|
|3 Compressor wiring||3-1||Disconnections and/or miswiring are observed in the connecting location of the compressor terminals.||Yes||Correct|
|3-2||Conditions such as burned terminal covers and/or discolored terminals are observed in the connecting location of the compressor terminals.||Yes||Eliminate looseness by changing the termi-nals, or crimping the terminals again.|
Check the situation
|4-1||Outdoor air intake temperature is high.||Yes||Take measures|
|4-2||May be caused by poor outdoor unit air flow (dirty or clogged heat exchanger, blocked discharge port, etc.)||Yes||Correct|
|4-3||Air short circuit has occurred. This is a phenomenon when discharged air (exhaust heat) from the outdoor unit is drawn back into the suction vent.||Yes||Prevent air short circuit|
|4-4||Indoor air intake temperature is high.||Yes||Take measures|
|4-5||The filter of the indoor unit is clogged.||Yes||Clean the filter|
|4-6||Air short circuit has occurred. This is a phenomenon when discharged air (exhaust heat) from the indoor unit is drawn back into the suction vent.||Yes||Prevent air short circuit|
|5 Check operation||5-||Possible to operate.||Yes||5-2|
|5-2||Operating pressure is affected by pressure overload.||Yes||5-3|
|5-3||Tends to have an overcharge of refrigerant in the system.||Yes||Adjust the amount of refrigerant|
|5-4||Tends to operate for a long time turning gas back into liquid.||Yes||Check the operation of functional parts|
|5-5||Tends to have insufficient refrigerant charge in the system.||Yes||Adjust the amount of refrigerant|
|5-6||Even though the high pressure saturation temperature is 43°C or less, the secondary current of the inverter is high. (The frequency (Hz) ends up dropping due to the current.)||Yes||Replace the compressor|
|No||See what happens.|
|6-1||Dividing the outdoor EEPROM INV operation time by the number of times oil was supplied to the system yields 3 hours or less.||Yes||6-2|
|6-2||There is a history of H31 in the pre-trip counter of the outdoor EEPROM alarm history.||Yes||Replace the oil. How-ever if 6-1 was "no," it is not necessary to add oil.|
Check the HIC boards
|7-1||The results of HIC board IPM Pass/Fail Tests show the outside the range of the resistance of a conforming part listed in the next page.||Yes||Replace HIC board|
|8 Check the compressor||8-1||The compressor is causing a failure in the insulation.||Yes||
Replace the compressor
|8-2||The winding resistance of the compressor is abnormal.
||Yes||Replace the compressor|
|9 Check the HIC PC boards||9-1||Replace the HIC PC board and operate the unit. (Apply putty and screws must not be loose) Does it operate normally?||Yes||See what happens.|
Check the outdoor unit mainPC board
|10-1||Replace the control PC board and operate the unit.|
- (Check content of 7) The test check of the HIC board is only a check on the output level, so the input stage may not be working.
- With the filter board broken, alarm P16 may not be triggered.
• HIC board IPM Pass/Fail Tests
- Measure with an analog tester. (Set to the k ohm range.)
- Measure the board by itself. (Remove wires connected from other parts.)
- Measure using IPM terminals.
✭ Conforming part resistance value (measure with an analog tester)
|Resistance value (ohm)||1 k to 5 k||1 k to 5 k||1 k to 5 k||5 k to 10 k||100 k to ∞||100 k to ∞||100 k to ∞||100 k to ∞|
|Resistance value (ohm)||100 k to ∞||100 k to ∞||100 k to ∞||1 k to 5 k||1 k to 5 k||1 k to 5 k|
Excepting the parts of “100 k to ∞“, it is acceptable if a small resistance value appears as a reference value unless the value is “0 = short-circuit”.