SHARP AE-X075E
Service Manual

AH-X075E/X095E AU-X075E/X095E AY-X075E/X095E AE-X075E/X095E

2-3 Overcurrent protection (1) Compressor lock detection If the set value (3.0 A) of AC current is exceeded at 19 to 23 Hz when operation begins, operation is stopped. In this case, the compressor outdoor fan does not stop, and 170 seconds after operation is stopped, another try will be made. Three retries are allowed. On the fourth retry, a complete stop request signal is sent to the indoor unit, and the outdoor unit will remain stopped until reset is performed. At this time, the 3-minute delay for control of the outdoor unit will not function; therefore, do not cancel by removing the plug and cutting the power. (2) DC overcurrent detection, AC overcurrent detection To protect against overcurrent due to sudden changes in load, the compressor is stopped if the set value 30 A DC is exceeded in the DC section, or the set value 8.5 A AC is exceeded in the AC section. In this case, the outdoor fan does not stop, and 170 seconds after operation is stopped, another try will be made. Three retries are allowed. On the fourth retry, a complete stop request signal is sent to the indoor unit, and the outdoor unit will remain stopped until reset is performed. At this time, the 3-minute delay for control of the outdoor unit will not function; therefore, do not cancel by removing the plug and cutting the power. 2-4 Compressor protector control If the temperature of the compressor chamber exceeds 114°C, the compressor is stopped. In this case, the outdoor fan does not stop, and when the compressor chamber temperature decreases to 100°C three minutes after operation is stopped, another try will be made. Three retries are allowed. On the fourth retry, a complete stop request signal is sent to the indoor unit, and the outdoor unit will remain stopped until reset is performed. At this time, the 3-minute delay for control of the outdoor unit will not function; therefore, do not cancel by removing the plug and cutting the power. 2-5 Power transistor module protector If the temperature of the chips in the power transistor module exceeds 105 °C, the compressor is stopped. In this case, the outdoor fan does not stop, and when the temperature of the chips in the power transistor module decreases to 105 °C 170 seconds seconds after operation is stopped, another try will be made. Three retries are allowed. On the fourth retry, a complete stop request signal is sent to the indoor unit, and the outdoor unit will remain stopped until reset is performed. At this time, the 3-minute delay for control of the outdoor unit will not function; therefore, do not cancel by removing the plug and cutting the power. 2-6 Power factor module If a voltage error (over 400 V), current error (over 17 A), or temperature error (over 90°C) is detected in the power factor module, 170 seconds the compressor is stopped. In this case, the outdoor fan does not stop, and 170 seconds after operation is stopped, another try will be made. Three retries are allowed. On the fourth retry, a complete stop request signal is sent to the indoor unit, and the outdoor unit will remain stopped until reset is performed. At this time, the 3minute delay for control of the outdoor unit will not function; therefore, do not cancel by removing the plug and cutting the power. 2-7 Serial signals (1) Serial signals consist of all 96-bit signals. (2) If the outdoor unit does not receive a serial signal, it will stop approximately 30 seconds later. Note that this is true only of normal operation; in test mode, it does not stop and operation takes place based on the test mode commands. 2-8 Four-way rotary valve The four-way rotary valve will not switch when there is a large difference in refrigerant pressure. To make the four-way rotary valve switch normally, switching is delayed by approximately 3 minutes and the refrigerant pressure difference is decreased first. Also, the temperature of the indoor heat exchanger at the time of compressor activation and the temperature 150 minutes after activation are compared, and it is determined whether or not they are suitable for the operating mode at that time. If they are not suitable, a four-way rotary valve error results and the compressor is stopped.

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