Control Specification SiBE06-70846 Function and Control3.12 Malfunctions3.12.1 Sensor Malfunction DetectionSensor malfunction may occur either in the thermistor or current transformer (CT) system.Relating to Thermistor Malfunction1. Outdoor heat exchanger thermistor2. Discharge pipe thermistor3. Fin thermistor4. Outside air thermistor3.12.2 Detection of Overload and Over CurrentOutline In order to protect the inverter, detect an excessive output current, and for protectingcompressor, monitor the OL operation.Detail If the OL (compressor head) temperature exceeds 120~130°C (depending on themodel), the compressor gets interrupted. If the inverter current exceeds 22A (25/35 class) or 30A (50 class), the compressorgets interrupted too.3.12.3 Insufficient Gas ControlOutline There are three ways of control to detect insufficient gas.I Detecting by power consumptionIf the power consumption is below the specified value and the frequency is higher than the55 Hz (depending on the model), it is regarded as insufficient gas.The power consumption is weak comparing with that in the normal operation when gas isinsufficient, and gas insufficiency is detected by checking a power consumption.II Detecting by discharge pipe temperatureIf the discharge temperature is higher than the target discharge pipe temperature, and theelectronic expansion valve is fully open more than the specified time, it is regarded asinsufficient gas.III Detecting by the difference of temperatureIf the difference between inhale and exhale temperature is smaller than the specified value, it isregarded as insufficient gas.Refer to “Insufficient Gas” on page 129 for details.FrequencyPower consumption Insufficient gas zone55 Hz(R2834)Gas insufficientzone(R1391)
