| 摘要 |
PURPOSE:To prevent breakage of circuit due to throwing electric source under mis-wiring by a method wherein a comparator, generating an output when the D.C. impedance of a signal cable connected to the thermistor of an outdoor unit is reduced to a value lower than a reference value, is provided in the device. CONSTITUTION:When a program is started, the conditions of all input ports are read in a step S1. Existence of mis-wiring is decided in the step S2. In case cables 12a, 12b for signal are connected instead of the cables 5a-5e for electric source, a mis-connection detecting signal is outputted from the comparator 18 to supply it to a micro-computer 20 since the D.C. impedances of a motor 6 for driving compressor and a motor fan 9 are sufficiently lower than the same of the thermistor 10. In case the decision of step S2 is 'no', the step is shifted to the step S3 and normal control of air-conditioning is carried out. In case the decision in the step S2 is 'yes', the step is shifted to the step S4 and the mis-wiring is alarmed. |
