PURPOSE: To obtain a highly reliable air conditioner excellent in serviceability by determining the type of an operated protector based on a detection signal from a protective operation detecting means and presenting the determined type on a display along with a defective input from the protective operation detecting means.
CONSTITUTION: Protective operation detecting means 46, 47 are connected in series with each contact of a protector and in parallel with holding contacts 16b, 17b, time limit contacts 44a, 45a and electromagnetic contactors 16, 17 in order to detect whether the protector is operating or not. A microcomputer 13 receives detection signals from the means 46, 47 through an input circuit 42, and a CPU 40 determines the type of the operated protector and delivers a signal through an output circuit 38 to a display means 19 comprising current limiting resistors 24-29 and LEDs 31-36 thus displaying the type of the operated protector. Furthermore, the CPU 40 detects imperfect connection between the means 46, 47 and the circuit 42 based on the state of the contacts 14a, 15a and the detection signals from the means 46, 47 and delivers a signal to the current limiting resistor 30 in the display means 19 and LED 37.
NAKAMURA SETSU
IGARASHI YOSHINOBU
KURACHI MITSUNORI
TANI SHUICHI
ISHIKAWA KOJI
TAGASHIRA HIDEAKI
