A bulb (incandescent lamp) is used as a DC load. A thermistor is connected in series to absorb the surge
current which occurs when the load is ON.
⑦
A bulb (neon lamp) is used as an AC load. A thermistor is connected in series to absorb the surge current which
occurs when the load is ON.
Mutually exclusive output: For example, Y0.4 controls the clockwise rotation of the motor, and Y0.5 controls the
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counterclockwise rotation of the motor. The interlock circuit which is formed, and the program in the PLC
ensure that there are protective measures if an abnormal condition occurs.
Transistor Output Circuit
The AH series transistor outputs are equipped with the diodes which provide the counter-electromotive force protection.
They can be used if they are not turned ON/OFF frequently and there are low-power inductive loads. If they are turned
ON/OFF frequently and there are high-power inductive loads, they must be connected to noise suppression circuits to
reduce the noise and prevent the overvoltage or the overheating from damaging the transistor output circuit.
NPN/PNP transistor output circuit
①
Direct-current power supply
②
Emergency stop
③
Fuse
Ch a pt er 4 Ins t al l at i o n an d W ir in g
V DC power supply
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