Question

(TCO 2) A 120 VAC, 10 A electric heater needs to be connected to a 120 V, 2 A PLC output module. What will happen if the heater is directly connected to the module

Answer 1

Answer:

When a 10A electric heater is directly connected to 2A PLC output module for switching then PLC output module will most probably be damaged due to excess current drawn by the electric heater.

Explanation:

Usually, the high current rating loads such as electric heater are connected to the PLC via relays or contactors. A relay or contactor is a device which is used to make or break the electrical circuit.

These relays are capable of handling heavy currents and perform reliable switching. Contactor is preferred when the current is more than 10 A and relay is preferred when current is less than or equal 10 A.