Relay Output in PLC?

Relay Output in PLC?

Relay outputs are extensively employed in the manufacturing industry to control the activation and deactivation of slow-switching devices, such as motors, valves, and pumps. Since relay switching is mechanically based, its response time is slower compared to transistor outputs.

The lifespan of a relay output contact in a PLC depends on the load connected to it.

The presence of load-generated reverse electromotive force or rush current may lead to poor contact and potentially reduce the relay’s lifespan. he types of loads that can be connected to a relay include…

1.Inductive Load

2.Capacitive Load

3.Lamp Load

4.Resistance Load

Wiring for Relay Type Output: With relay-type outputs, you can directly connect both AC and DC loads, as illustrated in the image below.

How to Wire Relay Output?

AC Load and DC Load to PLC Relay Output

Response time of Relay output is slow compared to Transistor Output So Application where fast switching is required relay output is not used.

Wiring Relay Output with a DC Load and a Common Negative 24-Volt Connection.