Two switches parallel operation

Application:-Make operation in two different control panels so the operator can operate one lamp from two different control rooms. One panel is in the control room 1 and the second panel is in control room 2. The lamp can be operated from two different switches. Explain using and electrical drawing and write PLC program for application.

Components:-Programmable logic controller, Electrical panels, wires, 24VDC switches with NO contacts, 24VDC indication lamp, 24 VDC relay.

Diagram:-Electrical wiring diagram of two switches parallel operation.

Explanation:-

As per our application, we can use the above OR gate for parallel operation. In the application, we are using two switches and one lamp for indication. If panel switch 1 or Panel switch 2 pressed, an indication lamp should be ON. So in the above electrical wiring diagram, we have used panel switch 1 and panel switch 2 in parallel connection so electrical supply can flow either from panel switch 1or Panel switch 2.

PLC program:-

Write the ladder program for parallel operation using ladder diagram language. Here for ladder logic, we can use any PLC system. For PLC logic we need digital inputs and outputs.

For our application, all switches are digital inputs and lamp is a digital output. To define digital input address and output address as per below explanation,

 Digital inputs:-

Panel 1 switch=I0.0

Panel 2 switch=I0.1

Digital Output:-

Lamp=Q0.0

Memory coil:-

Memory bit-M0.0

PLC program Explanation:-

In-network 1 we have considered two digital inputs for two panel 1 switch (I0.0) and panel 2 switch (I0.1). So we have taken NO contact of panel 1 switch (I0.0) in parallel with panel 2 switch (I0.1) for parallel operation. So when panel 1 switch or panel 2 switch ON, memory bit (M0.0) will be ON.

In-network 2 we have taken NO contact of memory bit (M0.0) to operate lamp (Q0.0).