PLC output Protection

"Prevention is Better than cure"

In automation industry there are some reasons why our equipment get damage or malfunction, but if we know these reasons we can come up with the solution to prevent the damage that may occur, engineers are one of the intelligent people here in the world, they can fix the damage but if we can put some protective equipment and preventive method, We can reduce the production downtime.

Causes of PLC Output Damage

• Wrong wire termination
• Over Current
• Stored Energy

Wrong Termination

Cause

• Human Error
• Wrong Circuit Diagram

Solutions

• Supervisor / Engineer must check and approved the diagram before project execution
• Loop checking
• Yellow Tagging

Over Current

Cause

• Defective Equipment / Field devices
• Short Circuit

Solutions

• Preventive Maintenance
• Install fuse for short circuit protection

Stored Energy

Cause

• Inductive Loads

Solutions

• Install Diode (reverse bias) in parallel with the load

Related Article

• Protect your instrument from stored energy cause by inductive load

Reference Video

• Tips in PLC output Protection