WHY? (From most likely to least.)
#1 Factor: Environment
#2 Factor: Brand/Model
#3 Factor: Electrical Design supporting PLC
#4 Factor: PLC Management

WHAT? (From most likely to least.)

• PLC output modules
• PLC input modules
• PLC communication modules
• PLC power supply
• PLC processor module

All Equipment Failure (physics)

1. Mechanical devices are more likely to fail than electrical,
2. Electro-mechanical devices are more likely to fail then solid-state devices,
3. High current devices are more likely to fail than low current devices.

To read details about the above, see ...

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This article answers the question... What are PLC controller failure rates? It also covers equipment failure rate from a PLC failure rate perspective (automation controller).

What's your war story?

1. Factor: Environment
2. Factor: Brand/Model
3. Factor: Electrical Design supporting PLC
4. Factor: #-Link-Snipped-#

1. Factor: Environment
2. Factor: Brand/Model
3. Factor: Electrical Design supporting PLC
4. Factor: #-Link-Snipped-#