Below is a guide to help you to establish the cause of a fault.
It follows the PACE principle and looks in-turn at

• Product
• Application
• Configuration
• Environment

In order to establish the reason for the fault or problem that you have

Environment

Question

Is the product working outside of its environmental specification? E.g. Temperature, humidity, mounting recommendations, etc.

Is it wired to the circuit design?

Have you checked the connections? E.g. terminals to correct torque, ferrules fitted correctly etc.

Has any other part of the system failed?

Has this application worked previously?

Is the communication or network to other devices working correctly?

Are the signals from other devices or systems healthy?

Is the safety circuit healthy?

Are the connected devices Schneider parts? E.g. cables, memory cards, software etc.

Application

Question

Is it being used outside of it’s specified parameters? Eg number or frequency of operations, current limitations etc

What was happening when it failed?

Is the fault repeatable?

Can you substitute a known working product, and does the fault remain? Note! only change one item at a time and retest in-between.

Can you test the product with a simplified function or application?

Have you found a workaround for the fault?

Can you operate the product on its own?

Could there be a problem with mechanical, hardwired or software interlocks?

If you are not the system designer, have you consulted them about the issue?

Configuration

Question

Are the parameters correct?

Is the software configuration correct?

Is the programmed function being used correctly?

Is the communication configuration correct?

Is there conflict between devices? Eg duplicated IP or network addresses

Has the device error handling been implemented?

Have you got the correct PC operating system, configuration and programming software, firmware revision and device drivers?

Product

Question

Did the device work before and has stopped working?

Is the product working in line with Schneider published documentation?

Are there any physical signs of product damage?

Have you any other failures of the same product?

Is it an intermittent fault? Can you find a pattern to reproduce the fault?

Are there any physical clues to fault such as noise, smell, heat, discolouration etc.

Released for:Schneider Electric UK