APD Technical Series · 21/30 · ATS troubleshooting
Troubleshooting Industrial Automatic Transfer Switches
ATS problems are often sequence or coordination problems – not simply a failed mechanism.
The engineering point
Engineering decisions made early prevent expensive field problems later.
What you'll take away
Follow the sequence
Check source sensing, start signal, permissives, timing, transfer, and retransfer in order.
Verify inputs before parts
Confirm control power, voltage sensing, fuses, interlocks, and upstream conditions.
Test safely under controlled conditions
Document settings and reproduce the fault without creating an unnecessary outage.
Built for
- Industrial Maintenance
- Field Service
- Facilities
Go deeper
Automatic Transfer Switches: Types, Transitions and Application
An automatic transfer switch moves a load between a normal source and an alternate source, usually a generator, and the way it makes that move decides what the load experiences. This article covers ATS construction and ratings, the three transition types, bypass-isolation and service-entrance variants, and the timing and code context that govern application.
Read the engineering articleMore in the series
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