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Is UL 508A Certification possible with a NON UL part?

Is UL 508A Certification possible with a NON UL part?

Is UL 508A Certification possible with a NON UL part?


My shop is going to proceed with UL 508A training soon. We use Yokogawa Data Recorders which are CSA certified but they are NOT UL certified. They are 24 VDC devices.

Can I include it in my panel and certify that it meets UL 508A specs?

I have heard that UL 508A is possible as long as you label it inside the panel.

Thanks for your input.


RE: Is UL 508A Certification possible with a NON UL part?

Maybe maybe not. As part of getting your panel shop UL508 certified, you will need to submit a sample production unit. UL will inspect it and most likely come back with pages of comments to be corrected. Usually they are lenient on 24 VDC equipment, but some inspectors are tougher than others.

RE: Is UL 508A Certification possible with a NON UL part?

See "Increased Component Sourcing" in this link. Perhaps your device will qualify. I'm sure you can ask your question when undergoing the training.

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RE: Is UL 508A Certification possible with a NON UL part?

Anytime there is money involved - I don't recommending guessing. Buy a copy of UL 508A
It is $700 or so - but you need one.


The information contained in Appendix B is not part of this American National Standard (ANS) and
has not been processed in accordance with ANSI’s requirements for an ANS. As such,
Appendix B may contain material that has not been subjected to public review or a consensus
process. In addition, it does
not contain requirements necessary to fulfill the objectives of the standard.

B.1.3 Components able to be covered under the requirements of this supplement include
a switching device, relay, meter, recording device, or similar component that controls loads or
other devices within the control circuit of an industrial control panel and do not include
connections to external devices other than
as specified in B.2.4.

Harmless flakes working together can unleash an avalanche of destruction

RE: Is UL 508A Certification possible with a NON UL part?

Can you expand on what "you label it inside the panel" means? That sounds like a wrong answer.

There are a few ways it could be found acceptable.

#1. If you build the package with the 24V following the limited energy source rules or using a class 2 power supply then the recorder doesn't have to be listed at all.

#2. As part of the UL508A documentation you should get a document called Follow-up and Inspection Instructions. This contains a table called "Component Usage Instructions for CSA Components Certified to US Requirements". If the recorder is in that table and accepted then it can be used.

#3. If you cUL list the control panel and specify that it is for use in Canada only then the recorder would be accepted by the UL508A inspector.

#4. Follow Appendix B in the standard. These rules basically limit the energy and shock hazard of any power sources connected to the component so that the component won't fatally shock someone or cause a fire.

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