Article 411 question

[sparrott4]

I'm confused about the UL listings required to comply with article 411. Article 411 states that system components must be listed. But in Mike Holt's low voltage book he states that no UL listing exists that complies with 411. He mentions that UL 2108 is being developed (6 years and waiting!) that will comply.

Doesn't UL 1838 comply with 411? If not, why not – is it the 30V vs. the 15V issue?

I think theres a common belief that in order to comply with NEC code, transformers must be 15V or less. Is that correct?

[petersonra]

As I understand it, at one time UL did not list anything under 30V. As time passed, they have started to list stuff because of the demand from certain (mostly regulatory) bodies that items be listed.

[sparrott4]

Mike, any further word on this topic?

[mhulbert]

Sparrot,
I'm not sure about UL 2108, however I have used and specified Q-Tran units before, they are listed to standard 5F78, and their UL sticker says they are in compliance with 411. Scroll down this spec sheet to see the UL sticker:
http://www.q-tran.com/pdf/q6s.pdf

The other company that makes listed units is Semper Fi Power supply.

All listed units have primary and secondary protection. Secondary cannot exceed 25A.

[dillon3c]

Originally posted by sparrott4:
But in Mike Holt's low voltage book he states that no UL listing exists that complies with 411. sparrott4,

What addition of "Mike Holts Low Voltage Book" are you looking at?

I have Holt's new text titled: Understanding Low-Voltage and Power-Limited Systems.

*And that statement, would be missing from my text..

Edited: must be two differant additions..

[ September 09, 2005, 06:33 PM: Message edited by: dillon3c ]