Questions tagged [ul]

UL (Underwriters Laboratories) is a global independent company that performs safety consulting and certification. They publish many safety standards for electrical and electronic products and the UL mark on equipment indicates it has passed their tests for electrical safety.

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UL certification and laser tag equipment

We are a 32+-year-old laser tag equipment company. We purchase parts overseas and assemble them in the US and have hundreds of installations all over the world. We have been told by 1 location that ...
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Do power strips need to have a breaker?

In North America we commonly use power strips to connect equipment to the building. https://en.wikipedia.org/wiki/Power_strip I noticed that some power strips have a circuit breaker, and some do not. ...
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What are the differences between UL1581 and UL2556 for VW-1 (Vertical Flame Test)?

In IEC62368-1, it's stated: Wire complying with UL 2556 VW-1 is considered to comply with these requirements. I've asked a manufacturer if he could meet these requirements and he answered that he ...
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IEC grounding and bonding standard

Is there an equivalent standard in IEC such as UL 467 or IEEE 837 which talks about the various test procedure for bonding clamps? Is IEC 61914:2015 similar to UL 467?
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How do I determine battery manufacturers/companies whose batteries that have met UL 1642 certification?

How do I determine battery manufacturers/companies whose batteries that have met UL 1642 certification? I am asking because I want to determine other companies whose products have successfully ...
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Where do hi-pot multipliers come from?

I am researching AC vs. DC hi-pot testing. According to UL 508 and IEEE 421.3, a hi-pot test should, among other things, subject the unit under test to 1000 volts plus twice the rated voltage of the ...
Bort's user avatar
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Need advice on new device regulatory requirements

I have designed a product (device) that runs on 12 VDC (similar to a laptop). It is AC powered using a (table top), detachable switching power supply 100 VAC to 240 VAC, 50-60 Hz, again exactly like a ...
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UL listing of a fan

An electrical Inspector has stated he cannot accept our fan for use in an industrial diesel Exhaust removal system since the entire fan does not show a UL listing number. We have tried to explain that ...
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Which UL standard(s) holds the specifications of all UL AWM styles of cabling?

Which UL standard documents the specifications of all UL AWM styles of cabling, detailing their construction, conductor sizes, insulation, etc. ? In my research, I was directed to UL Standard 758 ...
mach128x's user avatar
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UL certification requirements

I'm designing a circuit board for a large industrial product which is intended to be UL certified, so the boss wants as many individual submodules to be UL certified as possible, including mine. The ...
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Is there a double standard or has something changed with NRTL and CSA requirements?

I've been going over threads about having NRTL or CSA certified electrical equipment. Everyone comments the seriousness of this. But I am confused that Home Depot, Harbor Freight, Target, on and on ...
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Does anyone know the UL standard related to resistors and isolation on AC mains?

I have a circuit that is attempting to measure AC line voltage 120-240V but I was told by the certification test lab that my voltage divider resistors would require an expensive 3 week soak test. The ...
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Reference material for mains-interfacing circuit safety

I've designed a simple switch/timer circuit for the following environment: Residential installation for North America (technically only for Canada) Single-phase 120Vac Current of switched output ...
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