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Author Topic: brain storm an optimal human safety system for back line  (Read 97840 times)

John Roberts {JR}

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Re: brain storm an optimal human safety system for back line
« Reply #510 on: June 09, 2016, 09:47:17 am »

The U is for Underwriters, an insurance term.  I never quite thought of the connection until you made this post so I went and read the history of UL and I didn't see any ties to the insurance industry.

A curiosity.
Worked for fire insurance industry to test electrical devices, insulation flammability, etc.
http://www.ul.com/aboutul/history/
History according to them.

JR
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Frank DeWitt

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Re: brain storm an optimal human safety system for back line
« Reply #511 on: June 09, 2016, 10:50:18 am »

Underwriters Laboratories Inc. was founded in 1894 by William Henry Merrill. Early in his career as an electrical engineer in Boston, a 25-year-old Merrill was sent to investigate the World Fairís Palace of Electricity. Upon seeing a growing potential in his field, Merrill stayed in Chicago to found Underwriters Laboratories.
https://en.wikipedia.org/wiki/UL_%28safety_organization%29

Now it all makes sense.
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Mark Cadwallader

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Re: brain storm an optimal human safety system for back line
« Reply #512 on: June 09, 2016, 01:34:42 pm »

When you remember that the NFPA (National Fire Protection Association), the author of the NEC, is an organization created by the causualty insurance (fire insurance) industry, it makes even more sense.
« Last Edit: June 23, 2016, 03:03:18 pm by Mark Cadwallader »
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John Roberts {JR}

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Re: brain storm an optimal human safety system for back line
« Reply #513 on: June 23, 2016, 02:39:43 pm »

Is anybody familiar with this guy...? Hubbell 5200

I'd buy one to take apart but they're like $65  ??? ???

Looks like an LED version of the 3 lamp tester.

JR
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Tom Roche

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Re: brain storm an optimal human safety system for back line
« Reply #514 on: June 23, 2016, 02:52:11 pm »

Is anybody familiar with this guy...? Hubbell 5200

I'd buy one to take apart but they're like $65  ??? ???

Looks like an LED version of the 3 lamp tester.

JR

Probably nothing you didn't find already, but there's this: http://ecatalog.hubbell-wiring.com/press/catalog/Z-3.pdf
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Stephen Kirby

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Re: brain storm an optimal human safety system for back line
« Reply #515 on: June 23, 2016, 04:32:36 pm »

When I moved back to CA in 1980 I interviewed at UL.  They showed me around their "lab".  Aside from a flame tunnel most of the set ups were pretty cobby.  They had a bunch of electric weedwackers sitting on a wooden bench with zip-ties around the triggers and clamps they'd fabricated locking the rotors.  I asked how long they left them like that and was told something like 12 hours.  I figured anyone who held the trigger of a weedwhacker that wasn't doing anything for 12 hours might not be worth protecting.  There was another portable stair thing like you see at Home Depot with a bowling ball hanging from a rope tied to the top.  They'd epoxied an eye bolt in one of the finger holes.  There were laundry marker stripes on one of the hand rails and masonite attached to the front.  They would set a CRT (TV or computer monitor) on a table, pull the bowling ball back to one of the marks they had, let go and jump behind the masonite.  Pretty much everything there was like that.  They were really big on advanced degrees for their staff so that there was some weight behind their findings and reports.  Having dealt with various certification labs over the years since I've been similarly unimpressed.
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John Roberts {JR}

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Re: brain storm an optimal human safety system for back line
« Reply #516 on: June 23, 2016, 09:26:42 pm »

The value in UL approval is not that they are smarter engineers than me... it's that it will keep the lawyers in check.

JR
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Stephen Kirby

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Re: brain storm an optimal human safety system for back line
« Reply #517 on: June 24, 2016, 05:59:15 pm »

The value in UL approval is not that they are smarter engineers than me... it's that it will keep the lawyers in check.

JR
Understood.  That was why they needed everyone on the staff to have a PhD.  So the lawyers could impress juries.

Probably best if you can get Klein or GC interested in it.  Or at least distributing it in volume.  Most of the large contract manufacturers have pretty serious compliance labs.  And will do the testing for a volume order.  I'm flying out tonight to China and Quanta.  They have compliance labs on each of their manufacturing campuses.  Wouldn't carry as much weight with a US jury as UL but would take it off of your shoulders. 
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Stephen Swaffer

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Re: brain storm an optimal human safety system for back line
« Reply #518 on: June 24, 2016, 10:52:07 pm »

I wonder if any actually have a UL certified lab? I visited Milbank in Kansas City a while ago and and they did ther own UL testing.  Fairly sophisticated compared to observations from an earlier post.  Of course, they compined their testing lab with R&D- makes sense since both functions would require similar testing capabilites.
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John Roberts {JR}

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Re: brain storm an optimal human safety system for back line
« Reply #519 on: June 25, 2016, 12:40:58 am »

I wonder if any actually have a UL certified lab? I visited Milbank in Kansas City a while ago and and they did ther own UL testing.  Fairly sophisticated compared to observations from an earlier post.  Of course, they compined their testing lab with R&D- makes sense since both functions would require similar testing capabilites.
I am not sure I understand the question. At Peavey we had our own in house agency approval dept. with test equipment to test all kinds of stuff (lots of RF sniffers etc)... In fact i am still in touch with the Peavey in house engineer, in case I need that kind of advice.

It is logical for large companies to do their own testing.

I tried to get a third party test agency to quote my outlet tester and they declined.

It's just time and money....

JR
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