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Portable UPS on isolated ground circuits #215212 03/23/15 04:48 PM
Joined: Jul 2007
Posts: 1,335
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sparkyinak Offline OP
Member
Hi,

Maybe one of you can save me some homework. Any reason not to plug a portable UPS is isolated ground circuits?


"Live Awesome!" - Kevin Carosa
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Re: Portable UPS on isolated ground circuits [Re: sparkyinak] #215213 03/23/15 06:11 PM
Joined: Jul 2004
Posts: 9,392
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gfretwell Offline
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I can't think of anything.
I do think IG is largely snake oil tho.
IBM stopped recommending them about 40 years ago. There was no demonstrated benefit.


Greg Fretwell
Re: Portable UPS on isolated ground circuits [Re: gfretwell] #215214 03/23/15 08:47 PM
Joined: Mar 2004
Posts: 947
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twh Offline
Member
Originally Posted by gfretwell
I can't think of anything.
I do think IG is largely snake oil tho.
IBM stopped recommending them about 40 years ago. There was no demonstrated benefit.
I don't know about that. I did quite well off them.

Re: Portable UPS on isolated ground circuits [Re: sparkyinak] #215215 03/23/15 10:37 PM
Joined: Jun 2004
Posts: 1,273
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Tesla Offline
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IG came to be quite the 'cause' when computers entered filthly electrical systems.

To go down the list:

Crossed over polarities -- far, far, more common than they should be -- so many out there tying their best to give us more repair work...

Over loaded circuits -- until digital logic came along sagging voltages passed largely without remark...

&&&&&

I've never encountered an IG installation in commercial service that was not companion to an isolated power system: an SDS. ( Secondarily Derived Service )

They went together like bread and butter.

It was a LOT cheaper to just drop these in rather than re-work and correct a fundamentally screwed up building -- some of which were bona-fide antiques.

Now that decades have gone by -- and ABOVE ALL -- with the rise of laptops in general office use (which have intrinsic isolated power and secondarily derived services -- every last one) the passion for IG and isolated power has evaporated.

It won't be coming back any time soon.



Tesla
Re: Portable UPS on isolated ground circuits [Re: sparkyinak] #215216 03/24/15 03:56 AM
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gfretwell Offline
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The dirty little secret was IBM figured out they had found the enemy and it was us.
Virtually all of the noise in office electrical systems was coming from the switcher power supplies in our equipment.
When we put in the line filters we should have been using from the git go, it stopped being an issue.


Greg Fretwell
Re: Portable UPS on isolated ground circuits [Re: sparkyinak] #215219 03/24/15 02:24 PM
Joined: Apr 2002
Posts: 7,111
HotLine1 Offline
Member
IG circuits, panels, and receptacles generated a lot of $$$ back in the day.

The search for 'clean power' for the electronics gurus went to motor/generator sets, and active UPS units. That was not your 'standard' offices, but research & prototype EEs in the 'chip making' fields.



John
Re: Portable UPS on isolated ground circuits [Re: sparkyinak] #215220 03/25/15 12:54 AM
Joined: Jul 2007
Posts: 1,335
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sparkyinak Offline OP
Member
My neck of the woods is largely behind the times electrically. I have offices wired in Romex of a marginal utility not connect to a grid, no IG, No surge protection, ground rod and connection to water pipe ground, frequent brown, blackouts, spikes from eagles flying into the lines, diesel generator back up and no problem with electronics. The more protected systems, like IG, ground rings, system wide surge protection, overrides neutrals, and the like seem have more problems. Lol!


"Live Awesome!" - Kevin Carosa

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