Why choose 120 volts?
jgreco at ns.sol.net
Wed May 27 18:40:39 CDT 2009
> On Wed, 27 May 2009, Seth Mattinen wrote:
> > Here's the L-G voltage off the 208v taps from an isolation transformer in a
> > system with no neutral: http://ninjamonkey.us/not_120_volts.jpg
> Not 120, but 90 give or take. 90 is at the low end of the acceptable
> range for common household 110/120v service.
Yeah, but that's L-G voltage (geez, did you even look at the picture?)
And Seth just finished telling us that it was 211 L-L:
Seth > "The L-L voltage on that same PDU is 211."
What's going to be presented at the neutral and hot of the 5-15R of the
monitor power adapter are the L and L. Think about it. Or get out a
meter and test.
> Depending on how the phases are balanced in your facility, you may see
> that fluctuate up or down, of course. If you measure hot to hot on the
> same PDU, do you get anywhere close to 208?
Yes, Seth just finished telling us that in the portion of his message you
> I'm going to suspect either
> your fairly out of balance, or you've got a good bit of voltage drop by
> the time it arrives....
> But since the concensus from those who haven't used this is that the
> device will present 208/240 at the 5-15 plug, I withdraw my suggestion and
> leave you to your own methods. (for the rest, test it yourself)
For those of us who *have* used this, we're telling you that it'll present
208/240 at the 5-15R.
> I also won't argue using ground for neutral, that's like arguing bonded vs
> unbonded panels.
No it's not. Only idiots argue for using ground for neutral. In doubt?
Ask your electrical inspector.
Joe Greco - sol.net Network Services - Milwaukee, WI - http://www.sol.net
"We call it the 'one bite at the apple' rule. Give me one chance [and] then I
won't contact you again." - Direct Marketing Ass'n position on e-mail spam(CNN)
With 24 million small businesses in the US alone, that's way too many apples.
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