Why choose 120 volts?

david raistrick drais at icantclick.org
Wed May 27 17:30:20 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.

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?  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)

I also won't argue using ground for neutral, that's like arguing bonded vs 
unbonded panels.



---
david raistrick        http://www.netmeister.org/news/learn2quote.html
drais at icantclick.org             http://www.expita.com/nomime.html





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