Once upon a time, Joe Greco <jgreco@ns.sol.net> said:
> And I don't like not having anywhere to plug in my power screwdriver's
> recharger... I suppose I should see if I can find someplace that has
> a transformer of an appropriate size, or does anyone already have the
> part number for something that can provide a few hunderd milliamps of
> 120V from 208? 
Isn't 208V usually provided as a connection across two phases of a 3
phase circuit? In that case, you get 120V by going between one phase
and neutral (no transformer required).
Yes, but this doesn't imply that you have access to those other phases.
It is easy enough to be delivered 208V single phase service in a data
center environment.
... JG
Joe Greco wrote:
Once upon a time, Joe Greco <jgreco@ns.sol.net> said:
And I don't like not having anywhere to plug in my power screwdriver's
recharger... I suppose I should see if I can find someplace that has
a transformer of an appropriate size, or does anyone already have the
part number for something that can provide a few hunderd milliamps of
120V from 208?
Isn't 208V usually provided as a connection across two phases of a 3
phase circuit? In that case, you get 120V by going between one phase
and neutral (no transformer required).
Yes, but this doesn't imply that you have access to those other phases.
It is easy enough to be delivered 208V single phase service in a data
center environment.
... JG
Correct. I have a Smart-UPS RT connected across two legs of 3 phase for
208. The unit does not have a neutral, only ground, so it's 3 wires in
and 3 out. The output is only 208 L-L with odd voltages on L-G. Since
there's no neutral, it can only be used to drive 208 loads or a
transformer for 120.
~Seth
Uh. 208v single phase is functionally the same as 240v single phase. You grab 1 hot, neutral off the ground, and you have a common 110v circuit. Even if you're 3 phase to your PDU, it's still single phase to the servers. (specialty gear excluded, but those generally plug direct to the circuit, not to a PDU).
This makes it very very easy to solve this problem, and I keep a few of these floating around at all of my datacenters, with big labels saying who they belong too. (ignoring the fact that for drill charging at least there's usually house power available, but crash carts need these...)
C14 (M) to 5-15 (F) adaptor cable:
http://www.cdw.com/shop/products/default.aspx?edc=1036852
I also use them to run wall warts, etc, as needed.