[132877] in North American Network Operators' Group
Re: Want to move to all 208V for server racks
daemon@ATHENA.MIT.EDU (Kevin Day)
Thu Dec 2 13:13:25 2010
From: Kevin Day <toasty@dragondata.com>
In-Reply-To: <alpine.LFD.2.00.1012021858270.2841@filebunker.xip.at>
Date: Thu, 2 Dec 2010 12:13:09 -0600
To: Ingo Flaschberger <if@xip.at>
Cc: NANOG list <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Dec 2, 2010, at 12:08 PM, Ingo Flaschberger wrote:
>>=20
>> For standard 110V service, you use a single-wide breaker and send one =
hot phase + neutral and you get 110V. The difference between two phases =
is 208 volts though, so you use a double wide breaker and can send to =
device without using a neutral wire. Just 2 hots and a ground. If that's =
all you're doing (you don't need legacy 110V service anywhere) you skip =
the ground wire going into the panel entirely.
>=20
> that one looks dangerous.
Err, I meant "skip the neutral wire". It's still grounded. And there are =
normally significantly more covers over the panel than this, there were =
a dozen screws I had to remove to expose all of this. :)
This is a much smaller scale panel though, not far up from a typical =
home system. The more current you start talking about, the more isolated =
everything becomes until you wouldn't even be able to see the bus bars =
like in this one.
-- Kevin
