nanog mailing list archives

RE: 80 AMP power controllers?


From: Shawn Solomon <ssolomon () ind net>
Date: Tue, 5 Mar 2002 20:58:45 -0500 (EST)



Chris,

Steve has a few good points that you should really consider before
furthering your quest.

Determining your REAL load is a first..  I'm not saying you will find some
"headroom" here, but its a good place to look.

Determine if you can cut the power in smaller quantities, or if you really
must be able to remotely kill 80amps at once.

If you really must toggle the full 80amps, i'm going to think you should
investigate getting some "virtual hands" contracts for your locations.  On
site work force in COs can be very helpful.  Also, considering your
situation, they may be more than willing to be participating in your
events.

80 or 160 amps of power can be quite alot to some smaller plants, and
definitely enough to really aggravate the equipment which monitors the
smaller plants.  Switching that much load attached to a small plant could
really cause you and your CO some problems...   But, if you are attached
to a much larger plant, it may not be such an issue.

In either case, I'm sure the CO would be happy to assist..  And with the
right "messaging" of your local sales drone, it could be a very cost
effective solution.


On Tue, 5 Mar 2002, Steve Naslund wrote:



Are you absolutely sure about the 80 Amps requirement ?  That is absolutely
huge for DC powered equipment.
You might want to check out the following manufacturers :  APC, Lorain, and
Reltec.  All of these companies
have DC power divisions.  Lorain is probably the biggest and is used by most
ILEC central offices.  I have not
ever heard of a dial up power controller that works at this current level
but you could probably get an electrician
to rig something up so that a lower powered relay could trip the higher
powered feed for you.  This will not work
if you are going into a facility that must be NEBS compliant (i.e. a central
office) because such a setup will almost
certainly not meet the standards since it must be tested as a unit.

I would also beat up the manufacturer to add a remote management capability
to the box.  For example, you might be able to get a modem that will allow
you console access to the device.  We have looked into this and found that
a) there are very few if any NEBS compliant remote switchers and b) there is
often no need to power cycle a box as long as you have remote console
access.  I think this would be better because most DC breakers at 80 amps
should not be used as a power switch.  We have looked into this and found
that a) there are very few if any NEBS compliant remote switchers and b)
there is often no need to power cycle a box as long as you have remote
console access.

You also might want to get an ammeter and see what the equipment is actually
drawing because I doubt it is near 80 amps.  Often these figures are very
worst case.  They are usually with a fully loaded chassis running on a
single power supply.  There is no danger if you use a lower rated breaker
other than the equipment tripping it during full load.  Lastly, be sure all
of your cabling is sized right and that your connectors are absolutely
perfect.  At this current level you can really get a good fire going or
light yourself up.

P.S.  I just realized that I used NEBS without explaining it.  NEBS is a
standard adhered to by most telcos.  It stands for Network Equipment
Building Standards.  It is a process of testing and engineering (kind of
like the UL testing on consumer products) that rates the equipment for
safety, fire prevention, and reliability.  You cannot put a device in the
central office without this rating.  I would also use this rating on any DC
equipment I bought whether or not it is required just as a sign of proper
engineering and testing.

Steven Naslund
Network Engineer
Allegiance Telecom

-----Original Message-----
From: owner-nanog () merit edu [mailto:owner-nanog () merit edu]On Behalf Of
Chris J. Robb
Sent: Tuesday, March 05, 2002 11:24 AM
To: nanog () merit edu
Subject: 80 AMP power controllers?



Greetings. I may have the need to drive a piece of networking equipment
with a DC input requirement of 80 AMPS, possibly 90. For remote
management, we need the capability to power cycle the box remotely through
dial-up. There will be redundant power, so two 80 AMP feeds will be
required.  Sentry has a box that can split two 100 AMP feeds into two 70
AMP feeds toward our equipment. That's about as high as I can find. What
do the larger carriers use? (Or to they just use remote hands at the POPs
when necessary.

Thanks!

-Chris

--
Chris Robb
Indiana University





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