Maintenance modems and power failures

Joseph Lapolito jml at
Fri Feb 12 06:14:25 UTC 1999

We have been using a DC powered 28.8 modem made by
a company called WTI.  

It is basically a USR modem ripped open put into a rack mount
chassis and converted to take a .25amp DC feed.

They have worked well for us so far.


At 01:54 PM 2/10/99 -0600, Sean Donelan wrote:
>Hopefully some people will find this related to the operations of their
>Ah, maintenance modems.  Why do they always seem not to work just at
>the moment you need them.
>PG&E released their report on the San Francisco power outage in December.
>Most of it was the information previously reported.  One interesting
>thing was PG&E lost access to three of their SCADA remote monitoring
>units because the modems were plugged into utility power instead of
>a UPS.
>Most network providers are aware of the secret hiding in most of our
>POPs.  Those little sporters and courier modems stuffed into a rack
>somewhere plugged into the nearest available outlet, as the only
>out-of-band access.  Has anyone come up with a solution for powering
>these forgotten pieces of equipment, which doesn't cost more than
>the modem itself?
>At first you might think it makes sense to power them off the UPS
>which is powering the rest of your equipment.  The only problem is
>if you are using the maintenance modem to monitor your UPS.  This
>is just one of those things which has bugged me for a few years, but
>I still haven't come up with a solution I really like.
>Sean Donelan, Data Research Associates, Inc, St. Louis, MO
>  Affiliation given for identification not representation
Joseph Lapolito			300 Federal Street 
Sr. Network Engineer		Andover, MA 01810
NaviNet				508-552-3379 off.
jml at			508-552-3500 fax

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