power (ups) systems

From: Fred N. van Kempen <Fred.van.Kempen_at_microwalt.nl>
Date: Sat Feb 22 21:22:00 2003

All,

While rewiring the VAX Lab here, I found something weird is going
on with the power usage on the network.

First, some stats:

UPS 1: 2400VA, mains load 220VAC (Compaq)

UPS 2: 2200VA, mains load 220VAC (APC)

All power is 220VAC, 50Hz, single phase. Regular European power,
so to speak. No weirdness there. The Compaq UPS is connected to
the Compaq servers and related (MicroWalt Corp) equipment. This
is the PROD network.

The APC (new in town) is for the VAX stuff and related equipment,
and powers all of that. For now, an 4100, a 3100 and some hub/
router/DECserver et al equipment.

Here comes the fun part. All this *used* to be on the Compaq UPS,
and it was fine, just at 96% of its load.

Now that things are split out... the compaq screams even *more* at
me, even though its reported load is ~1650VA.

My real question:

  These UPSes have 3 load segments each. On the Compaq, I currently
  use *2*. Is this the reason for its screaming? Does the total
  load come from the three segments?

Call me stupid, this I cant figure it out. I probably should not be
doing this at 4am :)

Cheers,
        Fred
Received on Sat Feb 22 2003 - 21:22:00 GMT