NOOOOOOOOOOOOOOOOOOOOOOOOOOOO!!!!! Stupidity Strikes Again!

From: Tony Duell <ard_at_odin.phy.bris.ac.uk>
Date: Wed Nov 5 04:25:12 1997

On Tue, 4 Nov 1997, Daniel A. Seagraves wrote:

> While moving the 11/34 to a more lighted area, I broke the power switch
> off the back. Now it doesn't power on. I need a WHOLE NEW POWER SUPPLY!

Prepare to be roasted :-)

YOU DO NOT NEED A NEW PSU. You never need a new PSU - repair the old one.
It's not that hard (at least not for this fault), and it's a lot easier.

OK. Now for some advice. It's not a power switch, it's a circuit breaker.
It does the job of the fuse as well. The 2 parts are interlocked so that
if either of them trips they both turn off. You may be able to frob the
remains of the handles to the 'on' postion, but only if you get them both
there together.

Breaking the handles off the breaker is just about the most common thing
to happen to the BA11-K (11/34, etc) box. I've even seen people bolt a
little metal shield over the breaker (using 2 of the mounting screws) to
protect it.

OK, the worst part is getting the old breaker out. Unplug the power cable
(the breaker is in the mains wiring, of course), remove the top of the
CPU, remove the lower 4 screws that hold the PSU to the rest of the
machine and loosen the upper 2 (do not remove them). Now tip the machine
onto one side (if it's not in a rack) or turn it on the slide brackets (if
it's in a rack). Pivot the PSU away from the CPU (using the top 2 scres as
pivots).

Now you'll see a little chassis in the middle of the PSU at the bottom.
The breaker is part of that. Unplug the cables from the front (4 pin to
the transformer primary, 3 pin to the power switch on the panel, edge
connector to the control board). There may be an earth wire as well. Now
undo the 3 countersunk screws on the bottom of the chassis and slide it
out towards the rear of the machine.

It's now trivial to replace the breaker (4 screws and 4 wires with push-on
tags). I'd send you a spare if I had any, but I only have the
lower-current ones for 220V machines. But it's a standard part and you
should be able to find one in the catalogues over there.

Don't try to mend the old one. It won't hold and you'll just be wasting
your time.

> Damn! I hate myself sometimes!

> That was a Stupid, Stupid, Stupid Mistake!

We've all done similar things...

>
>
>

-tony
Received on Wed Nov 05 1997 - 04:25:12 GMT