28 Apr
2011
28 Apr
'11
1:09 p.m.
-----Original Message-----
From: cctalk-bounces at classiccmp.org [mailto:cctalk-
bounces at classiccmp.org] On Behalf Of Tony Duell
Sent: 28 April 2011 20:31
To: cctalk at classiccmp.org
Subject: Re: new here
I loaded one of the +5V outputs on one of the backplane connectors and
tested every 5V output I could find on the backplane connectors, they were
all the same voltage. I used a 6V headlamp bulb on the 5W part, so drew
about 1A. I could try again to make doubly sure and perhaps load one of the
other 5V outputs. Do you know off hand which output is the one for the
memory so I can load that too. I have two 6V bulbs available to me now so I
can load logic and memory if I know which is which. Would you recommend me
using the 21W filament instead? I am not sure how much current the PSU will
supply, but guess 5A should not strain it.
I have just this minute attached a dummy load to
one of the 5V outputs
and powered it on. Using a multimeter I measured 5.4V on the 5V
outputs and
There are 2 independant 5V outputs on this supply, the logic +5V and the
memory +5V. Which one did you load, and did you check both of them?
15.8V on the
15V outputs. I ran it with just the fans running (forgot
to disconnect them) for about 5 minutes and then switched it off. Are
those
The fans are not a worry. The fans themselves are simple AC motors and
will not be damaged by (sensible) overvoltage. The fan control electroncis
might be, but that's on the PSU control board, not in the fnas themselves. it can be repaired.
no
voltages within tolerance do you think? They seem
close enough to me
to warrant putting some boards back, but I would like a second opinion
before risking the boards.
The 5V is a little high, biut no hgih enough to do any real damage. I have ideawhat load you used, it may well be that with more
load it gets closer
to
5V.
I think it;s safe to try the boards and see what happens. I would re-check
the
PSU votlages with the boards fitted, though, in case
one of the drops when
mroe heavily loadesd (this can cause some diffiuclt to trace faults, well,
dififuclt to trace if you don't check the PSU
voltages...)
strup
I am not sure what you mean by barrier strips,
you mentioned them
before but I could not see what you are referring to.
It's a type of screw terminal block .The basic construction is a plastic with little metal plates fixed to it. Each plate has 2
screws that you can
fix
wires under. There ar plastic ridges, or barries;
between the plates so
that
odd ends of wires on one matal plate can't come
into contact with an
adjacent plate, hance the name.
I think Farnell and RS sell them under that name, a look at either web
site
will give you a picture.
In that case I think I do know what you mean, it is just that there are no
red wires, just black ones.
-tony