13 Mar
2005
13 Mar
'05
5:11 p.m.
At 07:40 PM 3/13/05 +0000, you wrote:
Ah! OK now I'm following you. Yes the 9845 PSU is a BEAST! I've worked on
a couple of them. I got lucky with my first one. The wires on the large
heavy inductor had sheared off at the PCB board so it wasn't hard to fix.
I'm still not sure how they (UPS) managed to mishandle it and cause the
wires to shear but not do any other damage.
At 03:59 AM 3/13/05 +0000, you wrote:
Sorry, I am talking about the 9845 PSU here, not the Integral (it sort of
topic-drifted). In the 9845, the LEDs are visible on top of the PSU
casing with the top cover of the machine removed.
BTW, there are 4 LEDs on the control board, visible through a slot in the
cover. These should all be on -- they're connected to the +ve and -ve PSU
control board supplies (I can't rememebr if before or after the
3-terminal regualtors) and one supply derrived from each main chopper.
That's interesting! They're not mentioned in the service manual and
they're not shown in the schematic. Are they visible without taking the IPC
apart? I should take a close lot at mine and see if they have them.
There are no LEDs on the Integral PSU. The Integral PSU is a very
conventional SMPUS, actually. The only odd feature is that triac to blow
the fuse if you connect it to 230V mains when set to 115V.
I saw that but wasn't sure what it was for. That's carrying protection
to extreme.
BTW Tony, if you don't object I'm going to save all these messages and
see about putting together a FAQ page for the IPC. I've been thinking of
putting up an IPC webpage for some time but haven't gotten around to it.
Joe
-tony