2 Jul
2013
2 Jul
'13
3:18 p.m.
On Jul 1, 2013, at 11:06 AM, Mark Tapley wrote:
This was a fiddly process, involving de-mating
connectors, switching back and forth between top and bottom of the drive, and figuring out
how to prop the drive up with some parts hinged open. However I would not call it
"perfectly impossible"
I should have been more clear that what is almost perfectly impossible is not to
disassemble and reassemble it... this sucks but can be done. What is almost perfectly
impossible is to run it in a partly disassembled state on a bench, so that observations
can be made regarding the specific failure modes.
At 18:23 -0500 6/30/13, <Dave R.> wrote:
One of mine failed this way. It's pretty obvious where the smoke came from, and
it's just another electrolytic cap.
I recapped the motor control board on one drive last night, to see how far it might take
things. The answer - not far. More effort required. I tested out one of the caps I pulled;
of its rated 10uF, only 0.04uF were left in it. So this is certainly a problem that needs
correcting, and it seems likely that the other similar caps elsewhere in the drive want
replacing as well.
There is also the issue that the electrolyte that leaked onto the motor control board has
reacted chemically with some of the solder joints so that they are mechanically unsound.
The worst two just flaked away with a fingernail. Not good.
ok
bear.
--
until further notice
I believe there are issues with dead electrolytic
capacitors among
other things. I suggest not powering on a drive without disassembling
and checking it first, though; I've heard of many cases where smoke
comes out of the drive when powered on.
Checking/replacing all the caps would take a while. The drives have a lot of parts.
However this is as good an explanation as any I've heard. FWIW, there was no smoke
from mine, then or yet (it's still powered, in my cube).