19 Feb
2010
19 Feb
'10
11:22 p.m.
On Friday (02/19/2010 at 08:20PM +0000), Tony Duell wrote:
Right... I think the OP said his problem occurred on a Wang or somesuch
drive. Not a Siemens. I simply offered that on the Siemans, the choke
was there to filter the supply to the motor... presumably to keep
motor hash from getting back onto the 12V rail. My thinking was that
something similar was going on in the drive that he has... without me
knowing anything about the drive that he has obviously.
Chris
--
Chris Elmquist
On the Siemens
drives also used in the H89 and H17, there is an inductor
in series with the +12 to the spindle motor. It's a hash choke that keeps
the motor noise from going back into the +12 rail. When the grease in
the spindle motor gets old and sticky, the motor draws way too much current
at startup (if it ever does start spinning) and toasts this inductor.
If this is the Siemens drive used in the Z90, I have the schematics here
(io the Z90 hardware manuals). I can't see an 'L5' at all, but the drive
I have has a separate motor control PCB with a series choke (but a 10uH
one) in the supply line. It's easily posible that later drives put
everything on one PCB (as Tandon did).