I suspect that service manuals for this type of industrial equipment may
only be available to authorized service centers.

It's possible that any used VFD may have had a fault before it was subjected
to mechanical shock, so the fault may now be a combination of faults.

Milti-layer boards such as computer motherboards are more difficult to find
cracks on, but double-sided single layer boards are fairly easily inspected
with a bright light source behind the board.. a high brightness LED may work
well, but a high powered LED (not just numerous HB types) will definitely
work.

General close inspection procedures follow, and a good magnifier lamp is
very helpful. A quality handheld magnifier may be sufficient with
exceptionally good lighting (not just glare into your eyes).

The heavier objects in the unit are most susceptable to mechanical shock
damage. Production soldering techniques may be fairly good in industrial
equipment, but minor defects may still get passed over in testing/burn-in
phases.

Typical procedures generally involve disassembly and reseating of all
internal connectors, and checking for loose hardware.

Paper and notes can be critical to proper re-assembly. Some folks use
digital cameras to record details.

If trouble spots aren't found with the previous steps, circuit
troubleshooting often involves checking various circuit paths in the unit
without power applied, typically making schematic drawings and educated
guesses along the way.

Much of the electronic equipment manufactured in recent years fails without
any obvious signs to be spotted on a casual visual inspection.. many of the
"smart machines" designed recently just fail to operate when component
faults arise.

--
WB
..........


"Dave H." wrote in message
...
In case no-one noticed my attempt to hijack the 10EE motor thread, does
anyone have or know where I can get a service / repair manual or schematic
for the ABB ACS-301-4P9-3 VFD? I have it up and working (spins the drive,
speed control and fwd/rev work) but DHL managed to drop it (from quite a
height) in transit and there's no DC to the control/programming panel so I
can't get in and set the various motor and braking parameters... The
control board (not the programming panel, the top board in the main unit)
is all surface-mount and multi-layer, and is going to be a sod to trace,
although no so hard to add a few repair jumper-wires if I can find what's
broken and where.

I've tried ABB's UK distributors, their answer was "we don't keep
spares/manuals/schematics for anything that old so buy a new one"!

I'd rather not, as it's oldish and so has been easily hacked to fool it
into thinking it has 415V in and thus it can run the Difficult Motor in my
Holbrook (England's Monarch?) C13 - 415v only, 3-phase, 3 sets of windings
for the 3 speeds - and, of course, I'm cheap and broke

Thanks all,
Dave H.
--
(The engineer formerly known as Homeless)

"Rules are for the obedience of fools, and the guidance of wise men" -
Douglas Bader