On Wed, 29 Jun 2016 06:27:09 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Gunner Asch fired this volley in
:


Of all the vfds I've replaced...only one could be found that was
caused by a shorted motor. Most VFDs (NOT ALL) have internal
protections that shut the VFD down if the motor fails.


Besides... no body reads details... they just see "blown up" and presume
their own conditions.

1) the spindle ran fine on the last job, and was stopped properly before
turning off the machine.
2) on the FIRST power-up of the VFD - BEFORE ATTEMPTING TO START THE
SPINDLE - the VFD threw the fault indicated earlier. No amount of
resetting, either by keypad or application/removal of power will clear
the fault.

I was down at my buddy Glenn's yesterday and he had recently had to
replace his VFD on his drill, a large, geared VSR he uses for drilling
and tapping directly.

The 1989 Hitachi VFD was working fine one day and released lots of
magic smoke and fire the next, vaporizing several traces on the
circuit board as it went. It also blew the labels and plastic bits off
the power transistors.


Oh... and Gunner...
3) ShopSabre says they'll be switching over to Mitsubishi VFDs on all new
machines. If you need a new VFD, you can purchase an entire controller
upgrade, and they'll sell you a Mits to go along with it.

For me that means FOR SURE that I'm ripping the guts out of this toy and
putting in a decent control (and servos, I think).

There are lots of other things to do to it, also... like screw covers (of
which it has NONE). Like providing more hold-down inlets under the table
(only 4 in a 5x10 deck). Like making the hold-down grid board user-
replaceable. (It doesn't even come with a routing file to cut a new one,
and they sealed over all the screw pockets, so it requires destroying the
old sheet to get it off!)

Don't you love mfgrs who do things like that?


It does have a nice, rigid table structure, though! G (The gantry, not
so much!)

Oh, well, I wanted to add a 5th axis to this thing, anyway.

g

--
Fear not those who argue but those who dodge.
-- Marie Ebner von Eschenbach