[Emc-developers] phony vfd's

[Gene Heskett]

Greetings all;

As most might remember, I have one of those phony vfd's with only about
32 adjustable parameters. 1.5 hp rated, its driving a 1 hp Century 3
phase motor that normally expects 230 volt 3 phase power.

I have one admittedly small problem in my current lashup to drive this
lathe.

If I get a trip-off, from say a following error, my present setup which
uses the machine enable signal to switch on the power for the vfd and
stepper drivers is turned off by the fault.

I either have to restore that quickly, before the vfd's capacitors fall
to the undervoltage error trip, or wait for it to time out completely,
killing its panel display. Thats an annoying pause of at least 20
seconds.

This vfd has no rs-422/485 interface, not even a spot for it on the
pcb's, so I am running it with a Mesa Spinx1. And other than this, its
happy as a clam.

If power to it is restored after its panel reports the UV condition, I
either have to hit the f2 to shut it off again, and wait for the final
timeout, something in the 20-25 second range, or pull up a small step
stool so I can reach its red reset button. Its on the top of the motor
driver box, and the garage door just clears it as it moves.

Does anyone know of a cheat method to exert a reset to such a dumb
device?

Cheers, Gene Heskett

[andy pugh]

Post by Gene Heskett
Does anyone know of a cheat method to exert a reset to such a dumb
device?

To reset the main (ground fault) breakers on my aged mother's fuse box I
rigged up a string and pulley system to somewhere that did not involve her
finding a step-stool and standing on the kitchen counter.

(It is debatable whether a fuse box is even allowed to be in the same room
as the kitchen under current regulations, but it would be a lot of trouble
to move it)

[Gene Heskett]

Post by andy pugh

Post by Gene Heskett
Does anyone know of a cheat method to exert a reset to such a dumb
device?

To reset the main (ground fault) breakers on my aged mother's fuse box
I rigged up a string and pulley system to somewhere that did not
involve her finding a step-stool and standing on the kitchen counter.
(It is debatable whether a fuse box is even allowed to be in the same
room as the kitchen under current regulations, but it would be a lot
of trouble to move it)

Yeah, our N.E.C. grandfathers a lot of that, but you're nailed to the
cross if you have to open it to replace a duplex socket or any other
sort of rework. Then you have to bring the whole branch fed by that
breaker up to code. Theoretically... For obvious reasons its rarely
done. The duplex is 89 cents, the rework might need a thousand due to
the time involved, drywall rework yadda yadda. Its been working for 40
years, what would you do? Don't answer, it could be costly. :(

That mechanical method had not crossed my aged wet ram, but could be
rigged I guess. I also had visions of finding the xy of that button on
the ribbon socket and banging it with a reed relay. With a rubber
grommet on the button pusher to prevent damaging the membrane covering I
can see it working in my mind. But these buttons do take a "sturdy"
push, 50x the force the average membrane keyboard takes. I'll see what
I can rig that still allows me access to the panel to program it.

Thanks Andy.

Cheers, Gene Heskett

[Gene Heskett]

Post by Gene Heskett

Post by andy pugh

Post by Gene Heskett
Does anyone know of a cheat method to exert a reset to such a dumb
device?

To reset the main (ground fault) breakers on my aged mother's fuse
box I rigged up a string and pulley system to somewhere that did not
involve her finding a step-stool and standing on the kitchen
counter.
(It is debatable whether a fuse box is even allowed to be in the
same room as the kitchen under current regulations, but it would be
a lot of trouble to move it)

Yeah, our N.E.C. grandfathers a lot of that, but you're nailed to the
cross if you have to open it to replace a duplex socket or any other
sort of rework. Then you have to bring the whole branch fed by that
breaker up to code. Theoretically... For obvious reasons its rarely
done. The duplex is 89 cents, the rework might need a thousand due to
the time involved, drywall rework yadda yadda. Its been working for
40 years, what would you do? Don't answer, it could be costly. :(
That mechanical method had not crossed my aged wet ram, but could be
rigged I guess. I also had visions of finding the xy of that button
on the ribbon socket and banging it with a reed relay. With a rubber
grommet on the button pusher to prevent damaging the membrane covering
I can see it working in my mind. But these buttons do take a "sturdy"
push, 50x the force the average membrane keyboard takes. I'll see
what I can rig that still allows me access to the panel to program it.
Thanks Andy.
Cheers, Gene Heskett

An attack of dumbass on my part, one really ought to re-read that little
pamphlet that came with it, turns out that it does have a separate reset
input, pull input terminal 10 to ground, presumably for a few
milliseconds. The Spinx1 doesn't have an isolator output for that, but
since its a 12 volt circuit, and I do have a 4 channel opto that can
handle that with one channel. So that problem is solved & all I need to
do is get off my duff, mount that board and wire it up, and plug another
1 shot into the hal file to tickle it for 50 milliseconds.

I found some Chinese AXA tool holders on ebay, for $11.50/copy and some
of them were making my mailbox sag a bit this evening, 7 of the first 2
styles (101-102) in the drawer now, and some 1/4" square tool steel. I
bought the 1/4" for the boring bar that came with the lathe, but I had
to drive the 1st piece in with a hammer, so obviously that 3/4" x 1/4"
bar has been abused. Looks like I'll have to chuck the bar up and reduce
the end diameters about 3 thou before I can actually remove the bar from
the bar holder as both ends are fat enough that the bar cannot be
removed from the bar holder.

Such stuff keeps me out of the bars. But you knew that. :-)

I do hope that those of you with children close enough to visit do get a
visit this weekend since its Fathers Day on Sunday on this side of the
pond. I may get a phone call or 4, but since three of my remaining 4
are "West of the big muddy", nearly 2k miles away, a visit would indeed
be a pleasant surprise.

Cheers, Gene Heskett