Re: New Owner Mint3.28 hang up

You man those little surface mount caps? I have no SMT tooling to pull them
Wed 18 Dec , 2013 19:37 pm
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Re: Denstep - Baldor NO +12V -12V +5V HELP

What voltages does U16 (the L4960) supply?

Is the +5 taken from the +12?
Mon 07 Oct , 2013 19:08 pm
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Re: Denstep - Baldor NO +12V -12V +5V HELP

There's a controller card on eBay for $500,, but I have no dongle, am I wasting my time?
Mon 07 Oct , 2013 13:36 pm
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Re: Denstep - Baldor NO +12V -12V +5V HELP

Is there any history of this type problem? When I worked as a repair tech in a mfr environment, I found a mfr problem where the silkscreen lifted up a little when the PC board was exposed to light. This created a short on the top layer of a multi layer PCB. I think they were 30 meg boards, double ...
Thu 03 Oct , 2013 21:26 pm
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Re: Denstep - Baldor NO +12V -12V +5V HELP

As a side note looks like U16, the L4960 has been replaced at some point.
So that IC is suspect, but if it was replaced, then something else might be a cause,,,
Thu 03 Oct , 2013 19:46 pm
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Re: Denstep - Baldor NO +12V -12V +5V HELP

Already pulled the two KBU8D's and they test fine with my DMM. I have two replacements and just to verify, I just now compared the old with the new.

I checked the tracks from the edge connector to the rectifiers, but not sure where the other sides go.
Wed 02 Oct , 2013 22:54 pm
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Denstep - Baldor NO +12V -12V +5V HELP

Denstep Controller with a Baldor Optmized controller board F391 Issue 2
We have 24 VAC going into the board and fuse F1 is good., but no +12 -12 +5 volts.
I have no schematic drawing and the link here to st.com doesn't work

Since all voltages are gone, I would suspect a component that uses all ...
Mon 30 Sep , 2013 14:27 pm
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Re: Blown Drive Chip on Baldor board

Steve wrote:
See the attached link for information on the circuit.


https://www.st.com/stonline/books/pdf/docs/1734.pdf
Bad Link any hope in finding a good one?
Mon 30 Sep , 2013 14:02 pm
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Re: New Owner Mint3.28 hang up

Removed the bridge rectifiers, but they test good,,,

What's the most likely issue pulling the +12 and +5 volts down?

What could pull both voltages down?

Any possibility of getting a schematic for the Baldor Optimized Control F391 issue 2 PC Board?
Sat 28 Sep , 2013 22:26 pm
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Re: New Owner Mint3.28 hang up

Removed all connectors but the 24VAC in to the Baldor board.
No LED light.
I then removed the piggyback board (with the LED) and still no volts,,, suspecting the diodes again.

On a side not, it's 28 VAC RMS according to my meter, but that's probably cause it's unloaded.
Thu 19 Sep , 2013 15:01 pm
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Re: New Owner Mint3.28 hang up

After some serious investigating (and reading the user's manual) I've determined that the key switch is a momentary switch.

So I'm thinking, maybe, cross my fingers, maybe, tying the two orange key switch wires together, might have preveneted Voltages.

I put the entire thing back together (had ...
Wed 18 Sep , 2013 18:31 pm
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Re: New Owner Mint3.28 hang up

Back with another stupid question,,, the keyswitch, is it momentary, or On/Off?
I don't have a key and hard wired the two orange wires together.
Tue 17 Sep , 2013 15:59 pm
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Re: New Owner Mint3.28 hang up

Looks more like a Denstep, with 24VAC supplied for both drives and logic.
And from looking at the Denstep schematic, looks like the E stop cuts power to the Xformer
I have 24VAC, so it's not a bad E stop button.

Since the logic doesn't like 24VAC, (as per an earlier post) is there a "fix" I can do ...
Tue 17 Sep , 2013 15:45 pm
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Re: New Owner Mint3.28 hang up

Got the Baldor board out, easier than I thought
From what I'm piecing together, the Spindle drive is a small pc board that sits above the transformer.
Looks like there is a jumper (blue wire) between TB1-6 and TB1-2 (Stop and Grnd)
Looks like I have some type of mutation between smartstep and next ...
Tue 17 Sep , 2013 15:34 pm
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Re: New Owner Mint3.28 hang up

TY, I couldn't tell by just looking at them, and didn't want to go Yanking on a UK board. (Pun intended)
Tue 17 Sep , 2013 14:36 pm
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Re: New Owner Mint3.28 hang up

I am SMT solder certified by Data General,,, used to work on 4 meg double sided SMT PCBs,,, about 18"x6" in size

I would very much like to get this machine up and running, but buying a new Board is out of the question, as is being able to afford a tech to fix it.

Do the Orange connectors remove ...
Tue 17 Sep , 2013 0:09 am
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Re: New Owner Mint3.28 hang up

Would like to verify, but I think the KBU8D rectifiers are pretty much toasted, as I dont have +5 +12 -12 volts.
So what kind of challenge is it to replace the rectifiers?
How do the Orange conenctors come off the board?
Do I need to do anything with the drive transistors on the big heatsink? Or ...
Sun 15 Sep , 2013 18:01 pm
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Re: New Owner Mint3.28 hang up

From what I've seen, it's looking like the two big rectifiers on the Baldor board are fried.
IMG_6387a.jpg
IMG_6387a.jpg (196.09 KiB) Viewed 21135 times
Sun 15 Sep , 2013 17:54 pm
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Re: New Owner Mint3.28 hang up

I measure 28VAC on the power in connector both between pins 1 & 2 and between pins 4 & 5. (The link showed that 4 & 5 should be DC voltage, I hvae 0 volts DC between 4 & 5. ????

Which, if I would have taken off the cable trough cover, I would have seen that pins 1 and 2 are jumpered to pins 4 and 5 ...
Sun 15 Sep , 2013 17:43 pm
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Re: New Owner Mint3.28 hang up

Not sure what I have is called, but here's a picture.
Did not get any flicker at all from the 7 segment LED when powering up or powering down.
Sat 14 Sep , 2013 16:51 pm
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