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Topaz placement event sequence question (long, rambling)

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#51773

Topaz placement event sequence question (long, rambling) | 13 September, 2007

If someone knows specifically what the sequence of events is in a Topaz placement step I'd appreciate it if you could share that with me. We've developed an intermittent problem with ours where it places the part and immediately stops with E0873.

The possible causes are many according to the error description on screen, but it seems most likely to be a function of placement vacuum. In this case the vacuum remains on (both physically at the nozzle and in the I/O) after the part is placed. Resetting the machine results in the nozzle tapping the part down into the paste and erroring out again so it's still trying to place the part.

It seems like it doesn't recognize that it's dropped the part, so is my vacuum level too high after placement? Not sure what it should be with an open #31 nozzle on there but the vacuum sensor levels show 91 w/o a nozzle, and 222 plugged.

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#51778

Topaz placement event sequence question (long, rambling) | 13 September, 2007

Just a little status update.

When it's running and I monitor the I/O, the mount vacuum bit never turns over to 0. It may be turning over enough to run, but not long enough to see on screen. It stays at 1. When it errors, I can trip it by putting my finger over the vacuum port for that solenoid valve. Once it's turned, it'll run until the next occurrence.

Question is, what do I change to resolve the issue?

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#51785

Topaz placement event sequence question (long, rambling) | 14 September, 2007

Good morning,

Those random stops are typically related to wrong vacuum limits calibration. Have you calibrated vacuum limits for each nozzle?

BR, Pavel

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HAR

#51788

Topaz placement event sequence question (long, rambling) | 14 September, 2007

Out of curiosity, I measured the vacuum levels on our Topaz. With a #31 nozzle the values read somewhere between 130 and 150 when open and about 200 when blocked. The component pickup works fine with no errors with these values

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#51792

Topaz placement event sequence question (long, rambling) | 14 September, 2007

After considerable head scratching yesterday afternoon I've determined that this is a symptom of flaky wiring, a loose connector, etc.. The head 1 mount vacuum bit isn't changing all the time on the blow off, and it errors out at that point. When I reseated all the available connectors in that circuit it ran fine, although I did see that bit flicker on occasion. I need to keep an eye on it and see if it continues to be a headache or if this resolved it "permanently". Thanks for all of your comments.

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#51794

Topaz placement event sequence question (long, rambling) | 14 September, 2007

Are you sure there wasn't solder stuck up the nozzle. Which would make for a doggy pressure indication?

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#51795

Topaz placement event sequence question (long, rambling) | 14 September, 2007

100% positive. First thing I did was check the nozzle, plus it was happening with all nozzles on head 1.

It's definitely in the circuit somewhere.

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#51812

Topaz placement event sequence question (long, rambling) | 17 September, 2007

Then look for a disconnected supply or earth to the head. A dodgy cap (high ESR) on the supply of the board. Put a CRO on the supply and check it's supply and earth to chassis and to each other and then compare the level to other boards in the machine.

regards Andrew

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