PRTAlpha Z-Zero Plate Stopped Operating

[mike]

Hit reset...narrow yellow line remains in #3 input. Just noticed that I have always had the red wire from the Z-zero plate cable connected to the +5 input on the far right terminal. On the left near the E-stop is the +5V stud. There is not terminal block with screws, so I have never connected anything to that post. Because the Z-zero plate and clip only involves the black and green, plus the plate has worked properly for years, I don't think the red wire is involved...Right? I looked in my literature and didn't find any explanation about the #3 input light. Can anyone tell me about it? I sincerely appreciate all your input.

[garyc]

Mike...
Yellow Line in a green circle is normal position for a normally open limit as in the PRT. This would not be correct for a PRS machine.

The red +5v wire that goes to the ZZero plate or connector is to power the probe. It is not needed for normal operation of the ZZero plate

[gene]

I think he has a PRT Alpha and not a PRS

[mike]

Moved ground...no light in #1 input. Has anyone ever detected the narrow yellow line in #3 input light? I have really messed up things. Machine has lost positions. X and Y moving 50% of specified move directions. When I mess up I do a good job. Of course, this occurs just as I'm scheduled to mill MDF doors for a local cabinet shop. I'm digging out the Shopbot Setup instructions...haven't looked at that in years.

[Brady Watson]

Don't panic.

Ignore the Input 2 & 3 lights.

Get into SB3 and run the UR command. Hit Enter 3 times. Under 'Older ShopBots', select PRTAlpha (if you have AS98AA-T7.2 motors, choose the one that has 7.2 after the name). This should fix your movement distance.

If output 4 flashes, use the VN command to change "Switch#4 STOP Type" from normally closed to normally open.

Then do the following:

Pull out the Zzero plate wires from the blue screw terminals. Move the ground wire to it's own discrete ground terminal somewhere down the line on the blue terminals (don't be afraid to strip insulation back to make wires a little longer) - then make sure ground wire and black input #1 wire are fully seated in the blue terminal strip AND if you removed the blue terminal blocks from the board that they are not off a pin...make sure they are where they are supposed to be on the board.

Want to get the Zzero working for SURE? Run a ground wire from the chassis of the machine (anywhere...make sure you have a good connection) back to the control box. Secure it on any open ground terminal on the blue screw terminal strip. If it STILL doesn't work, you've got a broken wire somewhere...and a very rare possibility that your control card is flaking out. It's a pretty simple circuit.

You can test to see if the card is flaky by putting a wire in Input 1 and short it out to gnd for a moment while looking at the input 1 light in SB3. If it works, then your issue is from the control box out to the plate.

-B

[mike]

Guys...thanks so much for the input. After I complete staining this chest, I'm going back to my bot and implement these suggestions.

[jerry_stanek]

Guys...thanks so much for the input. After I complete staining this chest, I'm going back to my bot and implement these suggestions.

If you lie out in the sun your chest will tan real nice just be careful so yo don't burn.

[mike]

Left myself open for that one...Jerry quickly jumped in and took his shot. I guess I need to be a little more specific..."blanket" chest. Jerry, thanks for keeping me on my toes. Now back to the bot... Z-zero is still inoperative. Got the correct movements for a short time. Now when I power up the control panel and press "reset" nothing happens. I think those birds that built their nest in the back of my shop have moved into my control panel. This "reset" issue occurred a few years back. I can't remember how we corrected it, so I'm going to dig into my old notes.

[Brady Watson]

Push the magnetic contactors in while pressing reset button - after you have determined that the box is getting power.

Why is the Zzero plate still not working? Did you make a jumper wire to go from input 1 to ground yet? Did input 1 light up?

-B

[mike]

Verified control box is getting power. Pressed magnetic contactors while depressing reset button...nothing. After turning on/off switch to on, then depressing reset button, you can here a slight click, but nothing. No click after depressing reset button again. i haven't located my notes from first time this occurred a fews back, so I'm starting from zero. I'll check the history on the forum...maybe someone has experienced the same issue.

Regarding Z-zero plate light...disconnected green and black wires from terminal. Connected jumper directly between #1 and GND...no light. Connected jumper from #1 to another ground in cabinet...no light. With green and black wires disconnected from terminal block, I attached clip to plate. Checked continuity at ends of green and black...good. This test isolated wires, so the wires from clip and plate are good...right? Appears we have an open circuit from the terminal block to the light...right?