Name That Problem: Z-Plate

[Educator]

First off, my name is Andy, I am a high school educator in Idaho. This is my first year teaching and I have inherited a Shopbot from an old educator. I have a strange issue that I need help with.

My Z-Zero wiring is currently not setup correctly. It is my opinion that the teacher that originally setup this machine did so incorrectly. Normally I would list the specifics of what Shopbot I have, but honestly I do not know what it is. Below are pictures of the machine.

https://lh5.googleusercontent.com/-22huVszM-8g/UKL8MyLb3qI/AAAAAAAAKyo/T2jcw0t0c50/s640/IMG_0053.jpg

https://lh6.googleusercontent.com/-FjKAbp38C3E/UKL8FD3_OCI/AAAAAAAAKyM/UtxlVzmmtWU/s640/IMG_0050.jpg

https://lh6.googleusercontent.com/-RT1JoFpBpyg/UKL8FM5fk4I/AAAAAAAAKyI/bssSXO6W8i8/s640/IMG_0049.jpg

https://lh4.googleusercontent.com/-UOzY3x_hg1o/UKL8I8PCgCI/AAAAAAAAKyA/3EXOirEu_PE/s512/IMG_0051.jpg

The zero problem is sort of complicated. If I touch the Zero Plate to the aligator clip the Input 1 correctly lights up. The problem is when the connection is separated the light stays on. In order to turn the light off I have to trigger one of the proximity switches. I discovered tonight that if I press in the E-Stop switch the z-plate connection works correctly (light only turns on when the clip and plate touch).

Any suggestions on where to go next would be greatly appreciated.

[twelchPTM]

what you have there appeara to be a shopbot buddy prs standard. I don't know if touching the plate to the clip is the right way to test the plate. When our bot was set up we were shown to connect the alligator clip to ground and then touch the plate to the bit.(This may be the same thing but I'm not sure). Also it would seem to me that the wiring for the z plate could fine and the wiring for your e-stop could be the problem. have you considered that maybe the previously educator intentionally wired the machine so the e-stop had to be in in order to use the zero plate?
Just shooting off some initial thoughts...I will look more closely at my connections when i get in to the shop tomorrow

[Brady Watson]

The wiring and action you describe appear correct. There are 3 Zzero plate wires in the cable - Black, Green & Red. These correlate to Input 1, Ground and 5v+ respectively.

The only thing that the Zzero/Input 1 is looking for is ground. It sends out a 5v TTL logic signal and lights up when a ground closes the loop. The Gnd can be the alligator clip OR any metal bolt on the machine that has continuity with the machine ground. So if the plate rests on a bolt or other bare metal part when it is in its holster, it can make Input 1 light up. A piece of electrical tape can fix that - just insulate where the plate touches metal.

Since you have a router with brushes that wear & break continuity with the main shaft of the router & body, you need to use the clip on the collet nut or bit in conjunction with the Zzero plate.

Your tool is a BT32 'Buddy' with 4G controls - so if you visit ShopBotDocs.com, you can look up the 4G board and check the correct wiring config to verify that your wiring is correct.

-B

[Educator]

I wish my issue was just a matter of the cable touching a ground. It the light for input one lights up and stays lit after touching the zero-plate to the alligator clip. The light goes off (or clears) after I trigger one of the proximity sensors.

I have confirmed that all of my wiring to the board is correct. I have also confirmed that the board itself is functioning properly (via a small jumper wire). Aside from replacing the individual wires one at a time do I have any other options?

Thanks.

[Brady Watson]

You can try to reload the firmware via the UI command in SB3. Download the latest version of the control software v3.6.44 and then load the firmware for it. If this does not fix it, you have 2 choices.

First, if the Zzero plate is working and the only thing going on is that the light stays on - then you can keep rolling with it. If the Zzero plate does not work after doing a C2 for a second time, then it is staying toggled on & that would point to a faulty controller card. The only other option would have is to send the card off to ShopBot for evaluation. You should call SB and see if there is a solution to your problem if you have already downloaded the latest software and the issue persists.

-B

[garyc]

Andy...
It sounds as though you have some of the input (prox and zzero) wiring crossed up. Maybe even tied into the estop circuit or input 4.

Take and post a pic that shows clearly the blue block connectors for inputs 1 thru 8 and the color of wires that go to them. Also, look carefully for any errant strands of wire that jump from one terminal to the next. It will help if the text on the board is right side up, so us ol guys can read it!

Once posted we can show you which wire(s) to change.

[Educator]

I have discovered that if the X and Y proximity switches are NOT grounded the Zero-Plate and Aligator clip function perfectly. If I ground the X and Y proximity switches (i.e. the Blue Cables) the Zero issue remains.

I can only have the X and Y switches work OR the Z-Plate.

I hope that some one is smart enough to deduce why this would be.

Thanks in advance,

Andy

[Educator]

I have confirmed, with the help of a representative, that all of the wiring is correct. I have gone over the diagram and confirmed proper wiring twice now. The representative also confirmed that the motherboard is functioning properly too.

I updated the firmware and that changed nothing.

Does the grounding issue make any sense to any one?

I am getting ready to spend the remaining grant money allocated to my program and I am seriously reconsidering any more ShopBot machines.

Please help.

-Andy

[jerry_stanek]

Try moving the ground wire from the z plate to a different pin on the board I had a faulty ground for my z plate and that cleared it up

[Educator]

I tried a different ground with no avail. Any other suggestions? What else can I check I am desperate.

Thanks again,

Andy

[garyc]

Andy...
Have you spoken with ShopBot Support? They will have a method to diagnose the problem.

[jerry_stanek]

did you do a ur command and reload your firmware

[gene]

have you done a continuity check on the wiring to the plate and clip to make sure that there is no short