Grayhound Skill Crane - potentiometer ratings question

[BeTheClaw.com]

So what's the deal betheclaw.com? Are you just gonna go with a replacement board from
Scott?

If so how much is he gonna charge you?

Getting a spare set of 3 boards for $125... will be nice to be able to swap around for troubleshooting purposes.

[Metalman1661]

Very nice. I'm guessing you talked to Scott and he is selling them to you? If that is the case I will call him to see if he can sell me some replacements.

[BeTheClaw.com]

Yes, he said someone had emailed him and he replied.. not sure if it was you. But yea, may have to leave a message, but he called me back same day 

[Metalman1661]

Just an update to my situation:

I ordered one of every IC chip on the CPU board and they arrived the other day. I swapped out the Z80 CPU chip first since it was one of the few socketed chips on my board.

After swapping it out I turned the machine on and the revision codes flashed quick, '06 02 19 87' then the machine attempted to home it self. It began moving forward but when it reaches the front the limit switch clicks and it doesnt stop.

I tested the continuity of the front switch and the continuity from the switch down to the board and everything is making connection. I also checked continuity from the switch to the CPU board.

I decided to change the IC that controlled the crane limit switches. This IC was U9.

After replacing this IC the crane was homing correctly and the coin light and coin lockout would activate.

The machine coins up fine then while playing the crane would automatically go left. If I pressed right on the joystick the crane would automatically go back to the left upon release. After verifying the wiring I decided to replace the ICs which controlled the joystick inputs and crane motors. These ICs are U8 and U11. After replacing these ICs the crane was moving properly during play.

Now during play when I press the crane button the crane drops down but when it reaches the bottom of its movement the claws do not close. I tested the input line voltage to the board with the transformer on it and it read 115 V but I could not get a reading between the two white lines going to the solenoid.

Can you tell me the voltage of your 'white to white' wires going from that transformer board to the solenoid when the claw is moving up and returning home after grabbing a plush?

Thanks for the help.

[BeTheClaw.com]

Can you tell me the voltage of your 'white to white' wires going from that transformer board to the solenoid when the claw is moving up and returning home after grabbing a plush?

Wow... very impressive. I'm glad you were able to get it to work, mostly. I'll check it for you within the next day or so and let you know. Have you checked the voltage at the point where the black telephone handset style claw wire connects to the coil in the claw cylinder? That wire may have a break in it.

Update on my situation 

I ordered a complete set of boards, since I had 3 problems with my machine... First being a missing potentiometer, which made the claw insufficient in strength even at highest setting on the one existing pot. I swapped the claw board and now have much greater flexibility.

Second and third were intermittent issues were with right and left movement relays. Right one occasionally had hesitation after pressing the button, and left one sometimes wouldn't work at all. Replacing the board took care of both issues so far. I may consider sending the original board for repair down the road.

I have a need to replace the CPU board at this time. Unfortunately, the one I received doesn't have socketed chips, but I guess that's not a huge deal, since my original board has them and is working fine. Interestingly enough the non-socketed CPU board is revision 2, looks slightly different, and has an extra wire soldered to one of its corners. I'm going to email to find out what that is for.

[Metalman1661]

I put the multimeter leads on the white connector located on the transformer board and it read nothing. I will try to test continuity of the black stretchy coil wire later to see if there is a break. 

My CPU board is REV-2 also and the ICs are not socketed. As I replaced the ICs I added sockets so I can swap them out down the road if I need to. I will post a pic when I can.

Are you referring to the green wire located in the bottom left corner?

[BeTheClaw.com]

Are you referring to the green wire located in the bottom left corner?

Yeah.. this one:

[Metalman1661]

Yup thats the one I have too. Connect it to the FG terminal on the power supply:

[BeTheClaw.com]

Thanks!!! Looks like ground, I guess...

[BeTheClaw.com]

Can you tell me the voltage of your 'white to white' wires going from that transformer board to the solenoid when the claw is moving up and returning home after grabbing a plush?

Sorry, I tried, but for some reason, I'm only getting "1" on display of the multimeter. I have it set to 20VDC. Not sure if it needs to be something else, but according to the manual, good setting should put out around 12V.

On a side note, I got some claws from Rainbow to simulate a Sugarloaf Toy Shoppe crane. Quite fun

This is the largest one. I have a couple of smaller ones as well. One medium plush and one jewelry. The original Grayhound claw is way too small for my taste.

[lilshawn]

not 100% sure, but by the looks of that power supply board design, you might need to read AC not DC 

can't hurt to try it.

[BeTheClaw.com]

not 100% sure, but by the looks of that power supply board design, you might need to read AC not DC 

can't hurt to try it.

True.. but manual does say it needs to be set to VDC...

[Metalman1661]

Did you measure the voltage when the claw was closed/returning to home after a play? That should be the only time you will get a reading to the solenoid.

I looked up the datasheet for this transformer and it does say the secondary is in volts RMS although I distinctly remember measuring DC voltage across a resistor at some point.

I'm just a little lost on how I can test to see if my solenoid is bad or not or to see if that coiled wire is no good.

[BeTheClaw.com]

Yeah, it was reading 0 at idle, and 1.0 when claw was closed. Grayhound manual says you should aim to set the rear pot at 10V and then add 2V with the front one for a total of 12V. Are you not getting any reading at all from the white terminals? Maybe you could try measuring current into from the other two wires to make sure power is being supplied to the claw board in the first place. If you run out of options, I could send you my original board (temporarily) for testing purposes.

Allen

[Metalman1661]

I unplugged the terminal from the transformer board and measured voltage across the black and grey wires (AC input) and it read around 115 Vac so I know power is getting to the board.

Which manual are you using? I ask since the two manuals I have stats the voltage should be 0-30 Vdc or 10-25 Vdc.

Attached are the two manuals I have been looking through.

[BeTheClaw.com]

I unplugged the terminal from the transformer board and measured voltage across the black and grey wires (AC input) and it read around 115 Vac so I know power is getting to the board.

Which manual are you using? I ask since the two manuals I have stats the voltage should be 0-30 Vdc or 10-25 Vdc.

The 2nd manual, Grayhound_Crane_Schematics.pdf, on page 3 says to set the rear pot on 10 VDC and then add 2 on the front. Thanks for the supplement! That will come in handy someday.

[Metalman1661]

Gotcha. I also noticed we have different transformers on our boards. I'm referring to your old board. This may have been a reason why we had a different amount of components from each other.

It's interesting how the two manuals I attached to my previous post have different schematics for the claw power control boards. Also the supplement attachment goes over voltages at specific points in that circuit. Could be helpful to me.

Later today I will test the continuity of the coil and trace the power path through the circuit. Hopefully I will find a fault and fix the issue.

[BeTheClaw.com]

I also noticed we have different transformers on our boards. I'm referring to your old board. This may have been a reason why we had a different amount of components from each other.

Hmm.. really? They look the same to me 

[Metalman1661]

The model number on mine is "PC-40-600B28." Your model is "PC-28-800B52."

According to the datasheet I posted earlier they have the same output but are different.

EDIT - Actually after looking at the datasheet aain it says the secondary output for mine is around 40 V while yours is around 28 V.

Also I can confirm the output to the coil is DC since there is the bridge rectifier in the circuit directly after the transformer output. I totally forgot that was there haha.

I will post my finding later.

[BeTheClaw.com]

The model number on mine is "PC-40-600B28." Your model is "PC-28-800B52."

According to the datasheet I posted earlier they have the same output but are different.

Also I can confirm the output to the coil is DC since there is the bridge rectifier in the circuit directly after the transformer output. I totally forgot that was there haha.

I will post my finding later.

Ah.. yeah, not quite sure why I wasn't getting a reading on mine. I had the multimeter set as shown below... the only thing I can think of is that my black terminal is missing its end, so it's just bare wire, but I doubt that could make a difference.

[Metalman1661]

I see you have the red lead coming from the amperage terminal. To test voltage you must have the red lead coming from the Voltage terminal below that one. The black terminal is fine as well as the dial setting (20Vdc).

After swapping the terminal on the meter, measure the voltage drop across the two white wires (DC + and DC -). You should get a value as the claw closes (either positive or negative but the same number regardless)

If you connected the meter to the circuit as you described with the red lead in the amperage terminal I would expect the reading to be zero or close to it.

[BeTheClaw.com]

To test voltage you must have the red lead coming from the Voltage terminal below that one.

Ah... that explains it. I connected to the other one because it's labeled DC. I'll try it tonight 

[Metalman1661]

Ok so I tested continuity between the two input wire to the solenoid and I got nothing. I did get some beeping as I opened and closed te claws by hand.

I read the voltage drop across pin 1 and 2 on the transformer and it was only around 30 volts. I'm assuming that is since there is no load(the coil) on the secondary side.

Can you test a few things with your setup? Can you test the continuity of the claw coil? Also can you test the continuity between pins 1 and 2 of the transformer?

Did you manage to read the voltages?

[BeTheClaw.com]

Sorry,  not home right now. I don't usually get to play with it til after 9:30  Meanwhile, how exactly to check for continuity?

[Metalman1661]

Put the meter on continuity setting (looks like a sound symbol). Test to see if it works by touchin the two leads together , a beep should sound.

Touch the two input leads to the claw coil (on the white connector that starts the coiled wire". See if you have continuity.

On the transformer, touch pin 1 and pin 2 in the same matter (transformer labeled on the top). Does it beep?

[BeTheClaw.com]

Put the meter on continuity setting (looks like a sound symbol). Test to see if it works by touchin the two leads together , a beep should sound.

Touch the two input leads to the claw coil (on the white connector that starts the coiled wire". See if you have continuity.

On the transformer, touch pin 1 and pin 2 in the same matter (transformer labeled on the top). Does it beep?

My meter doesn't beep for some reason.. but when it's set to the continuity, it shows 1. When I touch the wires, the number starts fluctuating, which I guess is an indication of continuity. That said, there's definitely fluctuation of numbers between transformer pins 1 and 2, and the two wires of the coil...which I assume means continuity. And for the life of me, still can't get a voltage reading to the claw. I actually had the red lead connected to the other port (not how I showed it in the picture). And that's the one that gives me a reading of 1 or less. When connected to the other port (like in the picture), no reading at all.

[Metalman1661]

OK.

I figured the coil of the claw (solenoid) would have continuity from one lead to the other since it is just a coil. Mine does not however and I thought possibly the coil was not good.

Similar situation with my transformer. pins 1 and 2 are the two input pins for the primary side o the transformer (primary coil). I think this may be due to the transformer is in the circuit though.

It would be great to have a spare transformer board that I know works.

[BeTheClaw.com]

It would be great to have a spare transformer board that I know works.

You're welcome to borrow my claw board. If you have Paypal and can send me $35, I will mail the board to you. You can test with it and send it back for a refund (minus $5-$6 for shipping), or you can just keep it for parts if you'd like. It it's the one with a single pot. I was told it was made that way. It works fine with the Grayhound claw. (I had to get a 2-pot board because I replaced my claw with another and needed more flexibility with adjustments)