<opinion>Lots of not so good advice on this forum regarding WPC resets and the daughter board.</opinion>
Test the voltage without load and with load. This will allow you to see if there's something (a load) dragging down the supply. ALWAYS test and measure WITHOUT the daughter board in the system. It is an additional variable that you must eliminate to get the cause of your issues. It causes "interference".
For the answer to this, you will need to ask the manufacturer of the daughter board.
Quoted from wastedthelight:TP1(12v)-12.6v
TP2(5v)-4.9v
TP6(50v)-66.1v (51 when solenoid fires)
TP3(12v)-10.8-11.2 fluctuating
TP8(18v)-14.2-15.5 fluctuating
TP7(20v)-14.1
See https://www.pinwiki.com/wiki/index.php/Williams_WPC#LEDs_and_test_points_on_WPC-089_Power.2FDriver_Boards for more detailed information on the test points. This should apply to the RD board.
Almost everybody on this forum mixes and confuses the "12V" supplies. Very, very common to see this with bad advice given related to it. I have written the follow a few times on this forum (other threads not this one). Seems to fall on blind eyes.
- TP1 = +12VU. This is UNREGULATED. Typically, unrelated to digital logic (+5VR) resets.
- TP2 = +5VR. This is output from the 5V regulator. On your RD board this is the small "vertical" board just above the test point rack. This is a highly efficient switching regulator. +4.9VDC is low but acceptable.
- TP3 = +12VR. This is REGULATED. Used by the switch matrix comparators on the CPU board. Also used by the daughter board as the "12V" source that it uses to generate the +5VR for the CPU board.
- TP6 = +50V. Solenoid power. Unregulated. Nominally 51VAC which is ~+70VDC RMS.
- TP7 = +20V. Flasher power. Unregulated. Nominally 16VAC which is ~+22VDC RMS.
- TP8 = +18V. Controlled lamp (matrix) power. Unregulated. Nominally 13.3VAC which is ~19VDC RMS.
Your voltages appear low. Check your line voltage (wall outlet voltage). Also check the VAC entering J101, J102 and J112.
I suspect you are not measuring the VAC correctly. Are you measuring this as VDC?
Quoted from wastedthelight:Here's an interesting kicker, I removed the WPC Reset daughter board and now the every few second resets stopped.I can actually play the game! I'm assuming this means that my 12v is still an issue since the daughter board uses the 12v to create a "better' 5v...so my problem is just hidden at the moment.
This is THE fundamental issue with the daughter board. It MASKS other problems on your power board. This is why I never recommend long term use of this board. It is useful to get yourself out of a mess in a pinch (operating a machine and need to keep it running) but it is not a long term solution. This daughter board, of course, only works as a solution if your +12VR is good. If the +12VR is failing then it won't help you. Always fix your power board. Don't use a band aid.
Quoted from wastedthelight:This is my findings so far after making it down to "6.18.12 Using a Multimeter to Test the Bridge Rectifier and Capacitors" of the reset troubleshooting guide. The capacitors are the large 5 black ones, right? Where's "BR2"? Not seeing a marking on the board and looks different than the guide, likely due to this being a Rottendog board.[quoted image]
The RD board replaced the bridge rectifier (BR2) with discrete diodes. They should be D51-D54. All the corresponding bridge rectifiers are "X1-X4" where X is the voltage.
- 51-54=5V
- 121-124=12V(U)
- 181-184 = 18V
- 201-204=20V
- 501-504=50V
Since the board is new, it should work. However, two things come to mind.
- RD is known for very poor quality assurance. Occasionally, someone becomes the unintended victim of this poor quality assurance.
- If you have had electrical problems, you may have damaged your power board. I do not have any evidence for this.
The one thing almost everybody NEVER mentions is your CONNECTORS. You "replaced" the headers when you purchased a new board but you didn't replace the connectors. This is why you measure the board without load. You want to know what the board produces as a baseline. Then you measure the voltage at the CPU board to see if your connectors have increased resistance and are reducing the voltage along the way.
In my experience, replacing the headers and connectors fixes most every WPC reset. Not all but most. I recommend you replace (re-pin) your connectors. If the connector at the power board (J114) is in poor condition, the daughter board will be receiving a reduced voltage that will cause it to indicate "low voltage".
The above might seem very strongly opinionated (and considered "tough love"). Your right to think that. Your right to ignore it as well. However, I didn't just spend one hour typing all that text for my benefit.