Grayling, MI
...but a reboot will bring it back to full power.
Any ideas?
(Topic ID: 120484)
There is no switching on or off of the 50v. It comes in as AC. Hits a fuse. to the bridge rectifier. Probably a cap in there too.
I would be looking for a physical connection issue. Like the fuse clip or the ac input plug. Attach an alligator clip to you DMM and monitor the 50v line. Fuss around moving the harness and what not, see if it drops out.
Quoted from G-P-E:Sounds like a fading or overheating diode.
The solenoid diodes don't ever get hot though? They are not under a constant load like the feature lamps or unregulated logic.
Just looked at a pictured of a RD white star driver board. There is all individual diodes to make the bridges. Give a visual check and a voltage drop check for anything that stands out.
Fuse clips? I had a RD board were one or two fuse clips were very loose and when pushing down on the fuse the clip just fell apart. Might be worth checking stuff simple as that.
Quoted from barakandl:The solenoid diodes don't ever get hot though? They are not under a constant load like the feature lamps or unregulated logic.
Just looked at a pictured of a RD white star driver board. There is all individual diodes to make the bridges. Give a visual check and a voltage drop check for anything that stands out.
Yeah, that's the theory.... diodes with intermittent use shouldn't heat up. But he has something that is dying over time. That is indicative of over heating. Only things in line -- connectors, fuse clips (which you already mentioned) plus diodes. One of them three is the problem. A defective diode with a high Vf will heat up quickly even with intermittent load.
... wonder what brand fuse clips are being used. I have seen lots of mentions of bad fuse clips. Cheap Chinese stuff?
Quoted from G-P-E:... wonder what brand fuse clips are being used. I have seen lots of mentions of bad fuse clips. Cheap Chinese stuff?
My only experience with RD boards is from one that came with a Data East machine. Two sets of fuse clips had to be replaced.. one was completely hosed (all bent out and fuse was loose in there) and pressing down on it further just broke them off. Not like it looked heat-damaged or anything like that. Also replaced another set just because one side of that set bent out when I pressed down on it.
No name on the fuse clips, so my thought was generic/imported stuff. I replaced with Bussman clips. IMO not an area to try to try to save a few cents. Okay, maybe a buck or two.. but still.
2 months later
Thanks for the help so far, guys. This issue is really weird.
Here's what is known.
When the power decides to die during a game, the lamp matrix, the coils and the switch matrix all go dead at once.
Testing the driver board at the test points after the game goes down, shows all of the voltages to be fine... but the 50v test point comes in at around 77v. It is 77v when the game is fully working too.
Resetting the CPU via the reset switch doesn't resolve the issue. The CPU reboots, and the coils, switch matrix and lamps are still not functional.
A full power reset via the power switch brings everything back to functionality.
Does that seem like something might be going on with the ground?
Quoted from tamoore:Thanks for the help so far, guys. This issue is really weird.
Here's what is known.
When the power decides to die during a game, the lamp matrix, the coils and the switch matrix all go dead at once.
Testing the driver board at the test points after the game goes down, shows all of the voltages to be fine... but the 50v test point comes in at around 77v. It is 77v when the game is fully working too.
Resetting the CPU via the reset switch doesn't resolve the issue. The CPU reboots, and the coils, switch matrix and lamps are still not functional.
A full power reset via the power switch brings everything back to functionality.
Does that seem like something might be going on with the ground?
+75V is normal for the high powered coils. I'm guessing that WS is White Star?
Without looking at the schematic, typically, the coils, switch and lamp matrices are on separate circuits. You just can't run +50VDC through the switch and lamp matrices. You'll toast other components on the CPU.
You also indicate that all of the voltages text fine on the driver test points. Have you checked the appropriate connector pins where the power leaves the board?
At first you indicated that the +50V dies randomly and in you last post you indicated that the switch and lamp matrices don't function either. It could be a logic issue and not necessarily on the driver board.
Thanks for the reply,
Yes, the story has changed over time, only because I'm noticing more and more things each time this happens. WS is white star. I'm starting to think it isn't the driver board either. However, a reset of the logic doesn't rectify the issue - only a reset/power down of the driver board.
Quoted from tamoore:Thanks for the reply,
Yes, the story has changed over time, only because I'm noticing more and more things each time this happens. WS is white star. I'm starting to think it isn't the driver board either. However, a reset of the logic doesn't rectify the issue - only a reset/power down of the driver board.
Pushing that button is not going to fix a flakey IC or bad data cable. Just saying.
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