The machine belongs to a customer and so a photo won't be forthcoming very soon. It's just a wire; one end attached to one of the screws on the ramp motor bracket, the other end soldered to the power ground on the node board. To be thorough I probably should have added another from the drum motor but didn't think of it at the time. Just throwing stuff at the wall to see what sticks. Plus the driver chip datasheet suggests grounding the motors to PCB ground.

I have not seen a post where only the drum was plugged in. In post #78 and #79 above, he states the ramp was disabled, but it's clearly still connected in the photo. A stepper motor is often powered constantly to keep it from moving. Based on posts in the Owner's thread, the ramp won't stay up on its own without power. You can't progress through the game if the ramp isn't raised. I am assuming that if you disable the ramp in software, it is still moved and held in the raised position which requires power to the motor. Someone correct me if I am wrong about the software setting. I don't have a machine here to look at.

Premium
Plays: 1,905
Build date: early 2022
Code 1.02

Ramp died in December. Distributor submitted order to Stern for node 10 board on 12/20. Checked in with support yesterday and received this:

“The entire warehouse is currently doing inventory, and all shipping is on pause until this process is complete.  Once inventory has been completed, they will continue shipping out orders.”

Sounds like the limits of machine and man are currently strained. Apologies, just couldn’t resist... Hope the info helps!

Then wouldn’t the ramp lower when the game is powered off or unplugged if the motor is required to keep it up?

You'd have to clarify that with Spectrum-1980s as to what was actually connected when it blew or if the photograph is of the last node board. I'd assume he meant the motor connectors at the ramp were unplugged ?

The owners that have had to carry on with the board blown have propped the ramp up with either a small block or a sponge.

The ramp does need a holding current running through the motor or it will get knocked down by balls hitting the blue rubbers.

So, just to keep this going along the ESD theory as the fault taking out the regulator, what are the opinions of what could be the generator for the spike voltage ?

I've never really considered it before, but now you've put the seed in my mind I believe it could be well worth investigating.

What are your opinions on the connector shaft in the ramp from the motor. That is made of some type of polymer / plastic that I'm ready to believe could be the part that is 'possibly' the instigator ?

The other possible static generation location is where the finger hand comes through the clock drum plastic housing. They definitely rub against each other.

The ball hits the ramp and pushes the ramp down. During normal gameplay after the ramp is raised, a reduced amount of power is constantly running through the motor to hold it in position. The same is true for flippers. Full power is used to move the flipper, but when it reaches the up position, the power is reduced to hold the flipper up.

This whole node 10 situation seems very similar to the Wizard of Oz version 1 lighting issue back in 2013. At the time static discharge was suspected for blowing the output drivers of the light boards. I believe there are static fields built up between the ball and the playfield or maybe the ball creates a static charge between the top and undersides of the playfield (the playfield acting as a capacitor). I'm definitely not an expert when it comes to static charge. I know how to protect against it when designing a circuit, but I don't understand how it's generated in a playfield. I remember talking to Frank, the JJP tech support back then, and he was suggesting that certain playfield waxes would solve the issue. Some machines had no problems, others had perpetual problems (same as Rush). It was very difficult to nail down. Over a couple of years JJP tried various design changes to the light boards and finally scrapped that lighting system and replaced it with the 2.0 system.

What could be more worrying is if it's somehow connected with the Time Machine magnet creating some kind of static when the ball is passing through it. That in turn is getting dumped into the ramp ???

Stern replied that they have received the three node boards I sent back to them: two were their boards, one was from PBL. They seemed a bit surprised that only one board had visible burn damage, even though all three boards failed. Anyhow, the engineering team is going through them with a fine toothed comb.

Static buildup on the PF...that varies by the kind of wax used?
Someone was blowing smoke at you.
That isn't either science or engineering. It's baloney.

I can't review the entire circuit but the first thing I would look for is reverse EMP; same as when a coil's magnetic field collapses. Standard protection for that situation is a snubbing diode.
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Chris Hibler - CARGPB #31
http://www.ChrisHiblerPinball.com/Contact
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Highly doubtful. This is what Stern would call a fine toothed comb.

images (resized).jpg

That's the story so far.

Upvoted for this

I have been scratching my head, wondering why they went with a stepper motor for the ramp in the first place.

The ramp is either up or down, so it seems like a job for a normal solenoid.

Was it just because the board could control two steppers?

You're misinterpreting what I'm saying. The comment was just anecdotal and I took it as nothing more than that.

You can't use a snubbing diode on something that is essentially an AC circuit.

Apologies.
No offense intended to you.

True about the snubbing diode in an AC circuit. This motor drive is driving a DC circuit, isn’t it? I assumed so but might be wrong.
—
Chris Hibler - CARGPB #31
Http://chrishiblerpinball.com/contact
Thank you for checking out the PinWiki - http://www.PinWiki.com/

The 4-wire motors are bi-polar, meaning the coils have to have their polarity switched (basically AC performed by the chip). Unipolar motors (6-wire motors), such as used in Sega's Independence Day, can be driven like solenoids and could use snubber diodes.

Quoted from Wikipedia (https://en.wikipedia.org/wiki/Stepper_motor#Bipolar_motors):
"Bipolar motors have a pair of single winding connections per phase. The current in a winding needs to be reversed in order to reverse a magnetic pole, so the driving circuit must be more complicated, typically with an H-bridge arrangement (however there are several off-the-shelf driver chips available to make this a simple affair). There are two leads per phase, none is common.

"A typical driving pattern for a two coil bipolar stepper motor would be: A+ B+ A− B−. I.e. drive coil A with positive current, then remove current from coil A; then drive coil B with positive current, then remove current from coil B; then drive coil A with negative current (flipping polarity by switching the wires e.g. with an H bridge), then remove current from coil A; then drive coil B with negative current (again flipping polarity same as coil A); the cycle is complete and begins anew. "

Then what do you need to do to stop power to the ramp motor and lock it out like a pro?

Can anyone clarify the type and size of crimp connector used in this block ( 48v Power ).

Thanks,

Screenshot 2023-01-15 at 20.01.15 (resized).png

Molex(or similar) 5position .156” kk connector and pins.

Thanks,

LE
1215 plays since March 20, 2022
No Node 10 failures
I don't want to pop the hood to see what's underneath - afraid I'll jinx it.

Premium
Build date: April 25, 2022
Lifetime plays: 408
Total balls played: 1213
50 hours total "on time" (game is normally turned off after playing, aside from league nights)

No Node 10 issues as of yet. However, QR reader was defective upon delivery and replaced early on.

Wires connectors inspected around 200 plays. Last night I removed the clock, removed/replaced all zip ties, and checked wiring to motor. Zip ties were definitely tighter than they should have been, but insulation was not compromised, wires appear to be relatively fine.

Screenshot_20230115_000300 (resized).jpg

30-Plays- Node-10 not found, Inspected all wires, I just don’t see anything wrong/loose/etc. This has been extremely frustrating, Thanks for a new Node Board Stern, will just blow again until other parts are changed. April -2022, I posted in the Owners thread, I want all new part’s associated with node-10. It’s probably the clock or ramp motor and all the wires in between!!! Da!!

Smart move to be proactive with this machine. I agree that the super tight zip ties are quite prevalent. Whoever was working the Rush zip tie station in the late Spring/Summer season has some serious anger management issues.

Yeah, being complacent with that wiring is not a good idea. Looks like people have had their boards blow after even 1200 plays- remove any possible issues if you can.

It doesn't take long to pull the clock and inspect/replace those zip ties- 15 minutes if you have your toolbox nearby. Then inspecting the motor harness and replacing those zip ties is another 15 minutes. Well worth the piece of mind....

How many Lucky RUSH owners do we have in our special club? Is there a way display a running count?

I don’t know why these failures are happening but I am highly skeptical that Ip ties on wire bundles are the issue.
—
Chris Hibler - CARGPB #31
Http://chrishiblerpinball.com/contact
Thank you for checking out the PinWiki - http://www.PinWiki.com/

Same here -- has anyone found scorch marks on any perceived insulation wear spots? Or on a connector pin, from disconnects due to a wire being pulled on, bad crimp or no?

I'm assuming no, we would have seen pics. At any rate, it is highly unlikely that tight zip ties would lead to so many failures, but only on Node 10.

There were some photos in the main thread where they had actually penetrated and rubbed off insulation of multiple wires in the bundle,
likely causing direct shorts. Other photos in the main thread showed the wires severely mangled, from being over choked by those zip ties.

That is part of the reason why this thread was created, and, it may indeed just be because of those damaged harnesses.

Here's some examples I found from perusing the last few pages of photos from topic gallery. There's plenty more....

Screenshot_20230116_105543 (resized).jpgScreenshot_20230116_105721 (resized).jpgScreenshot_20230116_105743 (resized).jpg

Screenshot_20230116_105913 (resized).jpg

Again, no scorches, and squashed but unbreached insulation is still insulation. (Not saying it would necessarily scorch in the case of failure, but those are motor power wires...)

Also, not every failure game had evidence of this.

Look at the pics again- one clearly shows breached insulation. Some of the severely mangled wires could surely be severed underneath the insulation, and creating an EMF spike when losing continuity. Again, feel free to go through the photo gallery in the main thread, there's more. I just posted a few examples. I've been following that thread since the beginning, and have seen all posts and photos.

metal-mods can you link the main thread please?
—
Chris Hibler - CARGPB #31
Http://chrishiblerpinball.com/contact
Thank you for checking out the PinWiki - http://www.PinWiki.com/

Is Stern asking for the broken node boards to be returned to them now for examination? When mine failed and was replaced under warranty I specifically asked about return shipping for the broken board and they told me to throw it away. I decided to just save it in case it can be used in someway.

They want them back. I asked for a return shipping label and they emailed me one. Won't cost you a thing to ship back.

Just to be clear, the last pic in your example(solo wire laying on Golden Tee control panel), is not of any wire relating to the clock/ramp/Node issue. It was a different wire that got snipped on accident, while removing other zip ties, during investigation of the other wire bundles. Ask me how I know
It has since been replaced, and all is well.

Hahaha, ok, good to know on that one. Picture has been notated to avoid any confusion.

OK, questions relating to the Node 10 board. Godzilla uses these, correct? Has anyone been hearing/seeing any failures in GZ with these? I haven’t come across any posts mentioning it, but I also don’t really follow much GZ related.

Asking, as I know the end item affected, is the Node board. But if GZ is using the same board, it’s hard to believe it’s an issue with the board itself. What are the differences in use on GZ?

I’ve seen more than enough posts of “I got my replacement board, and it lasted X games.” Which makes sense, if the board itself is not the issue.

Like others, I’m dumbfounded that the resolution has been 100% figured out yet.

Godzilla uses same board. The problem is not the board. Stern knows this. Problem seems to be power interruption, possibly coming from ramp stepper motor area. However with this game, there also is an issue with extremely tight zip ties that may be contributing to the power interruption, thus causing the node 10 board to go into automatic meltdown.

We have a gz and I read the thread daily. To my knowledge, no #10 issues on GZ

Thanks. I also asked the Godzilla community on their thread.

Soooo, @Gandamack-

You've had multiple blown boards. Have your harnesses to clock and motor from Node 10 board been replaced? Or the clock motor? Or the ramp motor? Or has stern just been throwing Node 10 boards at you? Are there any batch numbers on any of these Node 10 PCBs? I didn't remember to check when I was replacing the zip ties.

Eventually, Stern grew tired of sending me just node boards. Upon my last blown node board they are sending me new clock and ramp motors and harness and..... another node board. It will probably be an epic wait time as the communication goes Stern then to distrubutor and then back to Stern for part number verification and then it is the weekend again and then there is are emails saying things like, "we dont have a part number for that....". Anyhow, the wheels are in motion and all I can do is wait.