(Topic ID: 150615)

KS relay not working right

By Grangeomatic

8 years ago

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#1 8 years ago

I’ve got a Ship Ahoy that I’m working on, but this really could apply to just about anything with a mini-stepper. I’ve taken the KS relay apart, cleaned it, lubed it, adjusted the alternating switch for minimal tension, and now it seems to operate very well, if not perfectly, when I’ve got it on my bench. I’ve cleaned the Jones connector pins.

My problem is that when it’s in the game, it doesn’t work properly. On this game, when you shoot the spinner, it applies power to this KS mini-stepper, so every revolution, this should energize and upon de-energizing, it should step. There is also a “spinner relay” that is in parallel with the KS relay. The problem is that when that spinner switch closes, the stepper doesn’t always really energize (but the spinner relay in parallel with it is practically “chattering”, just as expected with a good spinner shot). If I manually work the spinner slowly and measure the voltage on the coil for the KS relay, I can see that there is voltage to the coil, but the armature plate doesn’t always pull in right away. There is sometimes a delay and then eventually, it will pull in. Once it pulls it, it will step flawlessly, but on a good spinner shot, it sometimes doesn’t react fast enough to advance. On this game, that means the yellow lights on the wheel don’t appear to be spinning around the wheel like they’re supposed to.

What would cause the armature plate on that stepper relay to be so sluggish?

#2 8 years ago

How far away is the armature from the coil? That distance is also adjustable.

#3 8 years ago

Hi Jeff
in the schema (Your pin) in the list of relays / coils: Does Gottlieb say "KS-Relay is a "AS"-type relay. A snippet of the schema with that Relay and the "Spinner-Relay" would be nice (to see). You did not write about - do You know the section "Gottlieb's AS Relay (the Miniature Stepper)" ? Here: http://www.pinrepair.com/em/index2.htm#emsteppersvideo - but move upwards half a page - they have some good information to AS Relay. I have never taken apart such a thing.
Greetings Rolf

#4 8 years ago

Dirtflipper, can you explain how to adjust the distance? I've had the thing apart a couple of times, but don't recall seeing that. Is it related to the part that is in between the two main plates, that gets attached by one screw on each side, allowing it to "pivot" between the plates? If so, I have fiddled with that to try and get it closer, with no luck. If there's something else, I'm all ears.

Rolf, you know, I have read through those repair guides many times through the years, but somehow missed this section on the AS relay. Good info. I'll have to get a snippet of the schematic later, as I'm currently at work.

#5 8 years ago
Quoted from Grangeomatic:

Is it related to the part that is in between the two main plates, that gets attached by one screw on each side, allowing it to "pivot" between the plates?

yes - that can tip down so that the armature plate doesn't come back up so far away from the coil, so the coil doesn't have to work as hard pulling the plate down. You loosen the screws, tip it down, then tighten them again.

#6 8 years ago

and then there could be magnetization in the armature slowing down the release

#7 8 years ago

Hi Jeff
the reason I ask for a snippet of schema - Your: "The Spinner Relay is in parallel with the KS-Relay". I have an Orbit and a Surf Champ - both with a spinner and an "advancing unit" - NOT beeing mounted TRUE parallel. So I'd like to see this part of Your schema.

TRUE parallel: ONE Switch lets current flow to BOTH of Your things.
Pseudo-parallel (I just created this word): A Relay-QQQ is activated -> this relay has TWO switches -> one of these switches activates the Spinner-Relay - the second switch activates the KS-Unit. As the Relay-QQQ flatters: Both units should act unisono - but "what is --- when one of the switches is dirty / oxidated" ? Greetings Rolf

#8 8 years ago

DirtFlipper, I'll take a look at that adjustment, but I thought I had it down as far as it would go. Much further and it won't be able to release up high enough, I'm afraid.

Pinhead52, the release doesn't seem to be a problem. It's the actual activation of the plate, not the release.

Rolf, I've attached a pic of that part of my schematic. They are in true parallel. The P relay and the KS relay are both powered by the spinner switch. The P relay works as it should. The KS doesn't like to pull in some of the time.

I'm going to double check the voltage on the coil of that KS relay. Perhaps I'm losing something on one of the bottom panel Jones plugs...


#9 8 years ago

Hi Jeff
in post-1 You write: "the KS-Stepper doesn't always really energize ... sometimes a delay and then, eventually it will pull in".
Thanks for the snippet of schema - TRUE parallel (mounted) - is the Spinner-Relay mounted at the underneath-side of the playfield AND the KS-Stepper is mounted in the cabinet ? Or is the KS-Stepper mounted in the Backbox ? If so: there will be a loooong wire and there is a Jones-Plug in that wire (we might want to take-Out the playfield - so we have Jones Plugs) - is this Jones-Plug CLEAN ?

Want to do a test to tell "electrical problem <-> mechanical problem" ? Take TWO Jumper-Wires and REALLY MAKE PARALLEL CONNECTION(S). If Your problem still exist: Must be mechanical. If Your problem disappeared: Electrical problem.
Set one Jumper-Wire: Connect "Lug on Coil-KS-Stepper-Side-Wire-Black" <-> "Lug on Coil-Spinner-Relay-Side-Wire-Black".
Set the second Jumper-Wire: Connect the other two Lugs of the two Coils (in Your snippet of schema I read / guess: Wire-Color-Brown (?)).
Greetings Rolf

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