Chassis issue

[cdsand5]

I have 1 ss chassis that just now decided to start running on its own. The sweep will run as if the sweep run switch is engaged, the table will run when it wants to with the spot solenoid being energized. Problem is in the chassis and I have swapped out all 3 ice cube relays and the OT board with the same issue. Ideas? My mind is on overload the last week along with me being down sick for 4 days and I am not thinking too clearly at the moment.

[Nev]

Run you hand thought the ball sensor
We have had this caused by A sticky Relay in the "F"Box

[Tablejam]

How would the FBOX cause.....

..
a continuous sweep run when it can only start a cycle as far as the sweep is concerned

...
cause the table to spot let alone run at all when the FBOX has no control over the table itself


I'm wondering if something is going on with the heat sink/varistors under T1 or if something fell in there causing in intermittent ground to the sweep and table contactor coils causing them to pull in.

[Stoctster]

^ +1 to Tablejam's advice - first thing would be to check the heat sink and wiring, may have something in there causing funny problems; sounds like the contactor coils are energizing at random. I'd suggest having a close look at the pins and sockets on C1/C2A, especially for any that have pushed through (or even touching due to a bad terminal block/wires touching at the rear of the plugs). Also check the slots on the motherboard (where the OT board plugs in) for any broken contacts - seems unlikely but it's worth a look. If everything seems ok I'd suspect a faulty contactor, most likely for the sweep.

[Nev]

How would the FBOX cause.....

..
a continuous sweep run when it can only start a cycle as far as the sweep is concerned

...
cause the table to spot let alone run at all when the FBOX has no control over the table itself


I'm wondering if something is going on with the heat sink/varistors under T1 or if something fell in there causing in intermittent ground to the sweep and table contactor coils causing them to pull in.

Opps Sorry thought He ment it was cycling by itself (red face)

[mechanic8230]

Yep. Like Tablejam said. Look for a contactor screw that came loose and fell down and is inbetween the heat sink and the chassis wall. I have had that happen to me before.

[cdsand5]

I did find a small piece of the mounting ear off the xformer behind the heat sink and removed it. The chassis worked for 6 frames then started acting up again. I just got off the phone with Jamie at Stahls and he told me to clip off the varistors so I did, problem solved. He is da chit.