Sweep Drift

[nick300_us]

I have a problem that maybe someone has come a cross before. I have 82/70's with mp chassis. I have a problem with a few machines. I've try to solve this problem on one machine. When you get to the machine the sweep will be a gaurd you push the swrs switch and the sweep will go to home. I've changed the sweep micro switch assy all new micro switches. Still does it once in awhile. This afternoon I swapped the complete mp chassis with the machine next to it. The league started bowling and it happened again on the same machine. If anyone can help me with this it would be great.

[keeth]

Nick,just wanted to clear up a couple of things here. SWRS if that is sweep reverse,it would never do anything by itself it needs the sweep run also. If you meant sweep run by that and the sweep is at guard 2 this is what 1 machine has done to me. The sweep would get to guard 2 and crawl backwards enough to unclick the micro and then the sweep would not go home because it was not getting the guard 2 signal anymore and hitting sweep run would send it home. It turns out my gearbox was too loose. If this is your scenario try swapping out your sweep gearbox to see if it goes away.

[Scooter185]

The machine is going through a cycle, first or second ball it doesn't matter, and after completing the cycle the sweep is running down to first guard and sitting there. So we use SWRS to clear it.

[keeth]

Scooter,A score correction must be done also each time?

[Jan-Willem]

What type of motors, if they are nationals change the carbon brush. Is the sweep indeed going up home and drops back. Important to know

[mardigras]

Check the C1 plug to machine and see if you have any burnt sockets. Also see if you have any capacitors shorting out. I have had the sweep do that when the CSM2 was shorting out. it would work a little then sweep would drift. This causes not to brake properly.

[Scooter185]

Keeth, no we don't have to correct the score

Lane, we run Westinghouse gearboxes

[keeth]

Normally if the sweep goes up then back down it will re-shoot the pic and score,are you really sure that it does up then down? I am not questioning your smarts at all

[Scooter185]

I was wrong it does score, oops

[spanner8270]

Scooter, quite literally it could be any or a combination of the things suggest here, however my bet would be on a failing micro switch not stopping the sweep at zero coupled with a gearbox that has lost its bearing pre-load or a failing capacitor that is not giving the correct electrical braking if the switch causes a delay at zero. As its scoring,, its passing zero and then activating the scoring micro it does seem like overrun, can be helped with a drag brake on the motor shaft - this is not cure but a bandaid untill you get to the root of the problem.

[maister]

I reckon spanner8270 is correct by suggesting a combination of things. I would suggest you isolate one at a time.
Firstly the chassis, this would check if it was a contactor problem, then check for sticky micro switches or worn activation bolts or weak springs on the micro SA ,SB. weak capacitors. loose motor gearbox. or something under the box beam cover shorting out on the terminal tag strip which vibrates and sometimes will cause it.
These are the areas I would initially suspect.
good luck.
maister

[nick300_us]

I just figured I would let everyone know what I found as the cause of my problem with the sweep drifting. I went in to work this morning and the only thing I didn't change was csm #1. I changed csm #1 started the machine and the sweep stops on a dime. There's no visual signs of arcing or any cracks anywhere. When you test the capacitor with a meter it checks okay. Problem solved.