laser 4000 arch turns too early

[waright]

2 experienced carwash operators are stumped. Laser 4000, virtual treadle, latest version vt. Every once in a while our laser will be coming across the rear of a vehicle, drivers side towards pass. side, and stop in the middle of the car and turn the arch. bridge goes fwd and get an arch impact error. We have replaced picket fence prox and right limit prox and both cords. we have tried spare wires in the festoon and have ran separate shielded wires back to the bay jbox. We have bypassed the terminal strip connections in the trolley box. Every time we make a change we think we have it solved, but to no avail. We removed the drivers side picket fence and still get this error (was concerned about vt board not hiding input from picket fence prox).

I believe it always happens on the first pass of presoak. if it makes it the first time without turning early, then it seems to always complete the wash. The trolley is always in the same spot when it turns. The picket fence prox is 2 to 3 "clicks" into the passenger side picket fence.

We are confident that the trolley is not skipping any of the picket fence counts. We have slowed the speed down to 0 on all passes. Tires, bearings, swivels are all good and proper. We have tested for voltage drop on the 24v dc xfmr. while the freq drive is running.

It can happen 7 washes in a row or it can be weeks between failures. When it is happening constantly, I haven't been able to see any inputs coming on out of their regular sequence.

Is it only the right limit that can stop the trolley?

PDQ has been good to talk to, but we haven't pinpointed the issue yet.

 

[washnvac]

Since it is always the first pass, is it possible your passenger side ultrasonic is not measuring properly? Or it needs a re-calibration? This would make it turn early. If your count and right limit are definitely working, isn't the ultrasonic measurment the only thing that would tell it that it is across the rear of the car, and to turn? When this happens, where is the arch when it starts soap at the right front of the car?

Just thinking out loud here.

 

[waright]

do you know if I can unhook the sOnars and run the wash that way for a while. I know it would run side limit to side limit but that way I can verify if it is a sonar issue Thanks

 

[PEI]

If you unhook a sonar from the VT board it should go to the limit on just that side.

 

[Scottc186]

I have the same problem. Did you ever find out what it was?

 

[waright]

issue is still not resolved. This unit has the old style blue ultrasonics, so we have ordered the new style black ones. will probably get them on this weekend and will run for a couple of weeks. will post and let you know.

 

[Scottc186]

Thanks for the update! We are going to try new pickets (a couple of the pickets are rusted through) and also the wago in the j1 box is very corroded. If those don't work we're replacing the festoons. I will also keep you posted in my progress !
Scott

 

[waright]

the new black ultrasonics fixed the problem 1 month now and no shutdowns. thanks for the input

 

[Scottc186]

Glad to hear your up and running! I'm still down. New vt, all new trolley rollers, tires, prox., all new festoons. New ultrasonics all to no effect.
I either still get an impact at the rear center of the car or if that doesn't happen the arm goes to the right t bar and gets stuck. I then get an arch rotate fail. I'm done dumping money into this. I'm getting a price for a razor on Monday.