Radius issue - Arm rotating randomly and hitting car.

[Car_Wash_Guy]

Second time this has happened.

1st time the arm rotated as if it was clear of the drivers front fender, but was really in the middle of the vehicle, and proceeded to go up and over the vehicle ( shouldn't there be a sensor to stop the wash if it detects the arm is pivoted/bent?). This happened about a month ago.

2nd time ( yesterday ) arm rotated after the gantry traveled rearwards down the drivers side of a vehicle ( truck again ), and rotated as if it were clear of the rear of the vehicle at about just in front of the rear wheel.

Any ideas? The randomness of the occurrences is puzzling.

 

[MGSMN]

"1st time" - Inspect the trolley belts for slack or missing teeth and the drive pulley for wear. Make sure the keystock has not worked its way out of the drive pulley. Adjust or replace the arm tilt prox switch. This issue could also be a bad boom wire.

"2nd time" - Inspect the gantry belts for slack or missing teeth and the drive pulley for wear. Adjust or replace the wheel count prox switch and check that wheel bearing. This issue could also be a bad boom wire.

 

[slash007]

I had the same exact issue. After replacing prox switches and ultrasonics and all kinds of other random stuff, turned out it was a broken boom wire. It was making and breaking depending and having issues when it went back further for longer cars. Was able to bypass the bad wire using a spare, but after using 2 spares, eventually just replaced the whole boom wire and it fixed everything.

 

[Ryko CS]

In both situations, it depends "when" these happened in the cycle. If they were in the first pass of presoak, the machine is basically using the readings from the ultrasonics to map the vehicle. If it were in one of the subsequent passes, it's more likely mechanical or a prox.

In the first situation, if it is in first presoak, it's more likely left ultrasonic or a boom wire not transmitting signal. If in subsequent pass, it's all timing (it drives for X seconds based on calculations from the ultrasonic in the mapping pass), so more likely a trolley belt loose. There is a tilt prox whose signal should have been lost if it were to make contact with a vehicle.

For the second situation, this sounds like a rear ultrasonic or boom cable if it's in first pass of presoak. If it were in subsequent passes, I'd lean more towards the count prox or target, loose gantry drive belts or a wheel bearing being bad.

 

[Waxman]

I have a different machine but I would suspect a bad wire. your machine is receiving a signal that says rotate. if the proxes are good, start looking at wires.