Laserwash 4000 sensor issue

[carwashspain]

I’m trying to learn about the 4000 which came with a site I just bought. I’ve been getting recurring Impact Switch Hit faults, but it’s not anything in the Troubleshooting guide, except maybe a faulty T-bar sensor. I’m wondering if I’m right in saying that the T-bar eyes/ sensors tell the machine that it’s reached either the back corner (ie:- halfway mark) or front corner (Home position) of the car and it’s time to turn? And if so is it the T-Bar STOP eyes? The problem is that the machine is stopping about a foot short of reaching either the back or the front of the vehicle, then turning and moving across like it HAS reached the back or front limit, and hitting the car (that generates the IMPACT SWITCH HIT fault). So it looks like the relevant sensor thinks it’s reached either the back corner or the Home Position corner, when it actually hasn’t. Is this correct or am I off track and it’s something else?

 

[Waxman]

on my old machine which was different from yours, the ultrasonic sensor measures the vehicle on the first pass. Then the information on distance is used by the wheel count proximity switch for all subsequent passes. Maybe the laser wash is the same. If so, I would check the wheel count Prox switch because you are losing some distance from the initial measurement if it does in fact Perform the first pass correctly.

 

[carwashspain]

on my old machine which was different from yours, the ultrasonic sensor measures the vehicle on the first pass. Then the information on distance is used by the wheel count proximity switch for all subsequent passes. Maybe the laser wash is the same. If so, I would check the wheel count Prox switch because you are losing some distance from the initial measurement if it does in fact Perform the first pass correctly.

Okay good point but there’s no mention in the manual of a wheel count prox switch (theres a diagram of all the switches and sensors), plus does the ultra sonic not just measure the width of the vehicle?

 

[bosswash]

If it’s stopping short, turning and then whacking a car, I would look at the T Bar eyes first. Look for a cracked one that might be getting moisture inside. It could also be a short in the festoon wire which can cause all kinds of gremlins.

There is no wheel count switch on the lw4000. Ultrasonics handle width measure only.

T bar eyes have emitters and receivers btw

 

[carwashspain]

Thanks for that, was focusing on the t bar eyes and going to change all four and see how I go.

 

[Zal]

If you don't have cameras in the bay, then go get some. You are hitting the cars with the spray arch and need to know exactly where this occurs. Many things enter in but don't be afraid to call PDQ tech line for help. No charge if you can provide the information needed. I would suggest you find a distributor to get you some help on this one.

 

[carwashspain]

Good advice, thank you.

 

[PEI]

The LW4000 finds the rear of the vehicle with both the exit end T-bar eyes and the mid limit. When the bridge starts to the rear of the vehicle, Output Y40 goes off and Output Y41 comes on. This switches power between the 2 sets of T-bar eyes. The A5000 begins looking for Inputs X21 and X26. Input X21 is for the T-bar eyes, this tells the A5000 that it has found the rear of the vehicle. If it has already seen Input X26, the Mid Limit, then it will turn and cross the rear of the vehicle. If it hasn't seen Input X26, then it will continue back until it does. It will go a set distance past the Mid Limit and turn crossing to the other side. This prevents the overhead from getting tied up.

The front of the vehicle is found the same way. The only difference is that Output Y41 goes off and Y40 comes on. If the A5000 saw a short vehicle while going to the rear it will compensate for Input X21 coming on immediately and wait to see it go off and then come back on. If it saw Input X26 before X21 while going to the rear then it just starts looking for Input X21.

Knowing this you can test the T-bar eyes by powering on Output Y40 and checking the Exit end T-bar eyes. Then powering off Output Y40 and powering on Output Y41 check the Entrance end T-bar eyes. Use 63556 to cut on the outputs.

 

[Zal]

Great explanation from PEI - you won't get any better advice than this.

 

[carwashspain]

The LW4000 finds the rear of the vehicle with both the exit end T-bar eyes and the mid limit. When the bridge starts to the rear of the vehicle, Output Y40 goes off and Output Y41 comes on. This switches power between the 2 sets of T-bar eyes. The A5000 begins looking for Inputs X21 and X26. Input X21 is for the T-bar eyes, this tells the A5000 that it has found the rear of the vehicle. If it has already seen Input X26, the Mid Limit, then it will turn and cross the rear of the vehicle. If it hasn't seen Input X26, then it will continue back until it does. It will go a set distance past the Mid Limit and turn crossing to the other side. This prevents the overhead from getting tied up.

The front of the vehicle is found the same way. The only difference is that Output Y41 goes off and Y40 comes on. If the A5000 saw a short vehicle while going to the rear it will compensate for Input X21 coming on immediately and wait to see it go off and then come back on. If it saw Input X26 before X21 while going to the rear then it just starts looking for Input X21.

Knowing this you can test the T-bar eyes by powering on Output Y40 and checking the Exit end T-bar eyes. Then powering off Output Y40 and powering on Output Y41 check the Entrance end T-bar eyes. Use 63556 to cut on the outputs.

Excellent, detailed response, much appreciated, have swapped out all t-bar eyes, but will be a few days until I can test it as have used the time to renovate the auto bay as well (much needed). Thanks again.