Bumper Car fire @ Carowinds

[Oldiesmann]

Relatively minor incident but still something you don't expect to see. https://www.wral.com/bumper-car-catches-fire-at-carowinds-park/17605410/

[IndyGuy4KI]

Glad no one was hurt. Never seen a dodgem catch fire.

[westcoaster]

Never seen this, glad there was nobody injured. 

[fyrfyter]

I’m shocked we haven’t seen this before. Bumper cars are usually DC powered. The floor is positive and the ceiling grid is negative, that’s why you see sparks when they move. One bad DC motor and voila!

[jcgoble3]

7 hours ago, fyrfyter said:

I’m shocked we haven’t seen this before. Bumper cars are usually DC powered. The floor is positive and the ceiling grid is negative, that’s why you see sparks when they move. One bad DC motor and voila!

Wait, the floor is electrified during the ride? I didn't know that.

[teenageninja]

8 hours ago, fyrfyter said:

I’m shocked we haven’t seen this before. Bumper cars are usually DC powered. The floor is positive and the ceiling grid is negative, that’s why you see sparks when they move. One bad DC motor and voila!

Are you sure?  I thought that the ceiling was positive and the floor was negative.  Seems like a huge safety issue if something went wrong and someone steps on a floor that should have been shut off.  Also, wouldn't you need to lock out and tag out to load and unload?

[fyrfyter]

Yes, I’m sure. Look at it the next time you get on. The ceiling is grounded to the buildings superstructure.

 

Yes the floor is electrified when the ride is going. If it’s flipped and the grid is electrified, it doesn’t matter. Rubber soles will protect you, as long as you don’t connect the grid with the floor. I’m guessing the system is 24-48VDC, and probably a couple hundred amps.

 

If you watch when they unload, they hit the Emergency stop then remove the keys from the control console. It doesn’t need to be locked/tagged out unless maintenance is going on.

 

 

 

[jcgoble3]

36 minutes ago, fyrfyter said:

Yes, I’m sure. Look at it the next time you get on. The ceiling is grounded to the buildings superstructure.

Yes the floor is electrified when the ride is going. If it’s flipped and the grid is electrified, it doesn’t matter. Rubber soles will protect you, as long as you don’t connect the grid with the floor. I’m guessing the system is 24-48VDC, and probably a couple hundred amps.

If you watch when they unload, they hit the Emergency stop then remove the keys from the control console. It doesn’t need to be locked/tagged out unless maintenance is going on.

So what would happen if a stupid guest (the kind we all know exist) just got out of the car during the ride? Or more to the topic of this thread, what if the fire occurred in the middle of the ride and the rider in that car scrambled out of the car before the operator noticed and could hit the e-stop button? What if said rider lost their flip-flop in the scramble to get out of the burning car and hit the electrified floor with their bare foot, or tripped over the side of the car and planted their hand/arm on the floor?

[fyrfyter]

So what would happen if a stupid guest (the kind we all know exist) just got out of the car during the ride? Or more to the topic of this thread, what if the fire occurred in the middle of the ride and the rider in that car scrambled out of the car before the operator noticed and could hit the e-stop button? What if said rider lost their flip-flop in the scramble to get out of the burning car and hit the electrified floor with their bare foot, or tripped over the side of the car and planted their hand/arm on the floor?

That would be nothing. If it’s a DC circuit, one side is positive one side is negative. The floor is either negative or positive, depending upon the article you read. Just standing on the floor even in bare feet when it’s charged won’t do anything. Now if you touch the grid, we get to see you become a glow worm.....

[TheRickster]

I wanna be a glow worm.

[malem]

These days, most bumper cars are set to a much lower voltage than was used historically.

[King Ding Dong]

This is why there is a 8’ 6” height limit on the ride.  

[teenageninja]

13 hours ago, fyrfyter said:

Yes, I’m sure. Look at it the next time you get on. The ceiling is grounded to the buildings superstructure.

 

Yes the floor is electrified when the ride is going. If it’s flipped and the grid is electrified, it doesn’t matter. Rubber soles will protect you, as long as you don’t connect the grid with the floor. I’m guessing the system is 24-48VDC, and probably a couple hundred amps.

 

If you watch when they unload, they hit the Emergency stop then remove the keys from the control console. It doesn’t need to be locked/tagged out unless maintenance is going on.

 

 

 

I'm well aware of the loading and unloading procedure, I've ran the ride.  It also isn't isolating the power source.  I think you are wrong, but unless we can get someone with a source it's all conjecture.

[fyrfyter]

I'm well aware of the loading and unloading procedure, I've ran the ride.  It also isn't isolating the power source.  I think you are wrong, but unless we can get someone with a source it's all conjecture.

They will allow you to operate a ride even if you don’t understand how it works?

That’s extremely worrisome. How can you tell if there’s a problem if there isn’t a PLC display to tell you there’s one?

[teenageninja]

4 hours ago, fyrfyter said:

 

They will allow you to operate a ride even if you don’t understand how it works?

That’s extremely worrisome. How can you tell if there’s a problem if there isn’t a PLC display to tell you there’s one?

 

I'm not sure what you are getting at, and I understand your background.

I've also been trained on Lock Out/Tag Out at numerous jobs.  By removing the key and hitting the emergency stop, you aren't completely isolating the energy.  Let's use an extreme example.  Someone leaves the key on the table, while they are walking around the floor, barefoot, someone starts the ride while they are touching one of the metal posts around the outside of the ride, zap.  If the ceiling is the ungrounded side, they would have to jump and touch the ceiling while being grounded.  Hence my statement.

The argument I am making, is that the floor is the GROUND and the grid on the ceiling is electrified.  Yes I understand with it being DC, it could work either way.

[fyrfyter]

An E-Stop is supposed to be a complete power cut. It’s supposed to isolate the device from operating. Lock outs are secondary devices so that it cannot be accidentally turned on. It’s a redundant system that usually is only used for emergencies or maintenance. They function like a secondary power switch between the source and the device, but ahead of the E-stop.

Knowing how to lock out/tag out is different from knowing how it works. It concerns me when it’s stated that an E-stop is not isolating as it should.

Gas pumps require an E-stop nearby. To eliminate confusion, it kills all the pumps not just one. I would expect rides to operate similarly.

Your example is employee error, not that the E-stop isn’t functioning correctly. A true non-functional E-stop example would be hitting the switch and it truly not completely disabling any function. This does not mean an immediate halt to any ride movement.

My point is, do they give ideas as how to tell when something isn’t operating correctly? Do they give training on what to look for in regards to ride malfunctions, or abnormal operating?

[teenageninja]

43 minutes ago, fyrfyter said:

An E-Stop is supposed to be a complete power cut. It’s supposed to isolate the device from operating. Lock outs are secondary devices so that it cannot be accidentally turned on. It’s a redundant system that usually is only used for emergencies or maintenance. They function like a secondary power switch between the source and the device, but ahead of the E-stop.

Knowing how to lock out/tag out is different from knowing how it works. It concerns me when it’s stated that an E-stop is not isolating as it should.

Gas pumps require an E-stop nearby. To eliminate confusion, it kills all the pumps not just one. I would expect rides to operate similarly.

Your example is employee error, not that the E-stop isn’t functioning correctly. A true non-functional E-stop example would be hitting the switch and it truly not completely disabling any function. This does not mean an immediate halt to any ride movement.

My point is, do they give ideas as how to tell when something isn’t operating correctly? Do they give training on what to look for in regards to ride malfunctions, or abnormal operating?

On CNC equipment and the tractors my company makes the E-Stop doesn't kill the power to the machine.  It prevents the controller from operating.  So I don't think your statement is 100% correct.  I don't 100% recall what the function of the E Stop on Dodgems is.  However, on Dodgems the operator leaves the booth to check seat belts on the cars.  What is preventing someone from turning the ride on while they are out doing it?  That would be what the Lock Out/ Tag Out would be for, to prevent someone from starting the ride while they are gone, however, most people at Kings Island aren't LOTO trained, so that point is irrelevant.

[TheRickster]

E-Stops just prevent the ride from functioning while it's pressed in and cut the power off at the control panel. (not at the main disconnect that would be used for lock out for maintenance /emergency purposes) Also at my time at the park we NEVER tagged out or locked out at control panels, the main disconnect was always thrown for the up-most safety.

No park trains ride operators on what to recognize if the ride isn't working right. There are an infinite number of things that a ride can do and they want them all pretty much reported if you're not sure about something. If you introduce training then the ride operator is making that decision on whether or not they feel it's serious enough to report. They typically want to track all things.

Also I believe teenageninja's point is that if the floor is the positive it's very easy for someone to simply ground themselves out vs the ceiling. If a guest were to simply touch the floor they are much more likely to be shocked if it was a positive vs a negative. The ceiling is typically seperated on it's own even using rubber bushings so it doesn't ground its self out before powering the cars.

Some research I also read the system is high voltage/low amperage and will also have breakers as an added safety feature as well.

 

The newer bumper cars that do not have a ceiling have a grid of positives and negatives on the floor that are spaced out. 

[IndyGuy4KI]

According to this reddit article the floor is negative and the ceiling is positive.

https://www.reddit.com/r/askscience/comments/3hlb3m/how_do_dodgem_bumper_cars_circuits_work/

This article shows the circuit also supporting the ceiling being positive.

http://bestonbumpercars.com/how-do-bumper-cars-work/