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How can static electricity shocks from treadmill be prevented?

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rehud
#1
Dec25-06, 10:09 AM
P: 5
At the small gym I am working at there are about 12 treadmills. On some of them if you run for a few minutes and then touch the body of the treadmill you get a static electricity shocks. The machines are all properly grounded.

At first, I thought the problem was that the body of the machine is not grounded properly (meaning the standard grounding is not grounding the body). Then I thought this may not be the case at all; I think the problem is that runner is not normally grounded to the body, and now I see two general ways to prevent the shocks:
1. Increase the room humidity to prevent the static electricity load from building.
2. Somehow ground between the body of the runner and the body of the mechine.

Does anyone know how to solve that problem? Have any experience with that? Have any feasible idea how to do that?

Thanks,

Ehud
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marcusl
#2
Dec25-06, 12:03 PM
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If you want to ground yourself to the machine, you can try the wrist straps used by electronics workers to protect against static buildup when they work with microchips. It is a little black velcro wrist strap that has a light coil cord attached (like the ones you sometimes see in grocery stores that hold pens, except this one has a wire inside). You'll have to figure a way to attach the cord to a metal part of the machine. Maybe you could use another wrist strap?
rehud
#3
Dec25-06, 12:34 PM
P: 5
Thanks Marcus!
Well, this is a feasible idea.
Actually I thought about something similar (without all the technical details, which are important), but the problem is that not many people would really like to use something like that. Many treadmills already have some kind of a strap that actually looks almost the same but has a different purpose - one can attach it to his/her body or cloth somehow and then if s/he happens to slip or the treadmill is too fast for him/her this strap is being pulled and the treadmill stops instantly.
The problem with that is that it is not very comfortable or maybe it does not look very cool; anyway, people do not use it. Hence, I do not think they will like the anti-static strap better.
I am trying to find some sort of idea that would not cause any mechanical inconvenience to the runner. Maybe I should have explained that before.

Ehud

AlephZero
#4
Dec25-06, 03:20 PM
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How can static electricity shocks from treadmill be prevented?

I guess if the treadmill "belt" is a good insulator, the thing could work the same way as a Van der Graf generator.

If that's the case, the fix is probably to select the right sort of cleaning fluid. We once had terrible problems with static electricity in an building with vinyl tiled floors, when the cleaners changed the stuff they put in their mechanical floor polishers. When they changed back the the old product, no more shocks.
Astronuc
#5
Dec25-06, 07:57 PM
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The machines are all properly grounded.
The machines may be properly grounded, i.e. the metal and electrical systems may be grounded, but the rubber tread is a good insulator and the static charge may build up because the tread itself is not grounded.

marcusl's proposal would work and is used as indicated. In addition, there should be metal wire brush similar to those used on some printing machines which allow for static discharge. I imagine it is the rubbing of rubber or synthetics on the rubber or nylon treadmill that produces the static charge.

Changing the materials or spraying a mist of water or anti-static material would probably also work.
russ_watters
#6
Dec26-06, 12:13 AM
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A metal mesh in the belt would probably help by allowing the belt to actually be grounded.

Random anecdote:

I used to belong to an LA Fitness that had crappy, old machines and one treadmill I used had a problem where whenever you touched the metal heart-rate sensors and shocked it, it would reset the machine. While I'm running, I rarely touch the machine, and just swinging my arms, I'll hit it every now and then. It was more of an annoyance than anything, except every now and then, the machine would get fried and not reset.
rehud
#7
Dec26-06, 03:19 AM
P: 5
I am really grateful for all those answers!

Quote Quote by AlephZero View Post
I guess if the treadmill "belt" is a good insulator, the thing could work the same way as a Van der Graf generator.

If that's the case, the fix is probably to select the right sort of cleaning fluid. We once had terrible problems with static electricity in an building with vinyl tiled floors, when the cleaners changed the stuff they put in their mechanical floor polishers. When they changed back the the old product, no more shocks.
Well, changing the cleaning fluid seems really feasible. Two questions I would ask:
First, do you think such material should be used under the "belt" to improve the conductance with the machine, or above the belt to improve the conductance with the shoes? (Actually, this is asking where do you think the problem is?)
Second, what kind of material/fluid should be used? Names of chemicals would be more helpful than trademarks, since trademarks changes from country to country and I am far from the US and Europe.

Quote Quote by Astronuc View Post
In addition, there should be metal wire brush similar to those used on some printing machines which allow for static discharge.
What you are actually saying with that is that you believe the charge is being build between the "belt" and the machine body. I was thinking before of using something similar to those "brushes" some cars are carrying on their rear bottom to discharge static charges to the road. What you are saying is that something like that also exist on printing machine. Do you (or anyone) have any idea if there is some standard "brush" of this kind that may be bought somehow? Does anyone have any experience with something similar on a treadmill?

Quote Quote by russ_watters View Post
A metal mesh in the belt would probably help by allowing the belt to actually be grounded.
Well, this seems like a good idea for the treadmill manufacturer. I am not sure how can one do that without the manufacturer help, which may be to hard to get.
3trQN
#8
Dec26-06, 09:13 AM
P: 349
Either eliminate friction or earth the parts.

I would use a drag strip similar to a cars earth strip, a small flexible and replaceable strip that hangs and makes contact with the body of the treadmill (which is earthed) to ground the running surface.

EDIT: pfft just read above posters reply :s :)
Prof_LarGo
#9
Jan12-07, 09:46 AM
P: 3
I eliminated static shocks by wearing different running sneakers. (after I paid a lot of money for them)
rdt2
#10
Jan20-07, 07:46 AM
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I haven't bothered looking for a solution to what is a minor irritation. I wonder whether the static build-up decreases as sweat dampens you and your clothing.
Prof_LarGo
#11
Jan24-07, 10:50 AM
P: 3
Alot of what your saying is probably correct, plus friction caused by the running shoes will create the shocks. However, I am sure that the material of the sneakers, such as the nylon used, increase the presence of static shock.
chemisttree
#12
Feb1-07, 03:44 PM
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Dust could be building up between the belt and the rollers/treadplate. I may go away after removing the belt for a thorough cleaning and relube. Waxes are sometime used as lube but a little graphite might help conduct the electricity from the belt to the treadplate.

IT may go away!

(Apparently I'm already gone...)
Prof_LarGo
#13
Feb2-07, 09:16 AM
P: 3
The belt I have is new and clean, and the static shocks are quite shocking! I even tried to ground myself, with a wire from the treadmill to me-and shocks came every 4 seconds. Needless to say, I threw away the wire. Would a single surge protector help? I'm curious , and will purchase one. Stay tuned.
EngrMHKhan
#14
Dec24-09, 07:42 AM
P: 1
Hi there,

We are facing the same problem.

I think it is due to dryness of the belt rubber and the plactic on which the belt moves. So clean it up and use Silicone oil spray. This is the only solution we have not yet tried! So lets do it and share the results.
DrZoidberg
#15
Dec27-09, 06:30 AM
P: 385
Simply spray the belt with anti static spray.
You can make your own quite easily.
http://www.firehow.com/200912196243/...tic-spray.html

Or just mix some fabric softener into the cleaning fluid when cleaning the belt.
minger
#16
Dec27-09, 10:53 AM
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Quote Quote by russ_watters View Post
I used had a problem where whenever you touched the metal heart-rate sensors and shocked it, it would reset the machine.
I have the same problem. I swear last week during a good run I felt a home electrical plug amount of juice.

I haven't bothered looking for a solution to what is a minor irritation. I wonder whether the static build-up decreases as sweat dampens you and your clothing.
Doesn't seem to help me.

I'd be interested in a decent solution to this problem. The last thing you want is yet another reason to not go to the gym.
MacLaddy
#17
Jan8-10, 05:49 AM
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Not sure if you are still looking for a solution to this, but I have a couple. I also work maintenance at a health club, and we have this problem on occasion.

Typically the problem is from Life Fitness Treadmills, but I have seen different brands do it on occasion. The most common occurrence is that this part has failed, or been removed.

http://www.sportsmith.net/ItemForm.a...01OK2617640000

I've never used that particular website, but it is the correct part for this machine. That anti-static tinsel line just crosses the striding belt directly under the treadmill, effectively channeling the static off of it.

Another common problem can be that the motors are not properly grounded. If you are getting shocked often then I would recommend adding an additional ground wire to the motor.

Hope those suggestions are helpful.

Mac
jbrunner61
#18
Jan13-10, 01:38 PM
P: 1
Hi All,

All the answers were certainly worth looking at but I have found a sure-fire answer, although it may need to be repeated a couple times during the dryer winter months.

Mix 1/2 oz of Downy fabric softener with approximately a quart of water into a clean spray bottle and shake. Spray a coat of this solution on TOP of the belt. . . yes, the black walking surface. I then use a damp cloth to even it all out, then let dry.

Once dry, your electric shock SHOULD be gone. Give it a try, I think you'll be surprised!


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