Listen, I drive firetrucks, ambulances, and dump trucks every day. What you are seeing are onspots. A lot of times departments will take off the onspots in the non snowing months to eliminate the noise and avoid corrosion. That's why you might not see them except for in the winter.

Anyway when they are off, we don't drag anything else or something like that for grounding. It's just not an issue. Like I said, our ladder truck has 10 radial tires and they are the only things that touch the ground. We have no radio/grounding problems. On the rest of the trucks, we don't have any grounding/radio problems when the onspots aren't on.

I also checked to see if ours drag. They BARELY clear the ground on flat and level ground. That's with dual rear wheels. Any bump or anything could cause them to scrape.

Mike

 

would something like that wear rather quickly?

 

Ok, lets see if we can get this straight...

- In my opinion, what was spotted was most likley on spot chains
- I've never seen chains (on spot or otherwise) used for grounding.
- On spot chains are not intended to serve any purpose other than traction - except maybe to spawn endless threads on truck forums.

But that doesn't mean that certain vehicles don't have grounding issues and a need to discharge electrical potential in a safe manner. Traction and grounding are two different issues, not to be confused with one another.

 

Not if its bearly touching the ground.


Ok folks....now what about the southern states that doesn't get alot of snow? :0

 

I have seen them on all the school buses around here in Northern Virginia.

Mike D.

 

Did they appear to look like this ?

http://www.eurekaboy.com/brmc/onspot.htm

 

ICY ROADS!!!!

 

VEHICLE GROUND STRAP
"Maintains Electrical Connection to Ground"

Like a Grounding Wrist Strap for your car! No one likes that awful big shock when getting out of an automobile or truck. That shock is the discharge of "chassis voltage" built up as the vehicle moves along the highway. What you might not know is that in addition to causing symptoms of high body voltage in the driver and passengers (such as fatigue, irritability, drowsiness, and motion sickness), this type of discharge causes serious injury when it occurs at the gas pump. Every year, this seemingly innocent spark occurs at the wrong place and the wrong time: igniting gasoline vapors while fueling the vehicle. This is prevented by grounding the vehicle.

The Vehicle Ground Strap can be used on any car or truck. Simply affix the strap's clamp to the chassis of the vehicle and allow the conductive strap to dangle to the ground. Safe, durable and unaffected by the weather, the Vehicle Ground Strap maintains a secure ground and electrically neutral vehicle. Makes a great gift too. 18" long, 1 year warranty.

Vehicle Ground Strap (Cat. #A214) ……… $19.95

http://www.berk.com/~lessemf/personal.html

Before straps like this were available it was not unusual to see a chain hanging down from tankers and fuel trucks.

 

It's being marketed as a personal EMF shielding device.

Wow, maybe we could electrically energize concrete and start running cars off of electricity as they drive down the road. Unfreakin' believable.

 

yup, they work almost as good as deer whistles.

i have been driving trucks for 30 years, and NEVER, EVER had a chain dragging on the ground under the truck, NEVER, EVER saw a chain dragging under a truck, AND ANY COP I KNOW WOULD PULL OVER A TRUCK DRAGGING A CHAIN ON THE GROUND, especially A TRUCK WITH A FLAMABLE MATERIALS PLACARD!!!!
that is almost like asking the vilage idiot to use a flare for light to see if the tank is full.

 

... so that means it was never, never, ever ever couldn't possibly have been ever been done? Hardly. There are a lot of things that are done normally and customarily right now that will be as big, or bigger a "NO-NO" in the future. Dumping chemical waste in landfills ... spraying waste oil on roadways ... smoking tobacco products ... for that matter there weren't many placards displayed back then. At most the word FLAMMABLE was painted on the body along with the other lettering.

My Dad drove a fuel truck back in the fifties. The chain ( a light weight one sometimes with a little wire on the end) wasn't set up to drag, only touch the ground when the vehicle was stopped. Obviously your knowlege is much more encompassing than my memory. Now put down your flare

 

And please tell me what the ground potential of asphalt is. I'll tell you its not very good unless its wet out. It's just another gimick like the Tornado.

 

I see... Over-Unnecessary use of the QUOTE feature.

How about addressing the post with the persons name ...rather than use the quote feature with pictures in it?

A rubber ground strap attached to a car is a given for static arrest.
Until I put a ground strap in the car,Nichelle & I alwys got a shock when we were getting out of the car


The Chain (s) I really have seen the odd the truck with a single chain that occaisonally touches the ground while the vehicle is moving.

What else would that be for ?

Killing bugs ?

 

"My Dad drove a fuel truck back in the fifties. The chain ( a light weight one sometimes with a little wire on the end) wasn't set up to drag, only touch the ground when the vehicle was stopped. Obviously your knowlege is much more encompassing than my memory. Now put down your flare"

ClydeSDale,
yes there were lots of people that once dragged chains behind gasoline trucks. I've seen them myself and was told in the 70's that they were there for grounding the truck so that it would prevent a fire due to static. We have learned something since the 70's and now know that a chain will not dissipate static nor will it provide a ground.

Static is the build up of an electrical charge on something such as a truck that could provide the source of ignition for a flammable vapor atmosphere. Static is typically created when the vehicle is driven or when a rubber hose is connected to the truck and fluid is either pumped into or from the tanker. In the case of pumping fluid, a bond wire connects the frame of the truck to the pump which is in turn grounded by connecting a wire from the pump to a copper rod driven into the ground about 8 feet deep. In most cases a static discharge inside the tank of a gasoline tanker will not cause an explosion because the gasoline vapors are too rich inside the tank to burn, however, a bond wire is required as a precaution. In any event, a bond wire electrically bonds different objects such that there is no electrical potential difference between the two objects, therefore an electrical discharge does not take place. A ground wire is a copper wire connected to a copper rod driven into the ground to provide a means of taking an electrical potential and sending it to the ground in a safe manner as opposed to sending it through a person's body.

 

We run about a 2 foot piece of log chain on the back axles of our combines. It takes away the static electricity and keep the dust from clinging to the windows as bad.