Gear Review Anyone ever figured out how to test a buried magnetic vehicle sensor?

New guy here and long time geek... I've never encountered the issue I'm having with my Dakota Alert in all my years of electronics and computers. Dakota support says that the probe should read 800-1000 ohms on the two leads when disconnected from the sensing receiver/transmitter.

It does that, but what they weren't able to tell me was how I would be able to test the device when a vehicle is passing by.

Hopefully one of you folks have encountered this issue.

Many thanks,
Nick

 

I had to look up Dakota Alert to see what the system was all about.

Wouldn't the simple solution be to monitor the system while the IS a vehicle passing by?

My next couple questions would be, can it detect mostly alloy motorcycles, and very tall off-road vehicles? I have magnetic sensors at the traffic light out onto the highway that will not detect most bikes and will NEVER change for tall military vehicles. I have to drive around convoys occasionally, park my car, walk over to the lead vehicle and climb up to explain the problem to the driver. This was safer when I was still on active duty and in uniform. I have to be cautious on my approach nowadays. We usually arrange for road guards to be deployed to stop traffic while the convoy clears the light.

How about if it's found out? Can someone disable or confuse your system with something like sprinkled iron filings from a brake lathe? (Great bulk source of raw material for making iron oxide... but I wouldn't know what you'd want to use that for. )

 

It works on inductive change.
Take a reading without a vehicle, then have someone drive over it.
There should be some observable change as long as you have a meter that isn't junk.

 

I have been told a coiled up extension cord plugged into itself will trick a sensor.

I never bothered to test it.

 

I always tested drive through sensors with a hand truck parked on them.

 

When you put a large metallic mass, say something made mostly of steel near a coil of wire it changes its inductance.
This will increase the resistance if you put a meter on it.

 

I always wondered what would happen if somebody spilled a bucket of steel shavings onto the road over one of these sensors and while trying to sweep them up, just managed to spread them around even more?

 

You know...hypothetically. Asking for a friend...

 

Tossing iron shaving near the inductive sensor will result in a one time change if it is enough to effect the sensor at all.
It might change the base line inductance a little.
Then next time a vehicle drives over it the coil will still register an induction change spike.
Just dirt in contact the the coil of wire compared to hanging in air will change its inductance. Dirt causes higher inductance, that's one of the reasons power transmission don't run under ground for long distance.
Virtually all of these sensors are dumb, they are just looking for a sudden change in the inductive loop.
Now in theory, you could have a smart sensor that tells you if there is a bicycle, motor cycle, car, truck, SUV, semi, armored and how many of each. Possible even detect of someone is trying to tamper with it.
But out side of. Gov and .mil customers looking for remote monitoring there isn't much application.

 

Hmmm. Every one I ever set up (hundreds) measured the change in capacitance.

 

hall type or ?? there are 3 types .
!!
@)!( = 2019 ,,
I know Im just pissing ya ,

OP has NOT listed year , etc , JUST guess

Waste of time!!/

Ask a real question with real info to report back !!
Kids !!


III'll start !!
KID

I have a ??????????????????????????????
Vin is
this is the problem !!!######################

If they can't decipher VIN , OUT

DUH
This is not hard !!

Im looking at a M3
Im a V1at ,
(not my area or world + )
TX was built in ,, Figured !

~~~~~~~~~~~~~~~~~~~~~~

PC kid Yur UP !!

ON your first POST !!

 

Sloth, I've been reading your posts for a while now and I don't have any idea what you want.

 

I attached a 16 lb lift magnet to the front forks of my motorcycle did the trick.