Taking OHM readings
Taking OHM readings
(OP)
I learned a valuable lesson the other day. I'm not electrical but work with many issues related to it.
We have a submersible motor we use and it requires
that we take ohm readings to checkt the integrity of
the moisture sensors. I'm suppose to get 330k ohm
with a +/- 10% variance. Within that range the
sensors are working within acceptable parameters.
But periodically I get in a rush and can't find my
clamps so I will hold the red and black leads in my
hands (acting like a clamp) against the two leads on
the sensors. Well I got a low reading of about 279k.
So I called the motor engineering center to ask about
this reading.
He said not to hold the leads with my fingers as this
would give me a low reading since it would be going
through my body. Do you guys agree? Not that I'm
second guessing this guy but I just thought I toss
this out to see if other's have experienced this as
well.
It may make a good Helpful Tip to put out. It's so
simple that anyone could make this mistake.
We have a submersible motor we use and it requires
that we take ohm readings to checkt the integrity of
the moisture sensors. I'm suppose to get 330k ohm
with a +/- 10% variance. Within that range the
sensors are working within acceptable parameters.
But periodically I get in a rush and can't find my
clamps so I will hold the red and black leads in my
hands (acting like a clamp) against the two leads on
the sensors. Well I got a low reading of about 279k.
So I called the motor engineering center to ask about
this reading.
He said not to hold the leads with my fingers as this
would give me a low reading since it would be going
through my body. Do you guys agree? Not that I'm
second guessing this guy but I just thought I toss
this out to see if other's have experienced this as
well.
It may make a good Helpful Tip to put out. It's so
simple that anyone could make this mistake.
Wayne E. Lovison
service-parts@naglepumps.com





RE: Taking OHM readings
RE: Taking OHM readings
Experiment a bit and prove or disprove to yourself the accuracy of the support guy's statement. It will make a lot more sense if you do.
RE: Taking OHM readings
Spend $45 and got the correct leads and clamps. What a diffrence. The readings went right where they were suppose to be.
I needed 330K Ohm and holding by my hands I only got 279K.
Put the clamps on and I got 356K right in the ball park or spread of the tolerance.
It was well worth it and like I said someone should write a Tip for others to pick up this little tid bit of importance.
Thanks Again Guys
Wayne E. Lovison
service-parts@naglepumps.com
RE: Taking OHM readings
RE: Taking OHM readings
RE: Taking OHM readings
As for the ohm-meter, it's something almost every electrical student has done at home or in lab. Then only times I've used finger pressure is on items where there was mechanical difficulties, like light bulbs, where I either cared only about open/short conditions or knew that the parallel resistance was too low to be impacted by my body resistance.
TTFN
RE: Taking OHM readings
RE: Taking OHM readings