DC clamp meter opening size

[rslaback]

I'm interested in picking up a clamp meter capable of sensing DC draws to use for parasitic draw testing on my cars. I am noticing that a lot of the clamps that I see pros use on YouTube University are a small clamp roughly the size of a battery cable. I see meters with that size clamp available in listings and also some that have a more standard clamp like the AC meter I have that is designed to get around a home service cable.

Is there any accuracy difference between a large clamp and a small clamp dc meter?

 

[HenryAZ]

Individual parasitic draws will not register accurately on a clamp meter, as they are usually <1amp, and a clamp meter will typically read to 1 decimal point, if that. This is where you use the current measuring feature of your DMM, which is usually limited/fused for 10amps, and has different current ranges to pick up small draws.

 

[rlitman]

A standard clamp meter will not have the sensitivity to see a small DC parasitic load. A good 600A clamp meter may read 0.1 amps, but is hardly trustworthy below 2A. It just won't cut it. Those clamp meters with the thin elongated clamps are milliamp clamp meters, and they're designed for just this task. The long probes aren't necessary, but they make it easier to pick out a single wire in a harness.

 

[MattGarage]

I have an ac/dc clone clamp meter from Amazon. It helped me find and fix a battery drain issue with an RV. It is extremely useful.

Very often I'd prefer a smaller clamp. The larger one is good for where space is available abut I was renovating a vintage guitar amp recently and wanted to check some currents and it was useless for that.

Not much help to your initial question but something worth knowing in advance.

 

[uncwstudent]

Im similarly confused with clamp meters and automotive work.

Would a Brymen BM079 or Matco MD79 clamp meter work? They measure DC current from 10mA-600A.

 

[2ndGearRubber]

Im similarly confused with clamp meters and automotive work.

Would a Brymen BM079 or Matco MD79 clamp meter work? They measure DC current from 10mA-600A.

That would work for a a main battery cable to ballpark charging current.

The jaws are too large and even smaller clamps are too inaccurate for parasitic draws. Unless it's a massive 1+ amp draw. The clamps will drift away from their zero point.

The big value for current measurement is with an oscilloscope.

 

[ronkz650]

The Uni-T UT210E clamp meter is low priced at $45 or so, and does the job pretty admirably. I can read current down in the 20ma range. Sure beats breaking the circuit to insert an Amp meter.

 

[uncwstudent]

That would work for a a main battery cable to ballpark charging current.

The jaws are too large and even smaller clamps are too inaccurate for parasitic draws. Unless it's a massive 1+ amp draw. The clamps will drift away from their zero point.

The big value for current measurement is with an oscilloscope.

Good info. I didnt know that. Thanks for the help!

 

[rslaback]

So I decided to roll the dice on an eBay meter. It had good reviews at a 50 dollar price tag. The ebay seller had no idea how to answer my question about if it could sense DC amperage but for 15 bucks I gave it a go.

So far, so good.