Products > Test Equipment
Good clamp meter for low DC currents
(1/15) > >>
ElectricPower:
Just wonder witch clamp meter i should buy if my main usage was to measure low DC currents in mA and uA with highest possible accuracy?

Is the EEVblog BM036 a good coice? Or can i buy something cheaper?
wasedadoc:
Measuring such low dc currents with a clamp meter is prone to large errors.  The device is essentially measuring measurement magnetic field.  The wanted component is produced by the current you are trying to measure.  But other unwanted components come from the earth's magnetic field and other objects such as your screwdrivers, metal toolchest, vehicle engine and bodywork etc.  When set to measure dc current, clamp meters have a 'zero' button to null those out but the slightest movement of the meter changes those unwanted components and gives an error in your reading.

You can make the wanted field stronger if it is possible to have multiple turns of the wire passing through the clamp.  You then need to scale down the reading it gives you.
DaneLaw:
What's your budget as it gets expensive fast if you want uA-clamp measurement ability?
uA in DC clamp regi?  gonna be a challenge to clean out for your "highest possible accuracy" and not drift.

I recall the UnitT 211B and the corresponding mocked-up Extech M63 can do uA on the clamp, but usually only in AC where they can muster 0.1mA resolution
An overall decent cheap AC&DC clamp meter for milliamp is the old UT210E, though not sure what they are going for here in late 2023 or if there are better alternatives for the price, as the UT210E got quite a few years/decade under its belly.. - many alternative models will nowadays do DC 1mA clamp measurement and quite a bit cheaper with dual display (freq) and higher native display count.

Previously the UT210E was around 30 to 35US delivered.. - for that price it's a decent low current (1mA res) DC clamp meter, but you will cycle that zero-button to the cows come home when pursuing DC readings down to the last mA to keep these hall sensors in check.

--- End quote ---

--- End quote ---
Martin72:
Hi,


--- Quote ---Is the EEVblog BM036 a good coice?
--- End quote ---

Lowest range is 60A....

A current clamp meter that can measure mA accourate is not cheap and cannot be cheap.
We (work) bought one from Benning to be able to measure standby currents.
We have it calibrated regularly and the accuracy is good.
But it is very sensitive, the maximum currents must not be exceeded, it can only measure up to 10A.
But it can also measure mA.

Benning CM11
J-R:
Many clamp meters can measure uA through the test leads albeit with a pretty hefty voltage drop.  The BM036 does not have this uA feature, but the BM037 does.  However, the clamp is not going to give you any usable mA capabilities.

When I was searching for a DC mA clamp back in the day I settled on the Fluke 771.  It has 0.01mA resolution at the lowest range and can measure up to 110mA.  They are readily available on the second hand market.  0.01mA accuracy is possible with some care, 0.1mA is pretty easy and 1mA is basically guaranteed no matter the conditions.  However, it's very limited otherwise.  It's really made for a specific purpose (4-20mA loop signals).

Instead, could you make some kind of resistor shunt test fixture that could be easily inserted into your circuit?
Navigation
Message Index
Next page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod