DC clamp meter

Estragon

So I got my new clamp meter:
https://www.amazon.ca/gp/aw/d/B0166GK8Q2/ref=mp_s_a_1_1?ie=UTF8&qid=1527080621&sr=8-1&pi=AC_SX236_SY340_FMwebp_QL65&keywords=ut203&dpPl=1&dpID=41LRqdsC1GL&ref=plSrch

The instructions are only in Chinese, so not especially helpful.  Maybe some out there has one and can help me in using it properly for measuring DC current.

It has 3 buttons; Select, Rel (delta symbol?), and Hold.  Select appears to toggle AC and DC when the dial is set to 40A or 400A for current measurement.  I assume the Rel button is used to zero it before clamping a conductor, and Hold is to keep the reading while unclamping?  It's mainly the zeroing process I'm not quite sure of.

littleharbor2

I believe the select button will toggle between AC and DC. 
 Hold the Zero button for a few seconds, you should see the screen zero out.

littleharbor2

Here's the manual.

https://www.manualslib.com/manual/461998/Uni-T-Ut203.html?page=3#manual

littleharbor2

I am getting the zero function confused between this and my Klein Tools clamp meter. After reviewing the manual , it seems there isn't a zero out function. 

mcgivor

Seems strange there is no zero button, both of mine have one, Ideal and UEI, but the readings differ anyway, the Ideal is my go to meter, it cost 5 times what the UEI did, the one touch zero makes it easier, but for what we're doing accuracies need to be ball park. In my opinion. 

BB.

The Delta Button is the zero button... With no current flowing/no wire in jaws, just push once and the meter should read 0.0

It is also intended for measuring differences in current flow. Put on wire with current flowing and push delta button for zero. Then if the current flow goes up or down, then the meter displays the difference (i.e., zero at 10 amps. Then if current goes to 11 amps, meter will show 1.0 amps or the Delta/Difference in current flow).

Note that DC meters do show +/- for direction of current flow (AC current meters do not).

-Bill

Estragon

Thanks guys, that helps. In playing around with it a bit, the zeroed meter reading seems to wander a bit, but should be close enough for most of my needs.

BB.

Yea, DC meters use a "Hall Effect" transistor to measure the magnetic field around the wire. They do drift some over time and temperature. For lower currents, you do need to re-zero the meter ever few minutes for accurate measurements.

-Bill