I just got my UT33A DMM and noticed that the test leads that came with it can only measure current up to around 2A. I have a flashlight that draws ~3A and the DMM with standard leads showed just under 2.1A. I tried with thicker copper wires and it showed ~3.1A.
Anyone else noticed that the standard test leads that comes with the UNI-T UT33A have trouble measuring above 2A?
Could someone recommend some new (and cheap ) test leads for this DMM that can measure at least up to 4A?
The leads are 105 cm (including the probe). I forgot that the battery I used when taking the initial readings wasn't fully charged so that explains the ~2.1A readings with the original test leads.
I found some new test leads at the local electronics shop that are rated 10A, 1000V. The following text is printed on the side of the new test leads: AWM 1803 E199279 VW-1 80°C 18AWG 2000V Leo Hui (UT33A original leads didn't have any text on them).
I tested a flashlight with a 18650 @ 4.11V:
UT33A original leads: ~2.75A
new leads: ~3.30A
I also tested the Trustfire C8 XM-L T6 from Manafont with a 18650 (Sanyo) @ 4.10V and the tailcap reading was 2.84A with the new leads (UT33A original leads showed a tailcap reading of 2.23A with the same battery).
So I guess the 18 AWG test leads are better/more accurate?
In general with test leads, the heavier the better (As long as they'll still bend) and the shorter the better. These DX ones aren't bad at all and aren't horribly overpriced like the ones I can buy locally.
What I actually use for larger current measurements is some 2.5mm2 solid copper wire left over from rewiring the house. About 14AWG.
I have some 6mm2 stuff but it is just too awkward to use (According to Google around 10AWG). It has a mind of its own when it comes to bending to make contact. The 2.5mm2 stuff is awkward enough.
The DX ones aren't as good as they used to be, according to the comments (edit: just noticed that what I was looking at was from our very own brted). The pair that came with my VC99 look identical and I measure almost half an ohm (500 mohm) of resistance when touching the leads together. In comparison, when I use the leads from my hobby charger with ~14ga wire and gatorclips I get a reading of 0.0 or 0.1 ohm. (I haven't made a setup for milliohm testing yet, so those numbers are really on the edge of being irrelevant)
I have these but they aren't quite as free-flowing as my hobby charger leads, but they work fine for most instances.
) test leads for this DMM that can measure at least up to 4A?