Recommendation for a reasonably accuarate DC Amp Clamp - Page 1
Forum section: electronics / testgear

author: Stray Electron
author_rank: Super Contributor
timestamp: May 24, 2024, 03:21:00 am
content: I just bought a car that contains alotof electronics and it shuts down various systems at different time delays after it's been turned off and I need be able to be able watch the current and be sure that each system is properly shutting down. And if they're not shutting down then I need to be able trace the current flow. So I'm looking for a clamp on DC Amp meter that can read up to at least 30 amps but that can also read down to about 50 Milliamps with reasonable accuracy.Does anyone have any recommendations?There is one discussion on the forum about a cheaphttps://www.eevblog.com/forum/beginners/hantek-cc-65-vs-regular-amp-clamp/msg5196507/#msg5196507Hantek Amp Clamp but it seems that it's not even close to accurate at low currents.

author: shabaz
author_rank: Frequent Contributor
timestamp: May 24, 2024, 04:28:02 am
content: I have aPico TA018, it's low-cost, and can resolve down to 10 mA (I hit the zeroize button occasionally, and then it does display at a scale of 1 mV per 10 mA, I've tested it down to 10 mA. That's in the 20A max range (there is also a 60A range with lower resolution).The TA018 comes with a BNC connector but easily adapted onto a multimeter.However it's Achille's heel is that it only supports up to about 9 mm diameter cables : (For a car, maybe it's possible to DIY a thinner wire temporarily onto the car battery for a short length, but I've no idea how feasible/unfeasible that is, or what issues that may cause since some cars might not like the supply being disconnected.

author: Stray Electron
author_rank: Super Contributor
timestamp: May 24, 2024, 07:37:14 pm
content: I wasn't aware of that model but I will take a look. Thanks.

author: thm_w
author_rank: Super Contributor
timestamp: May 24, 2024, 08:15:14 pm
content: Same recommendation for the past 5+ years has been UT210ehttps://lygte-info.dk/review/DMMUNI-TUT210E%20UK.html

author: DaneLaw
author_rank: Frequent Contributor
timestamp: May 24, 2024, 08:32:41 pm
content: Quote from: thm_w on May 24, 2024, 08:15:14 pmI reckon it's a unit intended for use with oscilloscopes when its CC65 and Pico's cheaper clamp-variant that are highlighted.Any tear down of the Pico TA018 ? is it a CC65 remolded rebadge' as the form-factor/circuit template looks very similar.OP, what's your budget, and are you locked on AC/DC clamps for scopes?I do personally have the CC65, and its accuracy is on call what I expected even down in the lower DC ranges, and works well with my Micsig scope' but you need to cycle the zero-button constantly, as its very sensitive and will drift.If its just to measure current on car-leads between 30mA and 30A and you don't need to test inrush' then I would pursue a tool like thm_w recommends above. fx UT210E or the tons of AC/DC alternatives with 1mA DC tolerances, and you can even get them with Bluetooth nowadays, which could be handy on a car' so you can place the clamp in hard-to-reach area, - and run certain things from the car while monitoring the values on an app.....Owon got a AC/DC clamp unit with BT/app.. have no experience with that model..Got the UT210E which performs quite well in lower mA values, it's more in the higher Amp-area I experience issues with my unit which tends to read a tad low (non-hacked) but in the lower span, it performs well...- some mA steptests are posted herehttps://tinyurl.com/3ykxb3ehbut you need to reset DC-value a lot if you want accuracy down the last mA, as it tends to drift, with that kind of hall sensor sensitivity

author: shabaz
author_rank: Frequent Contributor
timestamp: May 24, 2024, 10:05:21 pm
content: The Uni-T looks like the more appropriate tool. I have a Tenma (Uni-T re-badge) of a similar clamp meter, and forgot that may be more convenient for this situation.Quote from: DaneLaw on May 24, 2024, 08:32:41 pmI didn't want to take it apart too much since I use it, but from the internals it is for sure made by the same manufacturer as the Hantek one (Hantek photo on lygate website), maybe just a different model.The spring at the center is for the shielding (the plastic case is sprayed with a conductive coating).I think it's just a better constructed version perhaps (or a more recent revision). The three-pin device U5 is unfitted in the Hantek model, but there are pads there.

author: David Hess
author_rank: Super Contributor
timestamp: May 25, 2024, 12:12:58 am
content: I have been considering the B&K Model 316 which has 1 milliamp resolution on its 10 amp range.

author: Kean
author_rank: Unknown
timestamp: May 25, 2024, 01:38:12 pm
content: Check out the OWON CM2100. I've got a couple of these, as well as a few UT210E, a couple of unbranded ST-337's, and a few others. I quite like the Owons which are my newest purchase. They have 2A, 20A, and 100A ranges with 1mA resolution on 2A range (spec is 2%+/-8dig in 2A DC).There are two things annoying about the CM2100: (1) the buttons for AC/DC mode switch and Zero are a bit soft and respond poorly, and (2) if you mostly do DC current then you need to change mode and re-zero every time you power on or change range. I think having to re-zero with range change is the case on all the clamp meters I have, but some other models do at least default to DC.The ST-337 clamp meters looks slightly similar to the BK 316, but they are not identical. Not sure i want to pay the BK price.