Products > Test Equipment
A look at the Uni-T UT210E
AudioNoob:
I've had a bit of confusion while measuring small DC currents with the clamp today. My car is sucking more current from the battery than it should in standby, and I was probing a couple different wires connected to the battery to find the culprit. My method, which seemed to had worked just fine before, is to touch the wire with the tip of the closed clamp, zero the meter a couple times until the display stays at zero for at least a couple seconds, and then open the clamp, move it onto the wire and close the clamp.
So it worked fine, until one wire showed something around 15 mA. Except I know it's not passing any current because just 10 cm down the same wire there's a fuse that I pulled out. Bottom line: I had to repeat the measurement a couple times holding UT210 at various angles until it finally displayed zero.
Now, I know the clamp is not that accurate with extremely low currents like 0-100 mA, but it's been astonishingly accurate for me thus far (for a clamp) and I haven't had such a problem before.
Am I doing the measurements wrong? What can I do to avoid such issues and get readings as reliable as possible?
jayjr1105:
--- Quote from: Kbird on April 06, 2018, 02:28:17 am ---Hi , great !.... glad I could help a bit with your Mod , my guess is you know know more than I do :)
especially about the 1106 Chip.....
--- End quote ---
Found a little bug with STJ's 10,000 counts setup on page 17...
--- Quote ---make 10,000 count <<< only DM1106 chip, will fuck AC readings on DTM0660 chip
10 = 10 (normally 70) default count:6000??? 2000>10000
11 = 27 (normally 17)
12 = d8 (normally 98) upper switch point 2200>10200
13 = 27 (normally 08)
14 = d4 (normally be) lower switch point 190>980
15 = 03 (normally 00)
--- End quote ---
Whenever I use my 10v precision voltage source, it goes OL. 9.999 is fine but as soon as it hits 10.00 it goes OL and doesn't range up. I'm thinking it has something to do with this
--- Code: ---12 = d8 (normally 98) upper switch point 2200>10200
13 = 27 (normally 08)
--- End code ---
AudioNoob:
yes, you need to set the upper limit to 9999. I've set my lower limit to 980.
maginnovision:
--- Quote from: AudioNoob on April 06, 2018, 08:25:52 am ---I've had a bit of confusion while measuring small DC currents with the clamp today. My car is sucking more current from the battery than it should in standby, and I was probing a couple different wires connected to the battery to find the culprit. My method, which seemed to had worked just fine before, is to touch the wire with the tip of the closed clamp, zero the meter a couple times until the display stays at zero for at least a couple seconds, and then open the clamp, move it onto the wire and close the clamp.
So it worked fine, until one wire showed something around 15 mA. Except I know it's not passing any current because just 10 cm down the same wire there's a fuse that I pulled out. Bottom line: I had to repeat the measurement a couple times holding UT210 at various angles until it finally displayed zero.
Now, I know the clamp is not that accurate with extremely low currents like 0-100 mA, but it's been astonishingly accurate for me thus far (for a clamp) and I haven't had such a problem before.
Am I doing the measurements wrong? What can I do to avoid such issues and get readings as reliable as possible?
--- End quote ---
Buy a proper low amp current clamp. Generally a 10/20A clamp is good enough to measure sleep currents. I've never used a meter like these for that job. I have an amprobe that was just as accurate as the $8k clamp we used at work, however the amprobe is just a clamp and didn't log anything.
rch:
--- Quote from: AudioNoob on April 06, 2018, 08:25:52 am ---I've had a bit of confusion while measuring small DC currents with the clamp today. My car is sucking more current from the battery than it should in standby, and I was probing a couple different wires connected to the battery to find the culprit. My method, which seemed to had worked just fine before, is to touch the wire with the tip of the closed clamp, zero the meter a couple times until the display stays at zero for at least a couple seconds, and then open the clamp, move it onto the wire and close the clamp.
So it worked fine, until one wire showed something around 15 mA. Except I know it's not passing any current because just 10 cm down the same wire there's a fuse that I pulled out. Bottom line: I had to repeat the measurement a couple times holding UT210 at various angles until it finally displayed zero.
Now, I know the clamp is not that accurate with extremely low currents like 0-100 mA, but it's been astonishingly accurate for me thus far (for a clamp) and I haven't had such a problem before.
Am I doing the measurements wrong? What can I do to avoid such issues and get readings as reliable as possible?
--- End quote ---
The most accurate way is to turn the current in the device being tested off and zero the clamp with the wire inside it, and make the measurement without allowing the clamp to change position or orientation at all but by turning the device on. This is probably not appropriate for your use, as disconnecting the battery would upset the baseline measurement conditions even if it didn't cause more major problems for the vehicle. I suppose the spurious 15mA is a not unreasonable sort of error from moving the clamp around very slightly after zeroing.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version