Products > Test Equipment

A look at the Uni-T UT210E

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jayjr1105:

--- Quote from: AudioNoob on April 06, 2018, 09:15:03 pm ---yes, you need to set the upper limit to 9999. I've set my lower limit to 980.

--- End quote ---

Thanks, that did it.  I've updated my .ino file with final modifications.  I see roughly 10 people downloaded the previous one with the 10200 upper limit.  Hopefully they caught it and don't flash it.

maginnovision:

--- Quote from: rch on April 07, 2018, 09:48:38 am ---
--- 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.

--- End quote ---

Typically you can't do that for automotive stuff. By pulling power every module goes through a hard reset and if there is some issue where a module eventually stops going to sleep it'll then look like there is no issue. You really need to get a clamp that can read mA accurately without disturbing the vehicle.

rch:

--- Quote from: maginnovision on April 07, 2018, 03:42:52 pm ---
--- Quote from: rch on April 07, 2018, 09:48:38 am ---
--- 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.

--- End quote ---

Typically you can't do that for automotive stuff. By pulling power every module goes through a hard reset and if there is some issue where a module eventually stops going to sleep it'll then look like there is no issue. You really need to get a clamp that can read mA accurately without disturbing the vehicle.

--- End quote ---

How much precision is needed for automotive use?   At low currents it must be difficult to exclude the effect of the Earth's magnetic field.
Edit:  do much smaller jaws help at low current?

maginnovision:

--- Quote from: rch on April 07, 2018, 04:02:58 pm ---
--- Quote from: maginnovision on April 07, 2018, 03:42:52 pm ---
--- Quote from: rch on April 07, 2018, 09:48:38 am ---
--- 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.

--- End quote ---

Typically you can't do that for automotive stuff. By pulling power every module goes through a hard reset and if there is some issue where a module eventually stops going to sleep it'll then look like there is no issue. You really need to get a clamp that can read mA accurately without disturbing the vehicle.

--- End quote ---

How much precision is needed for automotive use?   At low currents it must be difficult to exclude the effect of the Earth's magnetic field.
Edit:  do much smaller jaws help at low current?

--- End quote ---

Depending on the vehicle/spec you need accurate mA readings. Small jaws could probably help but mostly because they're easier to use in small spaces. Stray magnetic fields are taken care of by zeroing near the battery before attaching clamp.

jayjr1105:
Okay Folks, I compiled a final version of the arduino code.  It's compatible with BOTH 0660 and 1106 chips!  As the code is, it will only work for the newer 1106 chip, you MUST uncomment and comment out certain lines for it to work with the older 0660 based models(notes in the code itself on how to do this).  Also remember to replace the calibration data from YOUR dump.  Otherwise you will have my calibration data.

You can copy/paste directly into IDE from here https://ghostbin.com/paste/6akt4

..or you can download the attached file. 

This file does just about every mod to the meter.  Simply comment/delete out what you don't want to use.

It would be good if someone could give it a once over for accuracy.

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