Measuring amperage in vehicle?

[SuzukiGS750EZ]

Hey guys. I'm looking for an amp clamp to measure starter current, alternator current and current to my amplifiers. Would be nice to measure lower current for say blower motor and even smaller circuits. I have and regularly use a multi meter. Suggestions?

 

[General Geoff]

amp clamps are not particularly accurate for DC. Best way to measure is with a current shunt in-line

 

[jsaw]

I have a cheap one. I paid $35 from Amazon. compared it with a more expensive meter, and it was accurate.

 

[tool_scrounge]

The Extech MA445 clamp on meter is pretty nice for about $71 from Amazon.com

It will handle up to 400A DC and has resolution down to 10mA DC I presume in the lower current ranges.

http://www.extech.com/products/MA445

 

[Wrench97]

Fluke 325 does DC current.

 

[Mr_B]

buy amp clamps that you can use with existing dmm .
also look at uni-t 204A for high current and uni-t 210E for low current, around 35 to 45 bucks via eBay and maybe cheaper if hunt around .

 

[SuzukiGS750EZ]

buy amp clamps that you can use with existing dmm .
also look at uni-t 204A for high current and uni-t 210E for low current, around 35 to 45 bucks via eBay and maybe cheaper if hunt around .

I would like the plug in type as I also have o-scopes. I just don't know what's worth while to purchase for both high and low measurements.

 

[dscheidt]

I have a cheap one. I paid $35 from Amazon. compared it with a more expensive meter, and it was accurate.

I bought a similar one. I'm surprisingly happy with it. It's got both 60A and 600A scales. It's accurate enough, if you can zero it out in place. the hall effect sensors that DC meters use is sensitive to interference, so they will all pick up stray magnetic fields, and have an erroneous reading. I've used it to diagnose alternators, starters, track down some parasitic draws. I also use it as a second DMM, but it's auto-ranging, and I hate auto-ranging meters.

Remote reading clamps have a big advantage if you need to get them on a hard to reach wire (or put them on a starter, and turn the key from the seat, and see the results.), but a small self contained unit is handier to carry around.

 

[richfinn]

I would like the plug in type as I also have o-scopes. I just don't know what's worth while to purchase for both high and low measurements.

You need both a high (600a) and low (60a) current clamp, I have the Tecpel which pico used to supply

They sell both 4mm banana plug or BNC connection types

I have seen people using the Hantek clamps successfully too

 

[Aeromech]

I like this one

Uni-T B4Q094 UT210E True RMS... https://www.amazon.com/dp/B00O1Q2HOQ/?tag=atomicindus08-20

 

[2ndGearRubber]

amp clamps are not particularly accurate for DC. Best way to measure is with a current shunt in-line

How's that? My 20/60 clamp was good enough to fix a p0420 cat-converter efficiency code by finding two bad injectors. My clamps fix quite a few issue, from shorts in windings to bad electric motors, hell even bad internal combustion engines with mechanical faults.

I will agree, for super long time bases, or parasitic draw, voltage drop across a resistor has advantages.

You need both a high (600a) and low (60a) current clamp, I have the Tecpel which pico used to supply

They sell both 4mm banana plug or BNC connection types

I have seen people using the Hantek clamps successfully too

This right here. The ideal setup IMO is a 20/60amp setup with small jaws, and a larger jaw high current probe for battery cable applications. How wild you want to get with the high current probe, is a matter of budget. I love my 200/2000amp probe from Pico, but a 600 amp probe works very well for most users doing basic testing of high current circuit testing. A generic 600amp probe was my first high current probe, and worked very well.

High current is for relative compression (can also use voltage), and charging systems primarily. Low current probes are for everything else - fuel pumps to injectors to blower motors to a/c compressors to air suspension to ignition coils and radiator fans.

 

[bwringer]

Yep, a DC amp clamp is the handiest thing on the planet for diagnosing vehicle electrics. It's almost weird how hard they are to find.

They can actually be pretty accurate, but there are very few situations where 1/10 or 1/100th amp accuracy would make the slightest difference.

If you really are measuring milliamps, then use a multimeter inline as is tradition.

Mine is a Craftsman brand I bought several years back. Not sure who actually made it.

 

[javyLSU]

I’ve got that Uni-T 210E, and it’s my most frequently used DMM for automotive work. For measuring higher than 100A, I have a Snap-on auto ranging meter - but that Uni-T is awesome for most of what I need, especially currents of 6A or less. It’s small, and does well to clamp around wires jammed in tight spaces and shoved into harnesses.

 

[SuzukiGS750EZ]

Would these two be good, or are there better in the price range/amps reading?

http://www.esitest.com/697.html

http://www.esitest.com/695.html

 

[SuzukiGS750EZ]

I think I've dwindled it down to:

https://www.aeswave.com/High-Amp-Probe-with-Banana-Plugs-p9673.html

https://www.aeswave.com/Low-Current-Probe-0-80-Amps-p8987.html

Or

http://esitest.com/697.html

http://esitest.com/695.html

 

[Wrench97]

I do have the AESwave high and low amp clamps for my scope, they work well.
I use the Fluke more often for quick checks as it's just faster to use.

 

[2ndGearRubber]

I have that 600amp probe, works well. Look on the aeswave site for the pico 20/60 clamp, theres usually lots of people rebranding that for less money. Pdi and aeswave used to have their own. Covid related supply shortages maybe?

My esi meter is of good quality. Cant say anything about their probes.

 

[anndel]

I like this one

Uni-T B4Q094 UT210E True RMS... https://www.amazon.com/dp/B00O1Q2HOQ/?tag=atomicindus08-20

I have this counting on 5 years now and it helped troubleshoot current drains on several vehicles. 100A DC Amps helps with starter and alternator issues.

 

[SuzukiGS750EZ]

I bought the two AES wave clamps. I've got to figure out wastage of my current amplifier, what the alternator is putting out at full tilt and what the amplifier is getting at the back of the car.

 

[xjfish]

I do not own a decent low amperage amp clamp. After this and another old thread, Uni-T UT210E is ordered. Thanks! For under $50 should be an awesome tool.

 

[SuzukiGS750EZ]

I do not own a decent low amperage amp clamp. After this and another old thread, Uni-T UT210E is ordered. Thanks! For under $50 should be an awesome tool.

You're welcome! I've already thought of multiple uses I'll have for them outside of car audio.

 

[Mr_B]

I do not own a decent low amperage amp clamp. After this and another old thread, Uni-T UT210E is ordered. Thanks! For under $50 should be an awesome tool.

They fairly decent for some basic auto testing .
speed and stability of clamp main thing stop it being amazing along with default eeprom being less than ideal in default AC start setting and backlight/auto off timeout .
Much better if change some of the eeprom values for menu order, backlight timeout etc ...
eeprom programmer and chip clip was less than 10bucks few years back when I done it, the meters were around 30bucks back then .
I have a couple in shop as was so cheap for useful quick tool but a 100buck quality clamp is different league ...

 

[javyLSU]

They fairly decent for some basic auto testing .
speed and stability of clamp main thing stop it being amazing along with default eeprom being less than ideal in default AC start setting and backlight/auto off timeout .
Much better if change some of the eeprom values for menu order, backlight timeout etc ...
eeprom programmer and chip clip was less than 10bucks few years back when I done it, the meters were around 30bucks back then .
I have a couple in shop as was so cheap for useful quick tool but a 100buck quality clamp is different league ...

I reprogrammed mine as well, and it's PERFECT now for what I use it for.