clamp meters

[Dak77]

I am an electronics noob , and I am looking for a clamp meter to read dc amps from battery leads and motors . Two that I've been looking at are the Fluke 324 plus and the Klein cl 800 . When looking at the specs, the Fluke's dc current range shows 40A/400A and Klein's shows 60A/600A . Does that mean it will not read 0-39 amps ?? I can't seem to find one that will read in the range that I need which is 0-60 amps or so . Am I totally misunderstanding the range thing?

 

[dustNbone]

It just indicates 2 ranges you can use. You'll get more precision on the lower range (an extra decimal place displayed).\

Probably .01A on the lower range and .1A on the higher one.

 

[flippy]

the "range thing" is a combination of the actual counts of the meter (this is important) and the range telss you the factor.
so a 6000 count meter on 60A has a resolution of 2 digits behind the decimal.

it can display 60.00A, at 600A it can only display 600.0A.
so feeding 6A to meter set to the 600A range gives you only 10 counts of range, so it displays 6.0A. but considering most DC meters are out by a 5~10 counts that means its just complely useless at those ranges but then again: if you need a 600A meter you dont care about 6 amps more or less.

if you keep below 60 amps just get a uni-t UT211B. its well accurate for measuring anyhting up to 60A.

 

[Dak77]

Thank you both . I definitely will never need a 600 amp or even 400amp range. I was having problems finding a meter that will do DC amps with an inductive pickup in my usage range . I just need an accurate volt meter ac and dc up to about 300v , inductive dc amp "clamp" that is accurate from 0- 200ish amps , and an audible continuity test . Just the typical things you would need from ebike measurements and in home general troubleshooting up to and including 220v AC .

 

[flippy]

please separate your current needs. try to use 2, one for low ranges up to 60ish amps and one for the big ranges beyond 100amps.
that way you get a smaller meter that is WAY more practical for measureing in tight spaces or one devices as the uni-t i mentioned is quite small and light. big 100+ amp clamps are huge and have big clamps that just are annoying when working on small stuff like bikes and scooters.

 

[flat tire]

Clamp ammeters are the wrong tool for your job. If you want to know current put in a shunt and log! Aka, get a watt meter.

 

[Dak77]

please separate your current needs. try to use 2, one for low ranges up to 60ish amps and one for the big ranges beyond 100amps.
that way you get a smaller meter that is WAY more practical for measureing in tight spaces or one devices as the uni-t i mentioned is quite small and light. big 100+ amp clamps are huge and have big clamps that just are annoying when working on small stuff like bikes and scooters.

Ok makes sense. Thanks for the advice. I would have probably ended up blowing a bunch of money on something I didn't really need.

 

[Dak77]

Clamp ammeters are the wrong tool for your job. If you want to know current put in a shunt and log! Aka, get a watt meter.

Are those cheap watt meters reasonably accurate? Like the $12 -$30 ones everyone seems to put their nameplate on , but they look exactly the same .

https://www.ebay.com/itm/Precision-rc-130A-watt-meter-and-power-analyzer-LCD-gt-power-60V-HTC/163803014133?hash=item26236ba3f5:g3UAAOSwHwNbjOIz

 

[dustNbone]

I have several of these and they are disturbingly accurate.

 

[Shunt]

I have several of these and they are disturbingly accurate.

That's good to know. I'll have to try one of these.

 

[flippy]

Those are off by about 5%.

The small clamp meter i pointed to is less then 1% and does not require you to cut into the wireing system.

 

[dustNbone]

Those are off by about 5%.

The small clamp meter i pointed to is less then 1% and does not require you to cut into the wireing system.

I've never seen one off by more than .02A, so I'm not sure where you get your 5% from.

 

[flippy]

I've never seen one off by more than .02A, so I'm not sure where you get your 5% from.

low current versions are probably better, but i only use the 100, 200 or 300A range and those shunts they supply are pretty shit.
accuracy of these things is mainly a case of winning the shunt-lottery.

 

[docw009]

I have several of the first type of wattmeter that was shown. Put in series, they will measure in the 1-30A range within 2-3% of each other. For voltage, they're too far off, reading as much as a volt apart, You also cannot leave them on a live battery as they do drain significant current over a period of several days.

I've used a Extech clamp-on ammeter at work. A good one is accurate, and useful when you cannot break into a circuit. An ebike nerd should have one.

 

[dustNbone]

I've never seen one off by more than .02A, so I'm not sure where you get your 5% from.

low current versions are probably better, but i only use the 100, 200 or 300A range and those shunts they supply are pretty shit.
accuracy of these things is mainly a case of winning the shunt-lottery.

Ahhh ok that makes sense. I've never used one of the included shunts, I get them from a local industrial electronics place and he calibrates them by hand.

I never considered using the included ones because they're physically huge.

 

[flippy]

Ahhh ok that makes sense. I've never used one of the included shunts, I get them from a local industrial electronics place and he calibrates them by hand.
I never considered using the included ones because they're physically huge.

yup, that's the ticket. i got some pretty expensive shunts in my "good stuff" drawer and those are made forged by virgin elves under blue moonlight (and cost a pretty penny) and then its fine. but i am not using shunts in a scooter that cost about as much as the whole scooter.

its all about using the right tool for the job and use the accuracy when you need it. that is why i dont like using high range current clamps for low power applications like basic bikes and scooters. that cheap uni-t i mentioned is perfect for the kids stuff we generally talk about here.

 

[Dak77]

Ahhh ok that makes sense. I've never used one of the included shunts, I get them from a local industrial electronics place and he calibrates them by hand.
I never considered using the included ones because they're physically huge.

yup, that's the ticket. i got some pretty expensive shunts in my "good stuff" drawer and those are made forged by virgin elves under blue moonlight (and cost a pretty penny) and then its fine. but i am not using shunts in a scooter that cost about as much as the whole scooter.

its all about using the right tool for the job and use the accuracy when you need it. that is why i dont like using high range current clamps for low power applications like basic bikes and scooters. that cheap uni-t i mentioned is perfect for the kids stuff we generally talk about here.

I ordered that Uni-t unit , but I want to put some good leads on it. Are they the same type that fluke uses ? They look like it, but I wanted to make sure they weren't female plugs .

 

[flippy]

I ordered that Uni-t unit , but I want to put some good leads on it. Are they the same type that fluke uses ? They look like it, but I wanted to make sure they weren't female plugs .

the leads are regular pvc, so a bit stiff.