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Recommend me a multimeter ?

ianganderton

Auckland, NZ
Joined
Nov 8, 2019
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Auckland, New Zealand
Sorry I know this question gets asked a lot and I’ve read quite a bit about it but can’t decide

I’m after a multimeter for use building my camper van. DC 12V. AC 240V 50hz. 200A plus DC (2000-3000W inverter). 200Ah Lifepo4, 400W solar

Is it possible to record data to understand power use and surges etc? Eg tracking the power use of a diesel heater or a fridge

Clamp meter? Probes? Temperature?

I also play a bit with arduino type projects.

Thanks

Ian
 
Depends on budget naturally, but a Fluke 233 with the removable remote head is very handy for doing things like making remote adjustments at the back of the camper, while the probes are on something in the front - and you don't have a helper.

The Fluke 289 logging multimeter can be pretty handy too for an all-in one with graphing and so forth, catching quick transient dropouts, stuff like that, but I'm still saving up for one. :)
 
As an EE I really liked the HP 6 digit DVMs they had at work, but my favorite go to meter at home is a cheapo Crenova I picked up on Amazon. For temperature I use a solid state probe that puts out 1 uA/°K so it is easy to connect it to a 12V source and read uA to know just what the temperature is. I admit I do need a clamp on ammeter.
Or here is an Arduino LM35 temperature solution which might interest you: https://www.engineersgarage.com/arduino/measuring-room-temperature-with-lm35-using-arduino/ You can pot the LM35 inside a small tube and attach a cable for remote sensing.
 
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Choose what fits your needs. But it's also a matter of who-ya-gonna-trust-FIRST?

Ie, a reference you use to verify or spot check other things. Ie, I'd be more than satisfied to use @pollenface 18b+ to make sure that out of the box, that multifunction battery monitor was actually following it's own spec and reassure me that I didn't get a lemon that was 0.2v out!

With LFP sometimes a tenth of a volt or two can make a big difference depending on a charge / discharge strategy.

It's that whole First-trust level. A Fluke 11x range more than satisfies that need to be the reference for everything else I purchase to be the final arbiter right?

But to each his own.
 
Choose what fits your needs. But it's also a matter of who-ya-gonna-trust-FIRST?

Ie, a reference you use to verify or spot check other things. Ie, I'd be more than satisfied to use @pollenface 18b+ to make sure that out of the box, that multifunction battery monitor was actually following it's own spec and reassure me that I didn't get a lemon that was 0.2v out!

With LFP sometimes a tenth of a volt or two can make a big difference depending on a charge / discharge strategy.

It's that whole First-trust level. A Fluke 11x range more than satisfies that need to be the reference for everything else I purchase to be the final arbiter right?

But to each his own.
Agree. You need to purchase a meter with a good accuracy. This is also for your safety. I have Fluke 117 multimeter (w/calibration certification). For current measurement, you can use shunt Wattmeter for about $20 (20A max rating).
 
The Fluke 117 is fine for our needs as the system reference for most voltage measurements. Anything in the 11x series makes a great bottom-end. The lower 10x series, I don't use for lithium based systems.

I may seem like a Fluke-snob, but not so. Unlike potato-chips, you only need one. :)

And it doesn't even need to be calibrated-certified. Out of the box, I sleep well enough. It's not my only meter to be sure, but it resolves any system-level disputes, and in some cases proof enough that other things need to be fixed or returned.

A vendor requesting a picture-shot showing your Fluke on a device usually gets no question. The Volt-O-Matic 2000, then eyebrows raised. :)
 
So I’m trawling through options.

Wills recommendation on his site of for the Klein MM400 multi meter and CL380 clampmeter

the Fluke 117 and 325 seem to be the equivalent. The 325 looks like it measures 400A of DC current.

uni-T 71D multimeter gets good functionality reviews (inc data logging) at a good price

The pair of Kleins option is easy
 
Oh, if you want multimeter teardown p0rn, be sure to see Dave's EEVblog whole series. Here's one of the latest:


His enthusiasm about the subject is just infectious. :) You can't stop watching.

No sweat - there is a lot of good stuff. I just like having at least one Fluke around, since nobody questions it if say a vendor wants to see a pic before getting an rma, things like that.
 
I went witht he tacklife cm06. it's supposed to be just as good as the flukes

 
I went witht he tacklife cm06. it's supposed to be just as good as the flukes

I have one, it is off by two millivolts compared to my Fluke. Guess which one is the one I trust.

But the tacklife is a decent meter for the price.
 
So I’m trawling through options.

Wills recommendation on his site of for the Klein MM400 multi meter and CL380 clampmeter

the Fluke 117 and 325 seem to be the equivalent. The 325 looks like it measures 400A of DC current.

uni-T 71D multimeter gets good functionality reviews (inc data logging) at a good price

The pair of Kleins option is easy
For the clamp meter, I ordered this

I also have the CL380, but it lacks the peak tracking to get surge.
I can recommend the Klein 10x loop and A/C separator device.
 
I recommend Fluke 376 FC, clamp meter. It has capability for AC/DC, bluetooth to connect to your cellphone or mobile device for bigger screen and has logging history as well.
So far, I'm very happy with it.
 
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I recommend Fluke 376 FC, clamp meter. It has capability for AC/DC, bluetooth to connect to your cellphone or mobile device for bigger screen and has logging history as well.
So far, I'm very happy with it.
That's actually quite reasonable for a Fluke with data logging capabilities.
 
I think I’m narrowing down to the Uni-t UT61 series. It seems to fall into the good enough sector but with datalogging via USB connection to pc

the choice looks to be between the UT61D+ (NZ$70) and UT61E+ (NZ$105)


I don’t fully understand the difference so will likely go for the cheaper option

It makes sense to get one of the uni-t clamp meters at the same time. Unfortunately it doesn’t seem there is one available with a datalogging option so I’ll ask for opinions on which one I should get to complement the UT61 multimeter.

clamp meter requirements
400A DC or more
Auto ranging
Temperature

the clamp meter would likely live in the van
 
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I think I’m narrowing down to the Uni-t UT61 series. It seems to fall into the good enough sector but with datalogging via USB connection to pc

the choice looks to be between the UT61D+ (NZ$70) and UT61E+ (NZ$105)


I don’t fully understand the difference so will likely go for the cheaper option

It makes sense to get one of the uni-t clamp meters at the same time. Unfortunately it doesn’t seem there is one available with a datalogging option so I’ll ask for opinions on which one I should get to complement the UT61 multimeter.

clamp meter requirements
400A DC or more
Auto ranging
Temperature

the clamp meter would likely live in the van
Looks like the big difference is accuracy and significant digits.
For LiFePO4 you probably want more than 3 significant digits, i.e. you probably want the expensive one with 5 significant digits for DC volts.

If you don't need the surge ability, the Klein 380 is decent for a clamp meter.
 
I recommend Fluke 376 FC, clamp meter. It has capability for AC/DC, bluetooth to connect to your cellphone or mobile device for bigger screen and has logging history as well.
So far, I'm very happy with it.
@NOLA_Castle , I have the Fluke 376 FC as well... I'd like to use this for measuring LiFePO battery voltages. The problem is that I can't figure out how to increase it's resolution. For example, if I measure the battery, I just get 3.2 v. I want to get it to atleast show the hundredths like 3.29 v.
 
If you are really wanting to set bench power supply voltages or calibrate a BMS, you really need a good multimeter that is both accurate and precise. Those are different things. Lots of the cheapo meters are neither. I have a couple of the cheap ones, and they are good for many things. One of mine is a Harbor Freight meter with a AC/DC clamp meter. For measuring current with a clamp meter, a cheaper meter is usually fine.

There have been lots of Fluke meters recommended, and that's for good reason. Mine is a Fluke 175, and I think it cost me something like $250 maybe 4 years ago. I'm happy with it, but you would probably be fine with cheaper models.
 
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