Do I really need a clamp meter when building a battery and installing a van electrical system? I have a Fluke 117 multimeter coming in the mail. Should I buy all the equipment I need to do a compacity test on new cells or just top balance them with the multimeter. The cells are new "Grade A" (thay say...) Jiangsu Frey cells from factory (assuming they are the manufacturer as they claim) bought on Jiangsu Frey Alibaba store. They have a company website but use Alibaba for sales. I'm tired of buying more and more equipment and tools. I'm already over what I estimated the cost to be lol.
Must I use a clamp meter
- Thread starter Jet
- Start date
As with any tool, it depends on what you wish to accomplish.
If you have a shunt then that can chart capacity.
A DC clamp meter is handy for troubleshooting, but isn't necessary.
I have a few of them. I got a $40 cheapo on Amazon or ebay, and I got a decent ideal meter from home depot around $90
If you have a shunt then that can chart capacity.
A DC clamp meter is handy for troubleshooting, but isn't necessary.
I have a few of them. I got a $40 cheapo on Amazon or ebay, and I got a decent ideal meter from home depot around $90
You don’t have to have one it just makes makes measuring current easy.
this so the one I bought for $25.00.
this so the one I bought for $25.00.
The Fluke 117 is a great little general purpose electrical multimeter, as long as you are aware of its limitations, mainly the limited resolution / precision that tends to only come into play in electronic work, vs electrical work which is the 117's strong point with built in proximity voltage detector, etc. I have one that I use as my grab and go multimeter these days, as it allows one hand operation, is a lot lighter and less bulky than my 87V. Now down to your question if you plan to read amps you need some method of doing it, either a clamp meter (note most clamp meters read AC amps only, better ones read AC and DC, or a shunt meter, etc. A cheap DC shunt meter that will read up to 500 A is only about $20 on amazon, or course a shunt meter must be wired in place which limits its ease of use..
A clamp on ammeter is not necessary to build a battery. As stated by by @Supervstech, the ammeter does come in handy when you're looking at what individual devices are drawing for current.
I might have used my ammeter when I did the top balancing, just to see if the number of amps in the cable were the same as what the power supply was reporting. That's illuminating when you compare the small wires the power supply comes with to a set of custom wires that are much larger. Otherwise, the battery build is all about volts.
I might have used my ammeter when I did the top balancing, just to see if the number of amps in the cable were the same as what the power supply was reporting. That's illuminating when you compare the small wires the power supply comes with to a set of custom wires that are much larger. Otherwise, the battery build is all about volts.
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pollenface
Solar Addict
Never used a clamp meter in my life but aim to get one at some stage. Just ordered my first shunt and power meter.
littleharbor2
Solar Addict
Keep in mind that there are AC and AC/DC clamp meters. If you need to monitor anything on the battery/solar side of things then you must have an AC/DC meter. Multi meters generally will test short circuit current up to 10 amps. This is not nearly as useful as a 400 amp, true current flow measurement.
Bluedog225
Texas
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FYI-That link says ”Do not measure DC current!” (All caps in original.)
Quattrohead
Solar Wizard
Yeah that one is no good, get this one for DC current and true RMS - https://www.amazon.com/dp/B07Z398YWF/ref=emc_b_5_t
I have this one - https://www.amazon.com/gp/product/B00O1Q2HOQ/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1
I have this one - https://www.amazon.com/gp/product/B00O1Q2HOQ/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1
You definitely don't NEED a clamp meter, but if you do any decent amount of DIY electrical work, you absolutely won't regret buying one. They save a lot of time.
You can also buy one, and resell it on eBay when you're done with your project.
You can also buy one, and resell it on eBay when you're done with your project.
I got in the clamp meter which I ordered, and plan to go down to the marina tomorrow and do some troubleshooting on the electrical issues on the boat.
My first time using a clamp meter and the question is how to use a clamp meter(I only learned about them the other day, when I posted about my electrical problem). So I looked on the internet to see how to use it to measure amperage. And thought that I understood it.
But some postings which I have read on here recently have me puzzled, so I thought someone might take pity and enlighten me.
It was my impression that in order to measure amperage, the meter has to be clamped around only one conductor. But if I understand the posting which I read yesterday, someone was measuring the amperage on the shore power cable by just clamping around the entire cable. I may have misread that, but don't think I did.
So I am puzzled, which is nothing new.
littleharbor2
Solar Addict
Your understanding is correct. You need to clamp only a SINGLE wire. Hopefully you ordered an AC/DC meter. Some descriptions are deceiving in that the meter reads AC and DC voltage but only AC current.
Hedges
I See Electromagnetic Fields!
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- Mar 28, 2020
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- 20,502
Clamping around multiple wires or the whole cable has its purposes.
If current flows out "Line" and back in "Neutral", or "Line1", "Line2", "Neutral", then meter clamped around whole cable should read zero.
But if meter is sensitive enough it may not. If some current is leaking out, e.g. getting into the water, there could be a few milliamps net current in the whole cable. Obviously that might be a safety hazard so what you saw might have been such a test.
Most clamp ammeters don't seem to read below 0.1A, and a few do 0.01A (I bought a Harbor Freight one which does.) That is useful for PV panels, distinguishing differences in DC current between parallel strings with a couple digits significant figures.
Big surprise for me, on the AC scale something carrying 0.1Arms read 0.00A on the AC range. Reads multiple amps OK. Cheap meter, I guess.
There are other meter meant for measuring AC residual current, spec 0.001A accuracy but have resolution to 0.000001A. Since human safety levels are around 0.005A, that is useful.
Lots of AC stuff has leakage to ground, due to capacitance. Especially electronics with EMI filters, which have physical capacitors from line to ground. We see a couple 1/10ths or whole milliamps from each of them. That current should still return in the ground wire (so meter around cable reads zero), but with water and earth as parallel path, some might take another route.
GFCI of course is supposed to detect this situation and trip.
If current flows out "Line" and back in "Neutral", or "Line1", "Line2", "Neutral", then meter clamped around whole cable should read zero.
But if meter is sensitive enough it may not. If some current is leaking out, e.g. getting into the water, there could be a few milliamps net current in the whole cable. Obviously that might be a safety hazard so what you saw might have been such a test.
Most clamp ammeters don't seem to read below 0.1A, and a few do 0.01A (I bought a Harbor Freight one which does.) That is useful for PV panels, distinguishing differences in DC current between parallel strings with a couple digits significant figures.
Big surprise for me, on the AC scale something carrying 0.1Arms read 0.00A on the AC range. Reads multiple amps OK. Cheap meter, I guess.
There are other meter meant for measuring AC residual current, spec 0.001A accuracy but have resolution to 0.000001A. Since human safety levels are around 0.005A, that is useful.
Lots of AC stuff has leakage to ground, due to capacitance. Especially electronics with EMI filters, which have physical capacitors from line to ground. We see a couple 1/10ths or whole milliamps from each of them. That current should still return in the ground wire (so meter around cable reads zero), but with water and earth as parallel path, some might take another route.
GFCI of course is supposed to detect this situation and trip.
The Fluke 117 is a fine investment in tools.
But to be honest, unless I'm doing board work, if I do need to measure current, I use a cheap little clamp-on dc ammeter. Close enough for hobby work.
Why? If you start switching betwen measuring voltage and current, and forget to move the leads on the multimeter, that Fluke fuse is kinda costly, and sometimes hard to find at times.
From a Fluke snob, this is very hard to admit in public.
But to be honest, unless I'm doing board work, if I do need to measure current, I use a cheap little clamp-on dc ammeter. Close enough for hobby work.
Why? If you start switching betwen measuring voltage and current, and forget to move the leads on the multimeter, that Fluke fuse is kinda costly, and sometimes hard to find at times.
From a Fluke snob, this is very hard to admit in public.
Hedges
I See Electromagnetic Fields!
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Yeah, at about $10 (to as high as $80??) apiece.
And I blow them even when I mean to measure current. Guess how much current a capacitor charged to 480V can deliver?
I'm a Fluke, HP, Tektronix snob. And I bought the HF Ames clamp meter (after looking at specs for Fluke and FLIR.)
www.harborfreight.com
For $100 it covered 10 mA DC resolution for PV strings to 1000A battery current and a few other things.
Also more portable than my 6 1/2 digit PPM stable bench meter.
diysolarforum.com
To see AC current with a scope, here's a picture of my Fluke i2000Flex. (I don't have a DC current probe yet.)
diysolarforum.com
And I blow them even when I mean to measure current. Guess how much current a capacitor charged to 480V can deliver?
I'm a Fluke, HP, Tektronix snob. And I bought the HF Ames clamp meter (after looking at specs for Fluke and FLIR.)
CM1000A 1000A T-RMS AC/DC Clamp Meter
Amazing deals on this 1000A T-Rms Ac/Dc Clamp Meter at Harbor Freight. Quality tools & low prices.
www.harborfreight.com
For $100 it covered 10 mA DC resolution for PV strings to 1000A battery current and a few other things.
Also more portable than my 6 1/2 digit PPM stable bench meter.
Accuracy of consumer grade DVM?
Hey Everyone, I am new to the Li battery arena. I am seeing the need to be measuring voltage and current with a level of accuracy that I have not needed in many years. I no longer have a bevy of Fluke and HP gear with recent cal stickers. I am looking at my current collection of gear and it is...
diysolarforum.com
To see AC current with a scope, here's a picture of my Fluke i2000Flex. (I don't have a DC current probe yet.)
High Frequency Inverter battery current waveform
In the interest of science ;) I have captured waveforms drawn by a high frequency inverter from the battery. This could give some insight to how a BMS might react. About 25 years ago I found myself with idle hands and some money ($800?) burning a hole in my pocket. I wandered into Quement...
diysolarforum.com
Heh, my own snobbery aside, my advice to new users is just to avoid the temptation to buy the lowest priced tools. One doesn't have to bust their budget just to get off the lowest rung.
Akin to buying a 400Ah battery, and using a 2A automotive wall-wart to charge it just to save some bucks.
Akin to buying a 400Ah battery, and using a 2A automotive wall-wart to charge it just to save some bucks.
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I have the same ammeter from a different "brand". It's a great value for your money, and I find myself using it more than my Fluke for the reasons stated above.CM1000A 1000A T-RMS AC/DC Clamp Meter
Amazing deals on this 1000A T-Rms Ac/Dc Clamp Meter at Harbor Freight. Quality tools & low prices.
