Modification of a Fluke multi meter that uses three AA batteries to use a 14500 lithium ion battery

[sam_sam_sam]

I have had with regular AA batteries that leak this meter is expensive new I already replaced the battery battery clips once and the same thing happened again and I am tried of so it is getting modified to accommodate lithium ion batteries that are the same size excluding the positive terminal and removing the battery clips I will have enough room for the BMS protection board

I going to put 3 lithium ion battery in parallel with the BMS protection board and a way to charge the battery externally and heat shrink the battery pack and use a JST connector so I easily remove the battery pack to make it easier to charge the battery pack

Or I might mount the JST connector to the battery cover so I do not need to remove the battery pack to charge it but I have not made up my mind yet on this part yet

The problem I have is that I do not use this meter very often but when I want to use it the meter does not want to power on so I have removed the battery cover and the battery clips are corrected and or have broken because of the corrosion

The reason I bought this meter in the first place was the fact that it has Bluetooth and the results from the meter can be seen on your phone or tablet and the software is decent for the part of the software that can be used for free it also put the results in a graphical display chart so you can see it over time if you want to have a document that can be printed or save in any other format then you have to pay for this option

Where I use to work I had a situation where a overhead crane was blowing fuses and destroying VFD drives that I needed a multi meters that I could see the voltages on all three phases on this crane after running this crane under heavy use I found out what the issue was it had a bad festoon cable that was under size for the crane's motor load and this cable had repaired several times which did not help the cause

I also have the clamp on current meters that has the Bluetooth function on it as well but if I remember correctly it has a 9 volt battery that does not have this issue

I will post pictures when I finish making the the battery pack

[sam_sam_sam]

Here is eBay link to the batteries that I am going to use for this project

https://www.ebay.com/itm/115018336665?epid=28012299999&hash=item1ac7a08999: g:E3IAAOSwVQZhVM-4&amdata=enc%3AAQAIAAAA4Hi%2BNh%2Fo0JPvZUvKIMlpH iC YRzoLEbfM17QsElbjGdXeW8ZVyt%2FEOApG9RWqEo83NGxPR20 ZzJrKLKSaLCOfjUk63r5BzHPsEt%2B7WAE1ZY2YnF%2BTY%2Fo 4NhvVUa2HCxeoIuAlqnpB795uNzMkVfBrGl3xoDRaOC9PC8b2t oPZkGjcT5ZtTIPcoRCZQtIymEz1otwQ1wZ56qSdIsMbWy0u9Rr YuFY1sfyYVZx8sZ3TF1b5pr4lsEyfEj2I9CcZwgBl7wXvwisrA p5wMCsBjvwUVi2UZhsi%2BF4ygSxOiwMYKlTk%7Ctkp%3ABk9S R4y0lv-XYw

One note the battery testing machine that the eBay seller is using is a decent battery testing machine I also have one and use it quite often SkyRc M3000 battery testing machine the graphics chart does not have very good detail because the chart is very small but it does give you an idea of what the status of the batteries under test are doing the application could have been done differently and better than it is

I would even be willing to pay for the application if the graphics chart was better for the voltage and current and temperature as it was a one time payment and not like Fluke does with there application that you have to pay each year for the graphics chart print option and some other features that it also has unfortunately it is not cheap and you can not choose what options that you want to use it only sold as a package

[sam_sam_sam]

Update

I finally finished testing the battery cells that I have for these two meters the amps hours are from 0.740 to 0.790 so I going to put 3 of them from the lower amp hour together and 3 from the higher amp hour together and I have one battery left that is 0.730 which I not going to use in this project

I have to buy some more of them from the eBay seller that has a lot of them for sale and only because they are only slightly used and almost new

One note the data sheet says the amp hours are 0.700 and I load tested at 0.100 amps which took a while to get to 2.8 volts

I just have to glue the batteries together and put the tabbing and the BMS protection board on it and wire it up and I should be back up and running again hopefully

[redwire]

What model is the Fluke multimeter?

[sam_sam_sam]

What model is the Fluke multimeter?

I will have to get this information tomorrow morning if I have time before I go to work in the morning

But it is the version that has the Bluetooth function on it and I have used it several times to troubleshoot intermittent power issues this is where this meter comes in very handy for this particular use

[redwire]

I was trying to understand what the plan is.
Old Fluke multimeter power is 3 of AA in series for 4.5V, and new plan is 3 of 14500 Li Ion 0.7Ah each in parallel for 3.7V?

[sam_sam_sam]

I was trying to understand what the plan is.
Old Fluke multimeter power is 3 of AA in series for 4.5V, and new plan is 3 of 14500 Li Ion 0.7Ah each in parallel for 3.7V?

I am aware that the battery icon will probably show that the battery is a little bit low I am not concerned about that when the battery pack goes low the BMS protection board will turn the power off or the meter will shut off either way this would be okay

I also thought about putting on two batteries in series and using a small buck converter in battery case but the issue with this is turning on and off the buck converter because if left on all time the batteries would be low each time I would need to use it

[прямо]

Why do you need more than one rechargeable Lithium battery?

I have modified my cheap meter to use just one 14500 3.7V 3300mAH that I salvaged from a laptop battery pack, instead of using 2x AA alkaline.

I solder two wires to the battery terminals and the end of the wires to a TP4056 module that cost only a cent. I stuck the module with 3M industrial double sided tape foam on the back side of the meter. When the battery is low, I connect the USB cable from a phone charger to the module and leave it until the battery is fully charged before using the meter again.

Absolutely no need to deal with BMS or even a buck converter module.

[sam_sam_sam]

Why do you need more than one rechargeable Lithium battery?

The reason for doing three 14500 is to have longer running time for data logging function that I use sometimes for troubleshooting intermittent issues with equipment
The reason for using a BMS protection device is for two reasons one being not to over charge or over discharge the batteries because if do not use a BMS device then your battery life will be unpredictable at a minimum or major malfunction of the battery cells plus the fact that I have a lot of BMS protection board for s one battery cell so it not like I have to go and buy any of them

I might consider using one of these TP4056 module but make it have a 500 milliamperes maximum charging rate but I would have to buy some of them because I only have battery pack versions and they are not very small in size

[redwire]

I think you might be better off going NiMH
Fluke 3000 FC "Three AA Alkaline batteries, Battery life: 250 hours minimum".
If Alkaline are around say 2,000mAh, and three of 14500 at 750mAh each is 2,250mAh total in parallel, and nothing to celebrate? Hi-cap Eneloop Pro are rated 2,500mAh.

... I have modified my cheap meter to use just one 14500 3.7V 3300mAH

Is this chinese specs? 3,300mAh is huge for such a small cell.


The danger is if the multimeter probes are connected to ANYTHING and you connect a battery charger.
There is a ground fault which will blow the multimeter chip. Power BAT(-) is not Input COM(-)! If it was connected/measuring mains then boom.
The TP4056 you can set charging current with one resistor but it's the connector hassle.

One IEC 61010 safety test is wrapping a multimeter in tinfoil, while giving high voltage at the test leads, as a shock test.
So the new battery pack must be HV insulated still, on the back. You don't want to be holding the meter and some connector touches your hand while you are making measurements on mains.

[прямо]

I guess I was half asleep when I typed 14500. I'm actually using 18650, so 3300mAH is correct. Not chinese specs. It's an authentic Sanyo battery. Very heavy too. A 14500 would be 1/3 of that at best.
Battery is placed in a holder and together with the module are taped on the back of the multimeter. I ran leads from the battery holder terminals to the multimeter board. The whole thing makes the meter a bit cumbersome but it works and battery lasts a lot longer than 2x AA.

I don't use it to measure high voltages. Mostly just for working on graphics cards. For power supplies I have another cheap Zoyi meter which I don't modify.

[sam_sam_sam]

I think you might be better off going NiMH
Fluke 3000 FC "Three AA Alkaline batteries, Battery life: 250 hours minimum".
If Alkaline are around say 2,000mAh, and three of 14500 at 750mAh each is 2,250mAh total in parallel, and nothing to celebrate? Hi-cap Eneloop Pro are rated 2,500mAh.


Is this chinese specs? 3,300mAh is huge for such a small cell.


The danger is if the multimeter probes are connected to ANYTHING and you connect a battery charger.
There is a ground fault which will blow the multimeter chip. Power BAT(-) is not Input COM(-)! If it was connected/measuring mains then boom.
The TP4056 you can set charging current with one resistor but it's the connector hassle.

One IEC 61010 safety test is wrapping a multimeter in tinfoil, while giving high voltage at the test leads, as a shock test.
So the new battery pack must be HV insulated still, on the back. You don't want to be holding the meter and some connector touches your hand while you are making measurements on mains.

I understand what you are saying about the using the meter with the battery terminals exposed out side of the meter but I can make the battery pack removable and charge it outside of the meter which is not a big deal to do it this way if this is safer to do

The issue with nicads is that the voltage is going to be a little low and might cause issues with the battery meter icon

1,25 X 3 = 3.75 versus 1.60 X 3 = 4.75 on the high end and the low end when the battery near the end of useful battery life
versus 4.20 on the high end and the useable voltage is usually around 3.0 volts

The other issue is that the replacement battery spring terminals are not worth a shit and I do not want to go through this hassle again each time I would have open the battery compartment and the battery terminal springs break again

Plus these battery spring terminals are not easily found and are not cheap for what they are

For the amount of money that you pay for this meter you would think that the battery spring terminals would be better quality than what they are REALLY

[Herbs n spices]

The multimeters I have all run on 9V batteries, and are dependent on the battery voltage to make accurate measurements. You should test if the lower voltage from the lithium cells (4.2-3.6v) affects your multimeter's accuracy as well.

Ni-MH batteries also have a lower nominal voltage than alkaline (1.2v vs 1.5v per cell), which is why I can't use a rechargeable Ni-MH 9v at only 7.2V nominal.

[redwire]

OT - 9V rechargeable batteries are available as NiMH 8.4V and others Li-ion that are 2S pouch inside or have a boost-converter/USB connector. For a multimeter I need something that doesn't drain dead so fast.
Varta P7/8 8.4V NiMH LSD looks good but I find Varta is a crappy brand, every one I've rarely encountered is a leaking dead thing.

For the 3000, do you let it store and then download the logs or is it always wireless transmitting data to a PC USB module? It looks really useful. I think the wireless uses the most energy.
It looks like li-ion has not much more energy over alkalines.
You can buy battery contacts on eBay.

[stj]

alkalines are shit,
the voltage curve as you discharge them drops fast.
lithium and NMH have a very stable curve and give good voltage till almost drained.

if i was going to put lithium inplace of some AA's i would try using a lithium pouch cell rather than butcher the case.

[petehall347]

look up tronic cells . lidl or aldi . long run time . only thing with them is no warning of needing charging .they work until they dont .

[прямо]

alkalines are shit,
the voltage curve as you discharge them drops fast.
lithium and NMH have a very stable curve and give good voltage till almost drained.

if i was going to put lithium inplace of some AA's i would try using a lithium pouch cell rather than butcher the case.

That's a very good idea. Unfortunately, most of the flat pack types being sold in the market are all jacked up Chinese specs. In reality, the capacity is lower than what's printed on the sleeve, yet people sells them at a price according to that print. So...

[redwire]

It's about filling the battery bay up as much as possible is what you want. Pouch batteries are not so thick and room would be wasted I think.
There must be something wrong with lithium 14500's to have lower capacity compared to other sizes? Maybe it's room needed for the BMS.

[sam_sam_sam]

There must be something wrong with lithium 14500's to have lower capacity compared to other sizes? Maybe it's room needed for the BMS.]

There is nothing wrong with these14500 they are low amperage type according to the data sheet I looked them up these are meant for low current devices Sanyo brand if I remember correctly it is extremely difficult to find brand name 14500 batteries I have checked off an for the last several years for brand name ones yes you can find the Chinese brand 14500 but there quality is shit and not worth the effort

I have a very good idea where this seller bought these batteries from I have a feeling that they were bought from Battery Hookup because about 6 months ago they had barrels of 14500 battery packs from a shaver company that were over stock and I tried to get Battery Hookup to sell me some but they were sold by a couple of barrels were sold in the auction part of there website my problem is that I do not need that many of this size I probably could use about 30 of at the most but battery Hookup has not had them listed for sale in the last 6 months or so