The BM235 does not accept lithium batteries

[MacMeter]

I haven't tried it, but if it works I can't think of any reason why not.

Thanks, I just want to avoid the inevitable leaking battery. After my bad past experiences I avoid alkaline batteries like the plague!

[mtdoc]

To get it to work with lithium batteries you just need to use a reverse batteriser.

[kcbrown]

I'm just glad Joe clued us in on the meter not working directly from the mains.  It was going to be the first thing I tried ...

 

[MacMeter]

To get it to work with lithium batteries you just need to use a reverse batteriser.

I caught up on most of the "batteriser" videos, what a nightmare, though highly entertaining and educational. There was one poster that in their opinion Dave might be a bit harsh, but considering not every potential buyer of those devices is not reading this forum, I think it's a great public service. If you are making outrageous claims for a product, you have to back them up, or face the music, and maybe get BUSTED! That's part of Daves appeal, I'm sure I would have bailed out on that stuff, far earlier, but to Daves credit, he pounds them for FALSE advertising and bogus claims, we need more of that for all products these days.

[texaspyro]

What I have done in such cases is to install a series schottky or even germanium diode in series with the lithium cells.   I used some very thin double sided copper foil strips (from old Aerotech "copperhead" rocket igniters).  Solder diode to each side of the copper strip and slip it between a battery terminal and the battery contact.  Tuck the diode in whatever nook or cranny you can find in the battery compartment.

The Copperhead igniters (aka crapperheads) used a conductive pyrogen.  One end of the strip was dipped into the pyrogen and the other end clipped to the launch controller using a clothes pin like thingy.  One major problem was when they sheared the strips off a larger sheet you often got short circuits along the shear.   I've also used the strips to insert things like current meters between various spring loaded connectors (like cell phone batteries).

[rstofer]

I haven't tried it, but if it works I can't think of any reason why not.

I wonder if the low battery voltage detection of 2.5V will get in the way.
Spec is in User Manual...

[IanB]

I wonder if the low battery voltage detection of 2.5V will get in the way.
Spec is in User Manual...

It doesn't seem to be an issue. I tested it with a pair of completely discharged* NiMH cells and even with the low battery indicator showing the meter still read accurately on voltage, resistance and diode test ranges, even with the back light on.

* I discharged the cells individually to the point that a 10 ohm load caused the cell voltage to drop below 0.35 V

[MacMeter]

That's an ideal "IanB", I could try running the new 1.8v Lithium AAA's down in a flashlight to maybe 1.6v to get to the under load limit of 3.0 volts. Or just go with the NiMH black Eneloops

[IanB]

Note that the low battery indicator doesn't show up if the cells are charged, so I think regular Eneloops will work fine. White Eneloops will be better than black Eneloops for low drain applications like this.

[MacMeter]

Note that the low battery indicator doesn't show up if the cells are charged, so I think regular Eneloops will work fine. White Eneloops will be better than black Eneloops for low drain applications like this.

Thanks, I have a bunch more of the white Eneloops, so I'll use those!

[Dan666]

Hi,
I'm new to the forum, but I've been following the eevblog YT channel lately, and that sparked an interest in electronics in me.
I used to have a cheap MultiMeter (actually I still have it) which I replaced with a Brymen 235 after discovering about it from eevblog itself.
As I'm trying to get rid of non-rechargeable batteries in my electronic devices, also because I fear leakage as someone suggested already, I'm using two Eneloop AAA batteries in my BM2335.
Today I was toying around with the EF functionality and from time to time the battery symbol appeared. It sounded strange to me that the batteries were already low, so I discharged them in the charger, and they still had ~630mAh (on a max of 750mAh).

I don't know if it's a quirk happening on the EF mode or what... my question, finally, is the following:

Is it OK to use rechargeable batteries with the Brymen 235 ?

cheers,
Danilo

[rstofer]

You should probably read through this thread where the battery issue is discussed at length.  The BM235 is very picky about battery chemistry (voltage).

The right answer, of course, is to read the manual and follow along.  In other words,

Batteries:
1.5V AAA Size battery x 2
240 hours continuous on Alkaline
NOTE: Lithium AAA's may need to be drained a small amount before use to drop the
initial terminal voltage.

Page 18 of the manual I downloaded from Dave's store:
http://www.eevblog.com/files/BM235-Manual-EEVblog.pdf

[Dan666]

You should probably read through this thread where the battery issue is discussed at length.  The BM235 is very picky about battery chemistry (voltage).

But I've read this thread, that's why I replied to it... You were talking about higher than expected voltage batteries, whereas a ni-mh is a bit lower but still within the range of voltage a non-rechargeable battery can provide.
Of course basically I don't know much about electronics, so if my questions seem stupid, it's because I still have much to learn...

The right answer, of course, is to read the manual and follow along.  In other words,

Batteries:
1.5V AAA Size battery x 2
240 hours continuous on Alkaline
NOTE: Lithium AAA's may need to be drained a small amount before use to drop the
initial terminal voltage.

Page 18 of the manual I downloaded from Dave's store:
http://www.eevblog.com/files/BM235-Manual-EEVblog.pdf

Yes, the non-eevblog (the one I have) one comes with the paper manual, which I've read thoroughly more than once, including the part about batteries, which BTW is a bit different, no words about lithium batteries or hours of usage.
It doesn't say anything about rechargeable batteries, but it says:

Low Battery: Below approx 2.5

which means that a ni-mh will be shown as low quite early.
I just wonder if the readings are still within specs in a low battery scenario...

[IanB]

I think Eneloops should work OK with the BM235, but I have not done extensive testing with my own meter. If you wait until this evening, I will have a chance to do a few experiments and report back.

[Dan666]

I think Eneloops should work OK with the BM235, but I have not done extensive testing with my own meter. If you wait until this evening, I will have a chance to do a few experiments and report back.

Well thanks!
In any case, the first thing I did after having received the meter was swap out the batteries for the eneloop, so I know it works with them, I just wonder if they fall short on duration and/or if its measurement are off when the batteries are low (which in case of the eneloop would be when the batteries are still quite full)

Nonetheless, this is a very nice meter, and if I compare it with the the other crappy one I have, it's light years ahead of it!

ciao,
Danilo

[MacMeter]

You should probably read through this thread where the battery issue is discussed at length.  The BM235 is very picky about battery chemistry (voltage).

But I've read this thread, that's why I replied to it... You were talking about higher than expected voltage batteries, whereas a ni-mh is a bit lower but still within the range of voltage a non-rechargeable battery can provide.
Of course basically I don't know much about electronics, so if my questions seem stupid, it's because I still have much to learn...

The right answer, of course, is to read the manual and follow along.  In other words,

Batteries:
1.5V AAA Size battery x 2
240 hours continuous on Alkaline
NOTE: Lithium AAA's may need to be drained a small amount before use to drop the
initial terminal voltage.

Page 18 of the manual I downloaded from Dave's store:
http://www.eevblog.com/files/BM235-Manual-EEVblog.pdf

Yes, the non-eevblog (the one I have) one comes with the paper manual, which I've read thoroughly more than once, including the part about batteries, which BTW is a bit different, no words about lithium batteries or hours of usage.
It doesn't say anything about rechargeable batteries, but it says:

Low Battery: Below approx 2.5

which means that a ni-mh will be shown as low quite early.
I just wonder if the readings are still within specs in a low battery scenario...

Bear in mind, Dave updates his online version of the manual, when he is alerted to any new info supplied to him, as well as what newer versions of the firmware may have fixed or changed. Unfortunately, you are stuck with whatever the firmware is that's currently on the meter when you buy it, as it's not user updatable. I have not switched to NiMH batteries yet, so I can't help there, and I may end up preferring to drain down some primary lithiums as an alternative. I do agree however with concerns over alkalines leaking, no matter the supposed expiration dates or brands, as it's hard to differentiate these days between clones and fakes. Every device in my house is either lithiums or NiMH, as I've experienced and lost devices that had bad leaking batteries. Shame the BM235 can't handle off the shelf AAA lithiums at 1.8 volts, but it's a fine meter.

[sequoia]

You should probably read through this thread where the battery issue is discussed at length.  The BM235 is very picky about battery chemistry (voltage).

The right answer, of course, is to read the manual and follow along.  In other words,

Batteries:
1.5V AAA Size battery x 2
240 hours continuous on Alkaline
NOTE: Lithium AAA's may need to be drained a small amount before use to drop the
initial terminal voltage.

Page 18 of the manual I downloaded from Dave's store:
http://www.eevblog.com/files/BM235-Manual-EEVblog.pdf

Just got low battery warning on my (EEVblog) BM235, so decided to try some Energizer Lithium cells on it.

I discharged each battery first for 10 mAh @ 100mA (360 seconds), then checked voltage after an hour or so and it was ~ 1.65V.

Not sure how Lithium batteries behave (?), have to see if battery voltage will creep up slowly enough to trigger the overvoltage after few days....

[MWisBest]

Just got low battery warning on my (EEVblog) BM235, so decided to try some Energizer Lithium cells on it.

I discharged each battery first for 10 mAh @ 100mA (360 seconds), then checked voltage after an hour or so and it was ~ 1.65V.

Not sure how Lithium batteries behave (?), have to see if battery voltage will creep up slowly enough to trigger the overvoltage after few days....

Once they're drained even slightly from a fresh pack they should be fine. I drained a pair at ~2mA for 5 minutes, they've sat at 1.7V for days since.