What do you prefer powering your multimeters (or other equipment)? - Page 1
Forum section: electronics / testgear

author: XOIIO
author_rank: Super Contributor
timestamp: May 01, 2014, 08:43:26 am
content: Simple question, and something that steered me towards getting a different multimeter, the mastercraft one I owned before got a design update, and changed over to two AA or AAA batteries to power it, and that was something I wanted to avoid, I just feel like the 9v is a vastly superior option, especially since most multimeters are able to drain it down pretty low whereas with AA or AAA's, they give a low battery at 2 volts or even a bit higher,

author: BravoV
author_rank: Super Contributor
timestamp: May 01, 2014, 09:37:49 am
content: Don't think you can choose what cell size/type the meter use easily. For me, the best still AA sized since I can use the low discharge NiMH cell, while the 9V NiMH are really wimpy.Regarding cell types, for 9V based, I use exclusively only Panasonic alkaline cells that are made in Japan, nothing else. I've been using it for > 20 years and no leakage.While for AA or AAA cells, only rechargeable Eneloop cells are allowed to touch my multimeters.A nasty example of the damages that my 287 experienced, it was a display unit when I bought it, came installed with "fresh" alkaline cells (measured) that still have long expiry date, fyi the shitty alkaline cells photo was shot last year.

author: mariush
author_rank: Super Contributor
timestamp: May 01, 2014, 10:12:45 am
content: Some meters need that higher voltage that a 9v battery provides... some use a 5v linear regulator, some do a +/- 3-5v from the 9v battery.There are some exceptions (like the UT61E meter) which works with even less than 3v but is powered from a 9v battery because they reuse the case and the case has a 9v compartment.9v batteries generally have only 150-170mAh. AA batteries can go up to about 2850 mAh. Alkaline batteries are generally 1800-2200mAh (but have higher voltage than rechargeables so they last as much or eve more)So in theory, multimeters running from AA batteries should have a longer battery life.With my UT61E, i've designed a small "battery", basically a board with a LT1307 and a 20F 2.7v supercapacitor that fits in the 9v battery footprint and a separate small charger (usb 5v -> 2.65v). The "battery" charges in 5 minutes and keeps the meter running for 1h+... lt1307 boosts 1v-2.7v from supercap to about 5.7v (minimum before ut61e says low battery, even though it runs perfectly fine with as low as 3v). With less than a minute of charge, the meter runs for 20-30 minutes. If I make it boost to 3-3.5v, it would probably last 3-4h on a charge.

author: poorchava
author_rank: Super Contributor
timestamp: May 01, 2014, 10:14:59 am
content: I prefer AA batteries just because they are the cheapest and the most available.As for my own creations I prefer lithium-ion cells with one chip charger (generally MCP73832).

author: han
author_rank: Frequent Contributor
timestamp: May 01, 2014, 10:17:43 am
content: Rechargeable AA Battery,More juice than 9V one..

author: Zbig
author_rank: Frequent Contributor
timestamp: May 01, 2014, 10:59:54 am
content: For me it's option 5:It's not a factor for me at all when choosing a multimeter. I would consider it silly to make your buying decision based on one primary cell (/battery) form factor or another rather than, you know, actually important features and parameters. If anything, I'd tend to lean towards internally rechargeable Li-Po if that's an option but I'd definitely lump all types of alkalines together.

author: Christe4nM
author_rank: Unknown
timestamp: May 01, 2014, 11:04:42 am
content: Option 5 seconded.But suppose if battery choices were possible:If it were to be between 2x AA, 2x AAA and 9v I would go for the single 9v block. But I chose "other" since I actually prefer 4x AA. 4x AAA coming second. Eneloop rechargeables off courseSo I actually miss the options for 4x AA and 4x AAA those are common IIRC.

author: XOIIO
author_rank: Super Contributor
timestamp: May 01, 2014, 11:23:18 am
content: Quote from: Christe4nM on May 01, 2014, 11:04:42 amHmm, I've never seen a multimeter that uses four AA or AAA batteries.

author: SeanB
author_rank: Super Contributor
timestamp: May 01, 2014, 11:58:38 am
content: Looking at the leak samples made me go look at the batteries in all my test equipment quickly. No leaking cells there, and no expired ones either.

author: Excavatoree
author_rank: Frequent Contributor
timestamp: May 01, 2014, 12:21:02 pm
content: I see many complaints from people about why meter X uses battery type Y, but frankly, it's never been a concern of mine.I have had problems with the AA contacts in my 87-IV, 89, 187, and 189 meters. (I forget which two or three out of the four I have) It seems the higher voltage meters do better with resistance readings.

author: vk6zgo
author_rank: Super Contributor
timestamp: May 01, 2014, 12:27:43 pm
content: My old Fluke 77 goes for ages on a 9 volt alkaline battery,so I'm happy with them.

author: BravoV
author_rank: Super Contributor
timestamp: May 01, 2014, 12:39:57 pm
content: Quote from: SeanB on May 01, 2014, 11:58:38 amJust remember to check them periodically.Those my leaky examples even with expired date on March 2017, were thoroughly tested (with load) and they're still very fresh.

author: SeanB
author_rank: Super Contributor
timestamp: May 01, 2014, 01:19:39 pm
content: I know, no warranty on them not leaking at all. Funny enough if I buy an Energiser brand, or the Ever Ready brand batteries ( next to each other on the shelf at Wallyworld) they have a price difference, but the cells look the same apart from the wrapper, and the stamped or printed batch numbers on the cells are identical down to character defects, and the packaging is identical size and blister wise, with identical stamps for production lot on them. I have been buying the cheaper ones as the most common use I have is for clocks at work.

author: dexters_lab
author_rank: Unknown
timestamp: May 01, 2014, 01:33:42 pm
content: defo prefer AA size now, pop in a couple of energizer lithiums and you wont have to worry about batteries for a loooong time.never quite understood why the 9v PP3 style battery is always so expensive

author: SeanB
author_rank: Super Contributor
timestamp: May 01, 2014, 02:51:39 pm
content: PP3 battery is essentially the same price as 6 AAA cells, as they are essentially a convenient package with 6 AAAA cells inside. Major advantage is the extra layers of sealing so that a leaking cell has a lot more protection from corroding the equipment, though the packing density and energy stores is a lot less. The plate style ones as well are essentially dry, so do not leak easily, but have a very high internal resistance.

author: XOIIO
author_rank: Super Contributor
timestamp: May 01, 2014, 03:03:02 pm
content: Quote from: SeanB on May 01, 2014, 02:51:39 pmYeah, I haven't seen nor heard of a 9 volt leaking yet.Also, didn't know PP3 was a term for them, does it signify the cell configuration or something? I bet if you went to a store and asked for one nobody would know what you are talking about.

author: SeanB
author_rank: Super Contributor
timestamp: May 01, 2014, 03:27:57 pm
content: IEC size, you get 2 common sizes that are 9V, PP3 and PM9, with PM10 being the less common version. Basically small, medium and large. The PM9 and PM 10 are mostly sold for use in portable radio's as a relatively long lasting power source. Though I have bought a few of the radios I always made up a mains adaptor, as the PM9 batteries actually cost more ($3) than the radio cost ($2), and I needed some radios for staff at work. Cheap radios, cheaply built ( 10V capacitor throughout, and they probably regard Capxcon as a premium brand) but they do work well enough, having at least not terribly bad audio.

author: BravoV
author_rank: Super Contributor
timestamp: May 01, 2014, 04:13:26 pm
content: Quote from: XOIIO on May 01, 2014, 11:23:18 amHow about eight AAs ?

author: XOIIO
author_rank: Super Contributor
timestamp: May 01, 2014, 04:18:02 pm
content: Quote from: BravoV on May 01, 2014, 04:13:26 pmHoly hell.That's not just a multimeter is it though, with that massive display. I'd almost guess a portable osciliscope.

author: BravoV
author_rank: Super Contributor
timestamp: May 01, 2014, 04:39:32 pm
content: Quote from: XOIIO on May 01, 2014, 04:18:02 pmLol ... not a scope, its a LCR meter.But if you want to check out which DMM is using your favourite battery sized/form, check the popular stickied thread ->Multimeter spreadsheetcreated by Wytnucls.Agilent U1242B uses four AAA cells.

author: calexanian
author_rank: Super Contributor
timestamp: May 01, 2014, 06:13:30 pm
content: Another vote here for the 9 volt based on the fact that their leakage is generally contained inside and does not foul the meter contacts.

author: steve30
author_rank: Frequent Contributor
timestamp: May 02, 2014, 03:11:54 am
content: I'm not too fussed.My main multimeter is powered by 6x 'C' cells. That lasts quite a long time.I have a portable multimeter which is powered by 6x 'AAA' cells. I generally prefer AA to AAA, but they do last a reasonable time, so I'm not complaining.My old cheap multimeter is powered by a PP3 battery.All seem to work well.

author: mariush
author_rank: Super Contributor
timestamp: May 02, 2014, 04:04:41 am
content: Quote from: 3roomlab on May 01, 2014, 04:20:14 pmBe careful with powering multimeters from usb on the computer, computer and usb is NOT isolated (it's not a floating 5v) so you can damage your usb port/motherboard/computer if there's some fault in the multimeter and it's just not a good idea to run the meter like that. By default, the battery makes the meter floating so all's good, with computer usb you don't have that.Use an isolated dc-dc converter (murata, recom etc ) that basically use a transformer to convert 5v usb to 3.3v - 5v isolated then boost to whatever is needed to keep the meter happy and not show battery low.Or, use ICs likeAdum5000which for example gives you 5v @ 0.1A with just the chip itself, no transformers required.

author: SeanB
author_rank: Super Contributor
timestamp: May 02, 2014, 05:03:24 am
content: Plenty of rechargeable cells leak with age, and most will leave KOH electrolyte residue which will corrode copper very well. Nice thing is that it is easy to neutralise with vinegar, then a wash with soap and water.