Digital caliper battery drain prevention
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- เผยแพร่เมื่อ 17 ต.ค. 2024
- Digital calipers are a great tool, and very inexpensive to buy. Unfortunately, they all seem to have a common problem - excessive battery drain. I had some that I wasn't using because it was a pain to keep removing and reinserting the battery every time, so I decided to modify them with a physical switch to isolate the battery and mimic its removal. Not everything went to plan though.
Outro music: Calvary by TrackTribe
I have a Fluke DVM that I used for work back when I was a computer technician. It was given to me as part of my tool kit.
I stored it in my tool bag. That job ended in 1990. Last month, I found the toolbag after a move to a new home. I opened it up, and there was the Fluke. I turned the switch to AC volts, and it immediately powered on! 33 YEARS later! I was astounded, and wondered if it was nuclear powered. 😊.
Nope, I had to unscrew the back, and found a simple 9V battery. I am still amazed.
Wow, good deal. Clearly it wasn't a Duracell ;-)
I've been wanting to do this for a very long time. Glad to see what is involved. Thank you for doing the work!
Nice. My "solution" to this has always been to put the battery in upside down when not in use, but this isn't infallible as you inevitably forget. I ended up taping an AA battery holder with built-in switch to the back of it, and soldered the wires of this to the battery terminals. Inelegant, but it works and the larger battery lasts a good long while (roughly 20-30 times as long even if left switched on, and the battery can be recharged).
This is a much nicer idea - the manufacturer should introduce it themselves.
I bought a cheap Parkside digital caliper from Lidl 3 years ago. Use it almost every day, never changed the battery.
I am very positively surprised by that caliper.
I think I paid $7-8 for it.
Thx for the video.
the calipers that use the 3v lithium battery don't have this problem.
If you have access to a 3D printer (personal, buddy, local library, etc) there are some designs on the various 3D model repositories that provide a mechanism to slide a thin bit of plastic between the negative battery terminal and the battery. These typically come in three pieces and require the caliper's board to not have any parts between the data connections and the battery terminal. One piece is the slide with a thin section on one end (typically 1-2 print layers thick for a 0.2mm layer height) and a handle at the other end. One piece is a guide for the slide that fits inside the caliper. And the last piece is a replacement door for the data port cover with a slot for the slide. In use, you pull the slide up and the battery contact can touch the battery. When done using the caliper, press the handle down to disconnect the battery. I use this on my El-cheapo brand, but as I recall I did have to trim the guide a little after printing to fit in my calipers.
Bought one of these cheap digital chinese calipers on 2022 and after having changed 4 batteries during two years I convinced myself to try modding it and install a physical on/off switch.
Had everything done: necessary traces cut on the pcb, on/off pad isolated, plastic trimming...just to find out that 5 minutes after reassembling everything the lcd screen made a "pop" sound and broke itself, most likely because of excessive pressure of the on/off switch against the LCD.
I bought another one recently which in theory looked the same model, but found that pcb had changed (no longer LF silkscreen) and so did the lcd model and the case, making it even cheaper with less screws.
I was able to do a mashup of both calipers to avoid having to cut plastic on the new case and after adapting the lcd ribbon, foam cushion and sanding a bit the on/off switch, this time it worked as it should.
My advise is that if you need a reliable caliper, consider buying a quality one and consider the amount of time and frustration these cheap ones come with if you want to avoid battery drain.
Agreed. If I used one more often I'd definitely buy a Mitutoyo, but I can't personally justify that cost. Even then you have to be careful of the fake ones.
Awesome video. I have a couple of calipers like these and I have been suffering the same problem. Great mods. Man, that first mod got complicated and seemed like it was a pain. But you're right, it looks really good.
That is some other level tinkering. Fantastic job!
What I did was harvest a 3.7V to 1.5V step down PCB from one of those USB-C rechargable AAA batteries. The PCB and a slider switch were JB Welded to the housing and a tiny 180 mAh lipo battery was attached using double-sided tape. I can recharge it via USB-C in 10 minutes. Ugly but functional. No more button cells for me :)
Where did you get that small switch? Thanks, great video!
I got them from Amazon UK: www.amazon.co.uk/dp/B01NCYTRRO?ref=ppx_yo2ov_dt_b_fed_asin_title
i wonder if a magnetic read switch might work better. You hold an external magnet to the location of the reed while you want the calipers to work. I agree, every time i go go use my calipers, the battery is dead. horrible design.
I like the reed switch idea. Perhaps use it to cut power instead of provide power, then you could build the magnet into the case.
I hot glue a AAA battery on the back of the calipers, and run a pair of wires in through the battery compartment lid. Works for a few years, with no user input required. Not as neat, but less work.
lol, did the same :)
I highly recommend those extended narrow tip's you can put on the superglue bottles. I have had great success with the superglue (especially the thin) going where I want it vs all over...and instead of the bottle being a pain to open the lid on, it stays almost totally clean after even using half a bottle. I will have to keep this fix in mind if I have more issues with my digital caliper.
And you can reuse them if when you are done and take them off you blow air from like your compressor through them to clear out any remaining.glue. ie tap the glue down into the bottle, take the top off then use an air hose to blow the rest out somewhere it won't cause issues.
The Calipers supplied under Insize brand and Moore & Wright brand use a larger diameter 2032 coin cell which is 3.6 volt and lithium chemistry. They seem to last a lot longer than these cheaper types that use a LR44 button cell. There is also something else you should read up on the recommendations to use a SR44 silver oxide cell rather than the LR44 type for digital micrometers and calipers. The SR 44 type retain their voltage much longer than the LR44 type.
Thanks for the info. I checked on Amazon, it appears that the SHONSIN and Kynup brands also use CR 2032 batteries.
Thanks for sharing! Might do this to mine!
Oddly, I have the ostensibly same HF "Pittsburgh" calipers, and though I don't use it every day, I certainly do multiple times per week, and the batteries in mine last for years. I'd love to know what's different. Hmm, it's probably down to the fact that mine does not store and continue to track it position when off. Which is not a big deal, you just rezero.
I bought the same caliper from aldi, yep its a vampire lol.
Not bad for the price though.
The $9 cheap one from Walmart (Hyper Tough) does in fact drop the current from about 20 uA to about 1.5uA... and thus will not drain the battery much when off. My other 4 digital calipers only drop from about 20uA to about 15 uA when off. Maddening that the cheap one, with all cheap feeling parts and no lock nut, is the only one I keep handy since it does not eat batteries...
it's by design. when it's off, simply sliding the caliper powers it on. It has to draw power to do that.
Whether that's a flaw depends on your point of view - but it annoys the hell out of me :-)
I hot glued a AAA battery holder with an on/off switch on the reverse side and ran the leads through the battery door. Button cell batteries are ridiculously overpriced.
Next time use a tiny toothpick or a needle for clothes, a tiny micro drop will be way more than enough.
Instead of pouring it straight out of the bottle.
And apply it with the toothpick or needle on the switch.
To glue it in Place.
What an absolute shit-show 🤣
Jokes aside, this was a lot more involved than I thought it would be. Thank you for showing a bunch of potential pitfalls. I'm sure I'll discover some new ones when I give this a shot.
Well done figuring it out in the end 👍🏻
Subscribed.
Someone just did a comparison of fake and real Mitotoyo calipers. The fake ones have the same issue.
Making real Mitutoyo worth every penny. My batteries last years and I use calipers almost daily.
It would cost the Chinese $0.01 to add a proper switch and make a proper product. So they don't.
Buy a set of Brown and Sharpe dial calipers. Problem solved.
$250 is a bit much if you're just a hobbyist.
@@onecalledchuck1664 True, l'm a Tool and Die maker. It's pretty much Brown and Sharpe and Starett in my arsenal.