Duracells How does the so -called capacity feature work ?

[Myron Beaumont]

Someone must know how it does or does not work amongst us . Could be very handy for us couldn't it with our rechargeables?

[WolstonFlyer]

Doing a quick search on the www...

"The powercheck guage is a resistive strip stuck on the side of the battery and when you press the 2 white buttons you complete a circuit.

Depending on the state of charge of the battery, current flows through this strip (which is coated with a varying band of temperature sensitive chemicals), and as it heats up the chemicals change colour.The higher the current flow, the more of the chemical changes colour, and so the higher the guage reads"

[Simon Chaddock]

They use both a conductive and thermochromic ink.

When you press the dot it completes a circuit and the current flows through a strip of conductive ink and it heats up. By changing the printed shape of the conductive ink the length of conductive ink that warms up can be made proportional to the current, so the better the battery the more of the strip warms up.

A layer of theromchromic ink is superimposed on the conductive ink so it changes colour as it warms up.

Cheap and cheerful rather than accurate.

Technically its measuring the effect of a current so I am not sure it would be very useful on a LiPo cell.

[Wasaforumite]

And every time you use this feature you drain the battery a little bit more.................

[Peter Beeney]

Myron, - It’s just a voltmeter with the reading given in capacity. All the radio kit has voltage indicators, too; a voltmeter on the tx, and you easily install an on-board voltage monitor, (a voltmeter), on your model to measure the remaining capacity for any type of cell, Nickel, LiFe or LiPo. I have tried these for suitability of purpose, at least to my own standards, and I’nm convinced these are excellent items nowadays. They were a bit suspect in the past, but now vastly improved.

And for reasons I’ve related in past threads, I think this is the single most important device on my model, when it’s missing I can never say for certain sure the exact state of charge of the receiver battery. Which, in some circumstances, can be extremely ‘striking’, to say the least. Models with no power are uncontrollable, and will crash anywhere, there is no disputing that fact!

As a voltmeter, the capacity indicator on a Duracell is definitely not a top class item, probably not even any class, so you really wouldn’t want to use anything like this on your model.

PB

Edited By Peter Beeney on 26/12/2012 22:49:11

[Martin Harris - Moderator]

Posted by Peter Beeney on 26/12/2012 22:48:15:

And for reasons I’ve related in past threads, I think this is the single most important device on my model, when it’s missing I can never say for certain sure the exact state of charge of the receiver battery. Which, in some circumstances, can be extremely ‘striking’, to say the least. Models with no power are uncontrollable, and will crash anywhere, there is no disputing that fact!

I'd agree that receiver battery voltage monitoring is of paramount importance but to go a step further, it's the most useful feature of telemetry - and something that (literally) shouts at me if at any time during the flight the voltage drops for any reason such as unusual loads from a stalled servo - or as happened a few weeks ago, a cell failure in flight, neither of which can a conventional monitor alert you to.

[Myron Beaumont]

Thanks to you all. I don't use them myself but its just nice to know how the system works.Just my enquiring mind . Now I can pretend I know all about them in conversation with less intelligent non-modelling types