The Hobbyking Cell Key cell checker is a quick and easy way to check your Lipoly batteries before or after use. Simply connect the balance plug of your pack in to the pins on the Cell Key and it will display individual cell voltage for up to 6 Lipoly cells then the total voltage of the battery pack.
Doubling as a key ring the HobbyKing Cell key goes where you do so you will never be caught out without a cell checker again!
I also got the problem where the 6th cell displays a too high value, have validated against both my iChargers. All cells say 4.20 but the 6th displays 4.28 when it according to both iChargers should read 4.20
The negative (common) pole on this charger is really hard to see (its a small yellow "-" on the yellow background of the plastic casing). Use a black permanent marker to color the plastic around that pin - and its easier to hook up right on the go.
I blackened my ground pin as well, but really if you always hold it the same way (upright numerals) with the same hand and plug going the same way, your habit will make the marking irrelevant in a couple uses.
If you have a digital charger, it's readout should be accurate. If not, recalibrate it! If you don't have a digital charger, take your $3 brick outside and hit it with a hammer. Those things DESTROY innocent batteries, and should be punished. Then go get a good AC6 for $15 or so on here...
Over the course of a week this cell checker has lost its accuracy. From the readings, it looks like values for cell 6 have increased by about .15v and cell 5 decreased by .15v while cells 1 to 4 being off by about /- .02v. The total voltage accuracy doesn't seem to be affected though.
That doesn't make sense... it's a calculator, so once it has numbers (even wrong ones), it has to add them correctly. If the cell readings are wrong, the total will be too unless the inaccuracies are perfectly balanced.
This is a great accessory but use with some common sense. I measured the same 3S fully charged LiPo with my DMM and the two HK cell readers with the following results -
Total - 1 cell - 2 cell - 3 cell.
DMM 12.56 - 4.21 - 4.17 - 4.18
Plastic Cell Key - 12.5 - 4.21 - 4.18 - 4.18
HK Battery monitor- 12.6 - 4.20 - 4.18 - 4.23
And my HK charger gives slightly different readings for the three cells. Actually these are all good readings if you understand that there can be some small inacuracy in the voltage readings.
It is not recommended to leave it on the battery during the flight. This is very useful to check the individual voltage and the overall voltage of the battery before and after the flight. with this cell checker, you can determine how many minutes you can safely use your lipo without over discharging the battery.
It is not needed or was designed to be an on board voltage readout. Although if you wanted to you can. if you choose to, i would say remove the yellow housing and use just the board with double sided tap. if you can get a thin piece of smoke color transparent tape to place over the LED readout, the visability becomes cleared. But again, it was only designed as a fast readout of your batteries to provent the use of batteries that have been already used or is to low of voltage to use to provent ri
a portable instrument for measuring the voltage apperativnogo on each battery bank, such as a voltmeter)
it makes no sense to put on the model.
for this is to show the instruments on-board voltage and low voltage on the battery.
the minimum voltage for some components used is somewhere around 3.3-3.4V at lover voltage this unit simply shows nothing - so for checking fully charged 1s lipo is ok (all what i need when working with 1s lipo)
I just got one of these and it only puts out "rd" then "end" like another comment in this list. There is no manual in the box or on-line to look at as was suggested. I have another "unboxed" unit that works perfectly. Not happy at the moment!
www.link the best manual=))) The first number shows the voltage at the first cell, the second shows the voltage at the second cell, and then the total number of =) that's all! and how to connect, see the picture
there is no manual for this cellkey ( as least thats how i got mine, in a little white box with no manual )
try flip the balance plug around, go on my youtube channel at RcJustflight, i have a video reviewing this stuff and how to use it.
instead of thinking of losing the checker, how about thinking when you actually use it?
i guess one would want to take the checker and connect it to the balance connector, right? NOT take a whole bunch of keys (or tx handle or whatever it's attached to) and move it close to the lipo.
Nice little "must have" for the charger box. Easy to use and good precision. Checked with a multimeter and got the same reading to the secound decimal point (0.01) I have it availble with my LiPo packs anytime I am out in the field now.