The cell logger arrived from HobbyKing last Thursday and there ensued a kind of rollercoaster weekend that went from the despair of feeling like I'd never figure out how to wire it in to the euphoria of getting it wired and watching it display 8 cell voltages for each of the 3 plugs I put into it into, back to the despair of accidentally subjecting it to 60 volts of juice while trying to organize and straighten out the wiring, to some short-lived joy when it seemed to work again in some kind of limited fashion, then finally ending in despair when it actually started smoking during one test and the screen went dark and never came back again.
Probably at least 10 hours were lost simply because my personal system of enumerating batteries was opposite of the standard way. For some reason I have always just called the first battery off of the positive terminal battery 1, and the last battery, connected to the negative terminal was 24 to me. So when I tried to follow the cell logger wiring diagram, and connect the negative terminal from cell 1 and the positive terminal from cell 1, as well and the positive terminals of the next 7 cells in sequence, the cell logger wouldn't even power up. At that point I got lost in a sea of confusion that arose from the fact that i wasn't sure if even the little plugs I had constructed were even functional. Or since I know squat about wiring diagrams I had to question whether I had at all correctly interpreted the one provided with the cell logger. or even, did the makers of the cell logger provide a bad diagram (it's coming from China, and the English documentation is terse and often vague and lacks in detail)?
But really the whole thing might have been ABC if I had just understood that battery 1 is connected to the negative terminal, and battery 24 is connected to the positive terminal, and what I really had been doing was connecting batteries 24-17 to the cell logger instead of 1-8. (The cell logger needs to have the first pin of its plug connected into the negative terminal of the first battery of a series, so I was plugging the first pin of the plug into the negative terminal of cell 24 instead of cell 17 in order to get the readings on those 8 cells.)
At any rate, after these mis-steps, all the batteries were displaying on the cell logger around 9 PM Saturday evening, and I left off for the day ecstatic about that. But the next morning, when I woke up, I realized there were these dinky little 24 gauge wires stringing all over the place. In order to organize them better, I had to string some more 14-gauge wire between some of the cells and the euro-style strips so that, any one plug coming from the cell logger could get all the info it needed by sending the little 24-gauge wires out to just one euro style strip at a time for each of the 3 -8cell series of batteries.
The good thing about this is that no battery trays had to be removed -- I didn't need any more 14-gauge wires from the bottom 6-pack of batteries, and the other 18 could be accessed by just removing a metal retaining strip and the charger and a couple of plastic covers from over the tops of the battery cases. Once i did that, I first removed the positive terminal cable that connects to the positive terminal on what I originally thought of as the "first" battery of the pack. I made a huge mistake at that point without thinking very hard about it. There were actually 2 or 3 cables connected to that battery's positive terminal, and I removed all of them and carefully covered them with electrical tape.
The problem was that one of the wires was one of my 14-gauge voltage testing wires that went led to the euro-style terminal strips. So instead of interrupting the current completely, I was just re-directing it into some kind of convoluted wiring system that had 60 volts flowing through it instead of the preferred 0, or the full 90. But the cell logger is only set up to handle 43 volts, so when I hooked it in for a brief test, it made a quick nasty snap sound and went dead for a while. From then on it just showed a "cell voltage error" every time I tried to hook it up, even when I hooked it up to the other plugs that had worked just a minute before.
The cell logger never really seemed the same after that. Even when I powered it up off my computer and navigated the menu system a little bit, it uncharacteristically just blacked out on me after a couple of minutes. Then like I said, during some further testing later on, after I had actually got it to show the voltages of 6 cells out of an 8 cell series, the next time I hooked it up smoke just started pouring out, the screen went black, and it was dead.
I spent a long time after that going over every wire again and again and re-wiring mistakes and checking voltages, and I now think I have all the plugs ready to go, hooked into the euro-style terminal strips, but I have to wait for another cell logger to arrive from HobbyKing. And this time they are back ordered, so who knows how long it will take to get the next one? But I gotta say, it is cool as hell to get the voltages of all 24 batteries by just plugging the little bugger into 3 different plugs, and it will be cooler still if/when I can get it to record the cell voltages twice a second while I am riding the bike full throttle up the long steep hill...
Author
Topic: guity's gpr-s experience (Read 42091 times)