Is your charger BOOBY TRAPPED? Why you need a Multimeter!

Thomas Jaszewski

Well-Known Member
Could your charger be made specific to your bike and th polarity reversed? I just read a stunning Paragraph in an industry publication for resellers and shops.

"Battery chargers are also not cross compatible. It’s good workshop practice to make sure that all the chargers are labelled as to what battery/bike they are for. For instance, a manufacturer may choose a stock charger body, but to make it specific for their brand of battery they will switch the poles of the charger, which could lead to devastating results if used with the wrong type of battery."

Another reason I preach owning a inexpensive digital auto off multimeter. A multimeter will tell you if the poles are reversed. Touching the probe to the leads will show a minus sign "- " If you are touching reversed leads.

There are so many good reason to own one and so many easy tests that can be done at home from sorting the brake cutout to seeing just exactly what your pack voltage is. And much more...

$20 delivered! https://www.amazon.com/Multimeter-A...8-2&keywords=digital+auto+off+multimeter&th=1
 

Mr. Coffee

Well-Known Member
I'd agree that if the polarity, voltage ratings, current, and connectors are compatible and if you are using a non-stock charger with a given battery it (the battery) is unlikely to explode. Beyond that I'd not be one hundred percent confident.

Keep in mind that both the "charger" and the "battery" are actually computers that communicate with one another with respect to how best charge the batteries in the "battery" and what is the optimum current delivery from the "charger". One way to do that would be to put nearly all of the smarts in the "battery" itself. But that isn't necessarily the only way that it could be done. Manufacturers of batteries and chargers aren't very interested in sharing those details with regular folks.
 
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Thomas Jaszewski

Well-Known Member
Keep in mind that both the "charger" and the "battery" are actually computers that communicate with one another with respect to how best charge the batteries in the "battery" and what is the optimum current delivery from the "charger". One way to do that would be to put nearly all of the smarts in the "battery" itself. But that isn't necessarily the only way that it could be done. Manufacturers of batteries and chargers aren't very interested in sharing those details with regular folks.
Thats really not accurate for most systems. I think some manufacturers do a diservice making these systems mysterious "computers". Those that have made their systems, battery and motor, interdependent seem to be taking a hit with some of the better bike builders. A battery BMS really is a fairly simple device and a vast majority have no link or direct communication with the charger.