Series-wired voltage checks

[ranger58sb]

Have just read in another forum that, given a 3-battery 36V bank of 12Vs wired in series... (trolling motor application)...

A voltage measurement from the pos/neg terminals of any single battery in that bank will be 12V.

And that a measurement from Batt 1 Pos to next-in-line Batt 2 Neg (for example) would give 24V.

Didn't think voltage measurements for batteries within a bank could be isolated like that... but then I've never had a series-wired bank right in front of me to learn with.

??

-Chris

[jeepbluetj]

Sure it can. And it's useful if you're tracking down a bad or poor performing batt in a series wired string.

If you had a giant stack of D-cells, you could measure any voltage between any combination of batteries - one battery would be 1.5v, 2 would be 3v, etc....

You don't always measure voltage to ground, it's just the potential between 2 points.

[StuM]

If you cracked open the top of a single 12V battery, you could do the same thing with the six individual cells inside. Each one should be between 2.1V ans 2.4V, each pair between 4.2V and 4.8V etc.

[ranger58sb]

Very useful to learn, thanks guys.

-Chris