question

George Napier avatar image

Wiring 150/50 to battery

Hi, I'm connecting a new smart solar 150/50 to my batteries (12v 1800a/h lead acid). Does it matter which order the cables are connected? +ve or -ve first? Thnx for advice ;-)

wiring
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3 Answers
Daniël Boekel (Victron Energy Staff) avatar image
Daniël Boekel (Victron Energy Staff) answered ·

Hi @George Napier

It's best to always connect minus first, and have all switches / fuses / etc. in the positive lines.

this way you prevent that any communication wiring can have current flowing through it when a negative wire is not connected.

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George Napier avatar image
George Napier answered ·

Thnx for tips...hadn't actually contemplated a fuse between the +ve battery cable and the charge controller. I've actually got a 50A fuse/holder spare: would that work for the battery/controller I've got?

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warwick avatar image
warwick answered ·

I know when it comes to automotive, positive should be connected first because negative is grounded to the body.

If the negative is connected first, a spanner shorting against the body when connecting the positive could damage the battery, cause fire or injury.

But, in the case of a solar / battery setup, even bus bars, I can’t think of any practicalities that would prefer one over the other.

That means we need the electrickery gurus to advise whether there is any difference connecting one before the other.

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