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Charge Controllers and Clippers => The "Classic" charge controller => Topic started by: jta on July 22, 2026, 11:22:49 AM

Title: Classic150... can it fail and pass-thru PV voltage to battery-bank?
Post by: jta on July 22, 2026, 11:22:49 AM
I've got a Magnum 4024, pre-wired with MidniteSolar E-panel & Classic 150. Over at this forum, there is an unverified case of a Victron 12v MPPT "failing" in such a way that PV voltage got passed-thru to battery.

Details in first post on thread at:

diysolarforum.com/threads/solar-charge-controller-failure-leading-to-lfp-fire.127623/

My Classic (and the whole pre-wired system) has been flawless for well over 5 years (past it's warranty period), so I'm very happy.

But, I'm not sure if either the classic 150 has "isolation" (correct term?) or e-panel would prevent this scenario? I searched the classic user guide, but "isolation/isolated" didn't come up in such a way as to explain this scenario ...

Any thoughts?
Title: Re: Classic150... can it fail and pass-thru PV voltage to battery-bank?
Post by: ClassicCrazy on July 22, 2026, 11:44:24 AM
In the many years on this forum , I have never heard of a Classic failing in a way that will pass PV voltage directly to batteries.
The Classics have been around for a very long time.
They are not isolated in that the negative is shared by both pv and battery .
Larry