Power contactor for PV string

[BackyardBandit]

Hello all, first post as a new member, longtime lurker.

Does anyone know of a solution for reducing the size of a PV string (in series) using an AC-coil power contactor/relay? A part number would be fantastic.

The objective is to isolate a string of panels down to just three panels to charge an Eco-Flow Delta PRO portable battery using existing rooftop solar from a grid-tied system. The relays would be energized during grid operation and de-energized during off-grid operation. Drawing attached.


Thank you in advance for any assistance you can provide! If anyone knows of another workaround or see any glaring problems with this silly idea, I'd be happy to hear them!

 

[timselectric]

Those relays (if available) would be too expensive.
A lot cheaper to buy panels for the other charger.

 

[efficientPV]

The second set of contacts is unnecessary and put a diode connecting GTI panels which are left to reduce open circuit voltage.

 

[BackyardBandit]

Those relays (if available) would be too expensive.
A lot cheaper to buy panels for the other charger.

True, I hadn't considered that. Added cost probably isn't worth the tiny amount of convenience you'd get out if it.

 

[efficientPV]

You can run some AC power supplies directly from the DC of the panels and have compete isolation.