Newbie replacing PWM solar controller with Victron 100/30

DIY
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1

I bought a used RV with three solar panels and simple solar controller. I have purchased a Victron Smart Solar 100/30 to replace it. Attached is a portion of the schematic from manual for the rig, plus my sketch of what I want to do.

The existing controller has only three wires, battery positive, battery negative, and PV. I plan to use the existing PV wire to connect to positive of the Victron PV connection, and the existing negative wire to connect both the PV and battery negatives on the SmartSolar.

My question is can I connect the negative side of solar panels to the negative side of the batteries, along with the negative side of the smart solar output battery connection.

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You will probably want to rewire the 3 solar modules in series for use with the MPPT charge controller. Also, only one connection is needed from B- to battery negative bus for the MPPT, as the PV- is internally connected to that terminal. The PV negative can also be connected either to the Battery negative bus or to the PV-ve on the MPPT.

3

Thanks Mike!
Especially for the info about internal wiring of the two negative points.
I’m going to start out keeping the parallel panels to make a more valid comparison between the previous and new charge controllers. After some experience with them parallel, I’ll switch to series to make that comparison.