View Full Version : Switching to a VSR from the factory isolator?

06-21-2014, 02:08 PM
Anyone switch over to a Blue Sea VSR from the factory isolator?

Did MC switch to VSRs in 08?

06-22-2014, 07:44 AM
Well I'll let you know how it goes.

06-22-2014, 08:36 AM
I installed the "add a battery" kit about 4 years ago. Still working well. Very happy with it.

06-22-2014, 12:23 PM

After reading the Xstar wiring pdf that a member was nice enough to share, I noticed there were some changes in 07, and 08-14. Mainly the change from isolators to VSRs and moving the bilge pumps and radio memory wire to direct feeds that work even with the battery switch in the off position.

I'm not too concerned about the memory in the radio. But, since we started camping I've been leaving the boat in the water overnight unattended. In my 06, with the switch in the off position the bilge pumps get no power and I don't like that idea. So I figured I'd get off the isolator, factory guest isolator look a little weathered, and get onto the new VSR and new style switch.

07-19-2014, 04:09 PM
So I finished up my trim tab gauge move and it is raining today. So, figured I'd use the time to finish up my isolator to VSR install.

The only real change, other then the VSR and new switch, was moving the alternator wire from the isolator to one of the batteries.

The switch is different in that my old one was an off,1,2,both and the new on is just an off, on and it does have an emergency combine.

First thing I did was draw up a wiring schematic. I read a lot of stuff about duel batteries with a VSR and it seems a little less confusing then an isolator. That fact comes from how many different ways people install isolators. The only real issue with VSRs is which battery to run the alternator wire to. The two major thoughts were keeping the starter battery fully charge by attaching the alternator wire to the starter battery. The other school of thought was, the house battery gets used more so you should attach the alternator wire to the house battery.

The conclusion I came to is that it really doesn't matter when using the Blue Sea SI-VSR. That's because as long as your alternator is putting out 13.7 volts the circuit is closed and both batteries are being charged. The nice thing about this VSR is that it can vary the charge to either battery by it's need. IE, it can send 7 volts to each battery or, if, one battery only needs 4 volts it can send 10 volts to the other. Some of the other VSRs that I read about cap out at a voltage level.

The other thing I did with this was take out the 1/2 king star board and make a new panel out of 3/4 inch star board. The old panel had a ton of old holes and I wanted to back mount the new switch for a cleaner look. Besides, I had the better part of an 4'x8' sheet from another project.

Anyway on with the show. I hope it will help others.

My diagram: I intend on adding the starting circuit wire, its just not in the schematic.


Mock up of the panel.


Wire routing check:


In the end I went from this mess:


To this:


The VSR and all the circuit breakers are on the back of the panel now.