Multi Plus II

**Rich38** · 01-16-2023, 01:20 PM

Finally bit the bullet and installed the Victron 12V Multi Plus II in my 351M over the weekend. Everything went well, very challenging working with 4/0 battery cable. The 6/3 was by no means easy as well. Tested in the driveway and everything seems to be working good. Going to Quartzsite this coming weekend to give her the big test. I have one question. When hooked up to shore power, should I get shore power through the inverter with the switch off? I can only get shore power in if the inverter switch is set to ''charge only'' or ''inverter on'' ? I thought ''pass through'' meant shore power would pass through the inverter with it in the off position.

Thanks for the help.

Rich

**A.Texas.Yankee** · 01-16-2023, 02:09 PM

Originally Posted by Rich38

Finally bit the bullet and installed the Victron 12V Multi Plus II in my 351M over the weekend. Everything went well, very challenging working with 4/0 battery cable. The 6/3 was by no means easy as well. Tested in the driveway and everything seems to be working good. Going to Quartzsite this coming weekend to give her the big test. I have one question. When hooked up to shore power, should I get shore power through the inverter with the switch off? I can only get shore power in if the inverter switch is set to ''charge only'' or ''inverter on'' ? I thought ''pass through'' meant shore power would pass through the inverter with it in the off position.

Thanks for the help.

Rich

The internal switch will close when in the off position, not allowing pass through of AC input. So that is correct operating to not ha e AC input pass through.

**Rich38** · 01-16-2023, 02:12 PM

Thank You Sir for the info and confirmation.

Rich

**A.Texas.Yankee** · 01-16-2023, 02:14 PM

Originally Posted by Rich38

Thank You Sir for the info and confirmation.

Rich

One of the reasons I never touch the physical switch and just use the victron app/portal.

**WondersAwait** · 01-18-2023, 11:04 AM

Welcome to the Multi-plus II crew! It's a beautiful piece of electronic technology. We love ours.

**Brother_Bluto** · 01-21-2023, 06:51 PM

Would you mind posting pictures of your install? Have been putting off installing the MP-II in our 351M for too long and over analyzing placement, etc.

**SolarPoweredRV** · 01-22-2023, 03:37 AM

Originally Posted by Brother_Bluto

Would you mind posting pictures of your install? Have been putting off installing the MP-II in our 351M for too long and over analyzing placement, etc.

One thing that really helped me with my install was creating a cardboard template. I knew I needed to install a plywood backer board in both holds to mount my equipment. So, what I did was, decide on the max size backer board that would fit in both areas and create a cardboard template that matched the plywood cutout.

I then took each piece of equipment (except for the Inverter) and laid them out on the cardboard template to decide exactly where each device was going to fit and how I was going to route all my cabling. Once I had the final layout, I took photos for reference while I installed the whole system. This really saved me a lot of time once I began installing everything and made the layout as efficient as possible.

Hope this helps you to move your project forward.

**xxn5ac** · 01-23-2023, 10:02 PM

I installed a MPII, 2kW of solar panels and 10.4kW of lithium batteries in my 390RK and I couldn’t be happier. I did it mainly for boondocking and so I can camp in the spots with no electricity, but I have a benefit I didn’t predict: when I can only get a 30A circuit, my trailer behaves like a 50A system. I can run everything in the trailer and when AC cycles off, the batteries top back off. It’s a wonderful thing!

**Ynot4me2** · 01-24-2023, 10:53 AM

Originally Posted by xxn5ac

I installed a MPII, 2kW of solar panels and 10.4kW of lithium batteries in my 390RK and I couldn’t be happier. I did it mainly for boondocking and so I can camp in the spots with no electricity, but I have a benefit I didn’t predict: when I can only get a 30A circuit, my trailer behaves like a 50A system. I can run everything in the trailer and when AC cycles off, the batteries top back off. It’s a wonderful thing!

That's an impressive system. Would love to see a pic of your battery bank ant roof.

**Rich38** · 01-25-2023, 11:52 AM

Back from my first test in Quartzsite Az. For as small as my system is, I was happy with the performance. Going into this project my main goals were to have a few cups of coffee in the morning, watch satellite TV and be able to charge our cell phones. The weather was pretty cold so the heater ran quite a bit during the night. Most mornings my Renogy battery monitor showed 82% SOC. When the percentage dropped to about 71% and I was using the coffee maker, the Victron remote switch would light up the red LED for ''low battery''. A little confused why it would do that if I had 71% battery power left? Still much to learn.

I have attached a pic of my install on the 351M. It's tight, but is working for me.