Victron MultiPlusII and Lynx DC Distribution System

[sackettd]

I'm excited about our June 12th pickup of our new Escape 19! I decided to have ETI install 2 solar panels and lithium battery ready and I would install the rest.

I am seriously considering a Victron Multiplus and Lynx DC Distribution installation. I would be hugely thankful if anyone familiar with these components, or any of our knowledgeable members, would take a look at the diagrams I have created. They are obviously not official wiring diagrams, but I'm hoping people may find errors or omissions or have suggestions.

My electrical knowledge is limited: I did a new lithium battery and cabling install for a trolling motor last year and installed a solar port and controller for my Casita also last year. This forum has been hugely helpful as I have researched threads and had a member provide detailed information and images of his recent E19 electric build. Thanks David!

I was intrigued by the Victron MultiPlus and Dc distribution system. It will set me back roughly $1000 more than if I used other components, but it appears to make the installation much simpler and having almost all Victron components is apparently top of the line.

My feeling is I will be saving roughly $3000 with the parts I am installing compared to the $9000 Escape charges for a similar system. I could save $4000 without the Victron components, but I feel it may be worth it given my inexperience and the quality of the components.

I decided to make a couple diagrams to see if I understand the installation. I have not included fuse sizes. The Lynx system uses Mega fuses in the components. I will definitely be researching fuses to choose the correct ones.

Is it true that in this installation I can use the WFCO Power Center to manage the 110 and 12 volt circuits out to the trailer if I disconnect/remove the WFCO converter charger?

I have a preliminary wire gauge size list:
-Battery 2/0
-Solar Chargers and DC-DC Charger 8 gauge
-DC Distributor to Multiplus 2/0
-DC Distributor to DC input on the MFCO Power Center 10 gauge
-Lynx shunt 8 gauge?
-Possible DC fans from Distributor, 10 gauge
-the Lynx components are modular and connect together directly

I need help understanding grounding. I think the WFCO Power Center has a ground wire installed already. Do I need to add additional ground wires?

Thank you!

 

[sackettd]

Driver and passenger side diagrams.

 

[oldwave]

Driver and passenger side diagrams.

The Multiplus replaces the wfco. Use the Lynx to connect to the multiplus, the dc loads and the battery bank. On my bigfoot I have a fused connection from the lynx feeding the dc panel, a second connection feeding the emergency brake circuit and the tongue jack. I also have a shut off after the lynx for the panel feed (servo conttrolled but a manual one will work.
I also have a fused connection with a manual shut off from the battery banck feeding the Lynx. Its an Excellent system and you can size the fuse for the dc loads.

The multiplus calls for a large ground wire to the frame, I used a 1/0 with 2/0 feeding the multiplus.

 

[Chamberman]

My question is, where will you install the Multiplus II in the manner that it was designed to be installed? This unit is 22" x 11" x 6" and requires 4" of open area on all sides. Its designed to be mounted vertically on a wall according to the manual. In other words, vertically with the cable connections facing downwards.

Looking at our own E19 I can only see being able to mount the Multiplus horizontally. So I'm going to assume you plan to mount it in this manner. If so, this is not optimal and will cause it to run warmer than normal. The Victron IP22 charger I installed uses an integral heatsink which allows for convective cooling with low loads when mounted vertically. There's a fan in the IP22 (same as the Multiplus II) and it ramps up in when loads and temps rise. Mounting the unit horizontally means that the fan will run longer and at higher speeds and may even be intrusive, especially at night.

 

[Centex]

My question is, where will you install the Multiplus II in the manner that it was designed to be installed?

 

[oldwave]

My multiplus is indeed mounted horizontally with plenty of space for cooling. I also installed a couple of fans one pointing at the top of the unit and another on a vent to exhaust the heat. My unit was fine through the summer heat last year. The only time the fan ran was when the battery bank was very low from a long drive running the fridge on the inverter and little sun. If you read the manual the ideal
Is vertical mounting but it does allow for horizontal mounting also. I have Ruuvi tag sensors in my compartment to monitor the temperature. Plus another sensor that I can program the fans to come on .

Like any electronics heat management needs to be considered. There are inverters that you can mount on the floor, PD 2000 watt comes to mind. I like the Victron ecosystem and so far the reliability has been stellar. The fans never come on with normal dc loads by the way, only when a strong charge is needed.

 

[Chamberman]

If you read the manual the ideal
Is vertical mounting but it does allow for horizontal mounting also.

Like any electronics heat management needs to be considered..

The current Multiplus II manual doesn't say anything about horizontal mounting. I did a quick search and it looks like the manual from a few years back used to have wording that allowed for horizontal or vertical mounting, but Victron altered the text and removed the statement that said horizontal mounting was allowed. They point to appendix (G) but that appendix shows dimensions and only displays the unit standing upright.

The current manual states,

The MultiPlus-II is suitable for wall mounting. A solid surface, suitable for the weight and dimensions of the product must be
available (e.g., concrete, or masonry). For mounting purposes, a hook and two holes are provided at the back of the casing (see
appendix G).

The old Multiplus II manual stated,








I agree with you on the subject of heat management and would also consider installing an exhaust and auxiliary fan if mounting this unit in a horizontal position and with limited space inside of a tight cabinet.

 

[oldwave]

pics of install

Here is a picture of my batter compartment under the seat. The fan assembly is featured on the second image. I had a 3d printed mount made to match a standard RV furnace vent.

 

[Chamberman]

Here is a picture of my batter compartment under the seat. The fan assembly is featured on the second image. I had a 3d printed mount made to match a standard RV furnace vent.

Looks like a very nice installation. I like the angle bracket mounts for the MPPT and DC - DC charger (I'm guessing).

 

[oldwave]

Looks like a very nice installation. I like the angle bracket mounts for the MPPT and DC - DC charger (I'm guessing).

Correct I had my machine shop make them up for me for optimum cooling. The big fan is a bilge fan and is controlled by a rheostat on the floor other wise its like a jet engine. The small black circle is the Ruuvi tag temp sensor. I have the Multiplus, not the Multiplus 2. Though I am considering an upgrade.