BMV-712 Walnut Stand - 27’ Globetrotter FBT

[jeffmc306]

There are many posts about installing a Victron BMV-712 which inspired me to tackle the project. I wanted to keep it simple without permanently mounting the display in the wall yet still make it accessible.

I also wanted to keep the shunt close to the battery box and minimize longer 4 gauge wire runs. I took the opportunity to remove any rust and paint the interior of the battery box. Since all the negative load cables need to be connected to the shunt, I installed buss bar to aggregate them and send one cable to the shunt.

I envisioned a table top wood stand to hold the display similar to a desk clock. Shout out to Bull Valley Hardwood in Woodstock, IL where I found a nice piece of 5/4 Walnut. They also sell Teak so the shower floor mat is the next wood project!

I cut the Walnut into a 4” square they cut a 20 degree bevel on one side. A 2” Milwaukee hole saw and a little massaging with a wood rasp sized the hole for the display. I routed out the back side enough to fit the threaded ring to secure the display. A little Minwax Aged Oak Gel Stain and the wood matched our AS trim.

The Night Stand between the twin beds was the perfect location for the Walnut stand and display. The challenge was how to get the communication cable from the shunt to the display. I followed the large Inverter cables from the curb-side of the battery box under the trailer and found the entry point.

I removed the access panel under the head of the curb-side bed to see the cable entrance from the belly pan. Using an old bicycle brake cable housing, I fished it from under the trailer next to existing cables into the trailer. I taped one end of the communication cable to the fish and gently pushed it down the cable entrance. I finished the pull from under the trailer and fished it through the protective cover around the Inverter cables back to the battery box.

I ordered a waterproof plastic box from Amazon for the shunt and made a metal base plate to bolt the shunt to then screw the plate to the inside raised posts of the box. A quick coat of Rustoleum Painter’s Touch covered both the case and mounting plate. I mounted 3 PG11 gland nuts for the cables. The box fit perfectly on the street side of the battery box. I ended up running the 4 gauge wires across the shunt because there wasn’t enough room to go straight with the cable lugs.

The new negative buss bar came with a protective cover which makes the installation look cleaner. I also too the opportunity to replace the factory positive blue ring terminal on the house feed because it felt loose which could increase resistance and eventually overheat. The parallel bridge cables were upgrade to 2 gauge.

With everything buttoned up I went in the trailer and connected to the BMV via Bluetooth. The app prompted me to update the firmware which completed in a few minutes. I now have a functioning Battery Monitor and the satisfaction of doing it myself!

[GMFL]

Looks good!

[jeffmc306]

Thanks Ronnie! I’ve learned a lot from your work, most recently on the Long Long Honeymoon Solar Project. Congratulations, that was huge and amazing work. Hats off to you!

[GMFL]

Originally Posted by jeffmc306

Thanks Ronnie! I’ve learned a lot from your work, most recently on the Long Long Honeymoon Solar Project. Congratulations, that was huge and amazing work. Hats off to you!

Maybe it will produces some more installs!

[bolerama]

That walnut stand is so beautiful! Great idea.

[Soready]

Can you provide the dimensions of the waterproof box or a link?

[jeffmc306]

Soready, sure thing!

I found this one at Amazon:
https://www.amazon.com/LeMotech-Junc.../dp/B07G4VT33F

I wasn’t sure what size gland nuts I would need so ordered this assortment:
https://www.amazon.com/KINYOOO-Water.../dp/B07C67XH1Z

Out of that kit I used three PG11’s; they fit the 4 gauge wire perfectly and I was able to fit the RJ12 communication cable end through one with some effort.

[Soready]

Thank you very much. I was able to route the data cable up through the entry like you. I have it fished up to the galley wall, still need to pull it up to the existing placement of the factory MPPT gage. Last piece of the puzzle was shunt placement and you solved that!!!!

[jeffmc306]

Originally Posted by Soready

Thank you very much. I was able to route the data cable up through the entry like you. I have it fished up to the galley wall, still need to pull it up to the existing placement of the factory MPPT gage. Last piece of the puzzle was shunt placement and you solved that!!!!

That’s great Rick! I might go through the extra step to fish it the rest of the way someday.

Here’s the negative buss bar I used in case you’re interested:
https://www.amazon.com/Bay-Marine-Su.../dp/B084H2JVQ6

[jeffmc306]

Today I finished the BMV-712 project by installing a Blue Sea 4-way disconnect switch. I chose the 4-way because it has three studs making it easier to connect the inverter and house supply cables.

I made a mounting bracket out of 16 ga. steel and attached it to the battery box just above the batteries. I moved the 100A fuse to the switch and the house cable to the fuse just like it came from the factory.

I made a new positive cable from the far end battery post to the disconnect switch. Once I figured out the layout and mounting, it came together quickly.

[OutdoorIdaho]

This thread is one that I have been referencing while planning the BMV-712 install for my 19' Caravel. It looks like you connected the shunt power lug to the disconnect switch Position 1 terminal. Have you had any trouble with the battery monitor retaining settings and info when you take the switch to off? Congrats on retirement, too, was Friday the big day?

[jeffmc306]

Originally Posted by OutdoorIdaho

This thread is one that I have been referencing while planning the BMV-712 install for my 19' Caravel. It looks like you connected the shunt power lug to the disconnect switch Position 1 terminal. Have you had any trouble with the battery monitor retaining settings and info when you take the switch to off? Congrats on retirement, too, was Friday the big day?

OutdoorIdaho, yes, Friday was my last day “in the office” (working from home)! It’s taking some getting used to but I’ll tough it out

Good eye about noticing the positive lead for the shut connected to the switch. We have factory solar so I leave the switch on all the time now to keep the batteries topped off. I guess I could move that lead back to the battery so the shunt/meter are live all the time.

I wonder if the meter has any flash storage to retain history. Maybe GMFL or some of the other solar guys would know.

Congratulations on the new Caravel! How do you like it so far?

Thanks for mentioning my retirement!
-Jeff

[OutdoorIdaho]

The Caravel is great and we are pleased with the floor plan and size.

I suspect there is flash memory in the monitor display but was not sure what all it retains. Though I suppose if it needs reset after winter storage that would not be a big deal.

Sadly, delivery times are getting long with everything going on so it looks like it could be May before I have all the parts for my install. That just gives me more time to think it through.

Thanks again for this write-up, it has been helpful in planning things out.

Cheers,
Nick

[jeffmc306]

Since the original BMV-712 installation I also replaced the factory Atkinson Solar Controller with a Victron MPPT 100/30 and took the old Atkinson CAT5 cable and used it to feed the BMV-712's display in the lounge area. I made a new Walnut wall plate.

[Hans627]

Originally Posted by jeffmc306

Since the original BMV-712 installation I also replaced the factory Atkinson Solar Controller with a Victron MPPT 100/30 and took the old Atkinson CAT5 cable and used it to feed the BMV-712's display in the lounge area. I made a new Walnut wall plate.

Jeff,

Well done, like everything you do!

[Life is a Highway]

Originally Posted by GMFL

Maybe it will produces some more installs!

Why am I crying l. I snoozed and forever sorry about that one

We lost the install but you do great work and are booked millions of years in advance now I guess