378MBS-R Victron & BattleBorn install

[Jeffsav]

Took delivery of our 2022 378MBS-R at the end of February and started on the upgrades. Wanted to install two BattleBorn GC3 batteries and full Victron system without taking up any storage space as we full time and I knew GD often hide usable space. Unscrewed the wall panel in the passthrough area to find what I have to work with. Lots of space in there once I did some GD cable management, added a 2x2 frame and 1/2 ply backing panel on the rear of the outdoor kitchen wall that would be used to mount the Victron gear, and built a new small wall at the rear of the new space. Then moved the central vacuum back and 120V outlet into the new wall. Had GD send me some storage bay felt to finish new panels off same as the rest of the storage bay. Kept the old converter just in case it’s ever needed in the future and mounted it out of the way.

Spent quite a while fishing a pull cord from the storage bay, under the midbunk floor and up inside the kitchen wall to the control panel area. I was then able to pull wires in either direction for Surge Guard remote, SeeLevel display, and Touch50 display. Installed a USB in there too.

I wired the solar breaker box, solar chargers, Lynx Distributor, SmartShunt, BlueSea class T fuse & cutoff switches, Cerbo GX and Multiplus II onto the backing panel outside on the work bench. Was able to hide most cabling behind the panel so it’s a pretty clean install. The 4/0 cable are the only ones not hidden. Was able to manoeuvre the panel and gear into the storage bay and screwed it all into place.

FYI - the “roof satellite access channel hole” is nowhere near the interior of the wall that the cable is supposed to go into, it’s probably 12” away. Thanks Grand Design, if you are giving us a roof access channel, the top and bottom holes and pull string need actually be lined up!!!!! So I resealed the small GD hole panel back up and after some research decided to drill a new 2” hole next to the tanks vent stack and mount my roof access box there. 2 pairs of 10 gauge solar cable came down easily exactly where I expected them to be near the water heater.

So far the system is running really well. Have tested solar, AC and DC systems and happy with the results. SoftStart coming this week which will get wired into the bedroom AC and a ducted 12v fan system is going to get installed by the batteries and inverter to provide airflow while boondocking.

I really wanted to share my experiences with everyone who is thinking of tackling such a project but worried that they will loose storage space or have to add weight to the front bay. I was able to use 100% otherwise hidden wasted space, and also move the weight of batteries and Victron gear back nearer the axles. Both of which were my 2 main goals where the system was located.

[Soundsailor]

Took delivery of our 2022 378MBS-R at the end of February and started on the upgrades. Wanted to install two BattleBorn GC3 batteries and full Victron system without taking up any storage space as we full time and I knew GD often hide usable space. Unscrewed the wall panel in the passthrough area to find what I have to work with. Lots of space in there once I did some GD cable management, added a 2x2 frame and 1/2 ply backing panel on the rear of the outdoor kitchen wall that would be used to mount the Victron gear, and built a new small wall at the rear of the new space. Then moved the central vacuum back and 120V outlet into the new wall. Had GD send me some storage bay felt to finish new panels off same as the rest of the storage bay. Kept the old converter just in case it’s ever needed in the future and mounted it out of the way.

Spent quite a while fishing a pull cord from the storage bay, under the midbunk floor and up inside the kitchen wall to the control panel area. I was then able to pull wires in either direction for Surge Guard remote, SeeLevel display, and Touch50 display. Installed a USB in there too.

I wired the solar breaker box, solar chargers, Lynx Distributor, SmartShunt, BlueSea class T fuse & cutoff switches, Cerbo GX and Multiplus II onto the backing panel outside on the work bench. Was able to hide most cabling behind the panel so it’s a pretty clean install. The 4/0 cable are the only ones not hidden. Was able to manoeuvre the panel and gear into the storage bay and screwed it all into place.

FYI - the “roof satellite access channel hole” is nowhere near the interior of the wall that the cable is supposed to go into, it’s probably 12” away. Thanks Grand Design, if you are giving us a roof access channel, the top and bottom holes and pull string need actually be lined up!!!!! So I resealed the small GD hole panel back up and after some research decided to drill a new 2” hole next to the tanks vent stack and mount my roof access box there. 2 pairs of 10 gauge solar cable came down easily exactly where I expected them to be near the water heater.

So far the system is running really well. Have tested solar, AC and DC systems and happy with the results. SoftStart coming this week which will get wired into the bedroom AC and a ducted 12v fan system is going to get installed by the batteries and inverter to provide airflow while boondocking.

I really wanted to share my experiences with everyone who is thinking of tackling such a project but worried that they will loose storage space or have to add weight to the front bay. I was able to use 100% otherwise hidden wasted space, and also move the weight of batteries and Victron gear back nearer the axles. Both of which were my 2 main goals where the system was located.

Beautifully done install.

[Ynot4me2]

Beautiful and impressive setup. Congrats. Nice clean job

Sent from my SM-P610 using Tapatalk

[brandtb1919]

Nicely done! I agree that GD leaves a lot of useable space behind the basement walls. I was also able to get my entire system in place without losing any storage area.

Brian

[zhazell]

That looks awesome and clean. Great job!

I have a 377MBS, the older model with the loft above the mid-bunk. I was trying to figure out a way to pull wire/pull string for my Surge Guard into the control area cabinet, but it's so tight under/behind the breaker panel I wasn't able to find a way to fish the wire. How were you able to get the wires needed up there?

[traveldawg]

Wow! Impressive installation. Very nice.

What caught my eye was the Garmin inReach (nice choice) and now I want to make my storage wall so it slides.

Thanks for the photos.

[Jeffsav]

I pulled the vacuum sweep door under my kitchen cabinet out of the way and was able to run a string down from behind my control panel through the wall to the tight title gap where the vacuum sweep door is. The factory wires to the control panel come up through the floor behind the vacuum sweep door and go under the mid bunk floor across to the back of the fuse panel. I have pull strings all the way from behind control panel to the storage bay where the equipment is. It’s a 2 man job to pull wires all that way as there’s a few obstacles but I managed ok. I wish GD put large holes for additional cables as things are pretty tight under the cabinet and a pull string would be so helpful when installing all the things that should be standard on their top flight Solitude line.

[brandtb1919]

That looks awesome and clean. Great job!

I have a 377MBS, the older model with the loft above the mid-bunk. I was trying to figure out a way to pull wire/pull string for my Surge Guard into the control area cabinet, but it's so tight under/behind the breaker panel I wasn't able to find a way to fish the wire. How were you able to get the wires needed up there?

It varies on the model, but sometimes the best way is to cut an additional access hole. On my 310, there is a large hole behind the breaker panel from the factory that goes to the basement area. However, trying to fish a wire from the control panel area down through this was impossible with how stuffed it was. I have a drawer above the breaker panel that works nicely to conceal an additional hole I cut so I wasn't trying to fish wires the entire way. It is still tight, but now takes 10min instead of an hour.

Factory hole:



New hole:



I cut it very carefully with a utility knife.

Brian

[zhazell]

I pulled the vacuum sweep door under my kitchen cabinet out of the way and was able to run a string down from behind my control panel through the wall to the tight title gap where the vacuum sweep door is. The factory wires to the control panel come up through the floor behind the vacuum sweep door and go under the mid bunk floor across to the back of the fuse panel. I have pull strings all the way from behind control panel to the storage bay where the equipment is. It’s a 2 man job to pull wires all that way as there’s a few obstacles but I managed ok. I wish GD put large holes for additional cables as things are pretty tight under the cabinet and a pull string would be so helpful when installing all the things that should be standard on their top flight Solitude line.

Thanks Jeff. I pulled my breaker panel out and there is a nice hole in the wall with the wires going up to the control panel. Not worried about that as that's an easy run. I was having a hard time with getting a pull string (or using the existing coax cable) through the hole in the floor where all the cables go. It's very tight and nothing was wiggling or moving. When I have a second person to help out, I'll try again. I'll get it, just going to have to be patient. Once I get a pull string through, hopefully additional runs are easier as I want to get both my battery monitor and surge guard displays mounted in the hutch.

It varies on the model, but sometimes the best way is to cut an additional access hole. On my 310, there is a large hole behind the breaker panel from the factory that goes to the basement area. However, trying to fish a wire from the control panel area down through this was impossible with how stuffed it was. I have a drawer above the breaker panel that works nicely to conceal an additional hole I cut so I wasn't trying to fish wires the entire way. It is still tight, but now takes 10min instead of an hour.

Factory hole:



New hole:



I cut it very carefully with a utility knife.

Brian

Thanks for the insight! I'll try again when I have the time and help. It's very tight and would be nice if Grand Design included a pull string with all those wires and maybe made the hole a little bigger lol

[jm_bc_]

Beautifully done installation my friend!