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Topic: 12V outlets, bus bar, and fusing. (Read 572 times) previous topic - next topic
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12V outlets, bus bar, and fusing.
So during the down time, I'm thinking it's time to run some 12V outlets around the rig. We only have one in the back where the TV cabinet is. The first thing I'm thinking is put a small hole in the wall behind the drivers seat closest to the outside. Then run wires straight up and make a little box to house one or two 12V outlets, plus a few USB outlets. Maybe do the same thing on the passengers side provided I can find a good way to get wires over there.

I was thinking of putting some type of 12V bus in the space behind the cabinet under the frig. Once you pull that draw out, you have pretty good access, and if I recall correctly, there is a bunch of open spaces. I figure it'd be pretty easy to run heavy duty wire through the battery box here to some sort of bus. Then I can do some home run runs from there to where I figure we need them. I have a few small inverters that I've used for powering laptops. I tried a long 12V extension, but it couldn't provide enough juice to keep the inverting running, so I want to use the highest amp outlets I can find.

I'm thinking a 12V fuse / circuit breaker between the bus bar and the battery (amps to be determined) and then smaller fuse at the end of each run right before the outlets.

I'd be interesting in anyone's thoughts and recommendations on gear.

Thanks in advance.

Sean
2001 MB
Re: 12V outlets, bus bar, and fusing.
Reply #1 –
Not sure what your needs are. How many amps do you want on DC? You can run, with some difficulty, larger gauge wire from the battery to most places. I have never needed more amps than the factory wiring provided, so I just tapped into existing DC wiring. You will find DC wires in all? of the overhead bins. Just remove the fourty thousand staples and you will them in a raceway below the shelf floor.

We needed AC and DC in the rear of our MB. So I put an inverter behind the driver's seat, which is close to the battery on an MB. Then I ran AC to the rear. I hope this will explain the method to you.

There are other ways to kill the cat, but this has worked for us.
Don & Dorothy
Sold our LD in June of 2023

Our boring always non-PC travel blog
Traveling Dorothy
Re: 12V outlets, bus bar, and fusing.
Reply #2 –
Quote from: henness  - 
So during the down time, I'm thinking it's time to run some 12V outlets around the rig. We only have one in the back where the TV cabinet is. The first thing I'm thinking is put a small hole in the wall behind the drivers seat closest to the outside. Then run wires straight up and make a little box to house one or two 12V outlets, plus a few USB outlets. Maybe do the same thing on the passengers side provided I can find a good way to get wires over there.

I was thinking of putting some type of 12V bus in the space behind the cabinet under the frig. Once you pull that draw out, you have pretty good access, and if I recall correctly, there is a bunch of open spaces. I figure it'd be pretty easy to run heavy duty wire through the battery box here to some sort of bus. Then I can do some home run runs from there to where I figure we need them. I have a few small inverters that I've used for powering laptops. I tried a long 12V extension, but it couldn't provide enough juice to keep the inverting running, so I want to use the highest amp outlets I can find.

I'm thinking a 12V fuse / circuit breaker between the bus bar and the battery (amps to be determined) and then smaller fuse at the end of each run right before the outlets.

I'd be interesting in anyone's thoughts and recommendations on gear.

Thanks in advance.

Sean

You could use this or similar.
Blue Sea 5029 ST Blade Fuse Block w/Cover - 12 Circuit w/outNegative Bus |...
Or something cheaper
6/12 Ways Fuse Box 12V/24V Bus Bar Car Marine Fuse Box Holder with LED...

Running 12-volt wires from the battery area to the rear is difficult in a MB, it's hard to get around the bathroom and might be easier to go through the floor and run the wires under the rig, coming back up through an exterior cargo bin.
Wiring can exit the cab through a hole under the cab's plastic step cover, shown below.
LD wiring | Flickr

How big an inverter are you planning on running.  A large inverter should be mounted close to the battery box to keep the wire size reasonable and voltage drop low.

As Don mentioned, the existing wiring may have unused capacity and it's available for small devices, such as more LEDs or USB chargers. The overhead cabinets are a good source of excess power, especially if the rig was originally wired for incandescent lights that have been changed to LEDs.
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: 12V outlets, bus bar, and fusing.
Reply #3 –
So can someone with an early 2000 MidBath help me remember.... There is a raceway behind the toilet for wiring that can route wire from the power distribution center to under the shower.  I seem to remember that there is a hollow wall next to the shower that ran wires up to where the tube TV was installed. That odd shaped angled space. Question:  isn't there a place to separate a wire bundle and run it in the storage compartment (below the slide-out bed platform) from inside that wall?   Might be 'fiddley' to fish the wires.   That area back behind the toilet was so bad I used gloves, and completely remade that cover to be easier to remove, easier to clean, and polypro on the top.
    Second question:  was there an access panel for the trap on the shower, or was that access from below, under the floor?
    The back wall of the midbath could have 110 VAC outlets, and very shallow 12 VDC sockets in the wall. It might be possible to run wiring over to the passenger side through the back wall. There is also a channel under the floor for cold water going from pump to water heater, and back to sinks and shower hot water.  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: 12V outlets, bus bar, and fusing.
Reply #4 –

Sean,

Why are you running completely new wires for 12V?  Likely you are using low wattage items (e.g. we have led lights, electronics charging, etc. and it just doesn’t add up to many watts even if we use them all at the same time – which we don’t).  If you have not yet switched over to LED lighting, that could make a difference but you could easily replace with led bulbs (lots of posts in the forum on that).

We just looked for the closest DC12 fixture (light, fan, etc.) that was close to where we wanted the new outlets.  Then ran wire from that fixture to the new spot and put in a new DC12 outlet.  Be aware if a switch controls the fixture you are taking the electricity off, as at least for our front LD lights the switch would also control the new outlet. 
I see Don did the same (Don, your LD was put together very well, we only had 25 thousand staples  :D ).

The 3 outlet horizontal devices we put in are no longer sold by Amazon  but it is very similar to 
these horizontal 3 outlet devices
We have been very happy with them.   I think Andy first told us about horizontal 12V outlets and ours have been pretty tight with little movement over time.

We added these to create usb outlets at some of the spots.  USB adapter and again they feel well made and we have been happy with them.

Also, we have used a very long Heavy Duty 12V extension cord with no problems…. Having used it in a couple 12v outlets for various reasons.  But it does say Heavy Duty...

Just to share (while I am mucking in our old Amazon orders), we recently got this vacuum and have been much happier with it than the stick vacuum we used previously.  And it is a DC12 vacuum which is a nice plus.  Not the strongest vacuum - it won’t hold up a bowling ball, but good for what we need it for and it has a hose attachment to get under the cab seats, etc. which is nice.


As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Jane & Scott
Currently have a 1989 TK  LD we did a lot of upgrades on.
Bigfoot 25RQ Twin on order with early summer 2024 ETA

Our smartphone autocorrects into very poor English.
 We disclaim the illusion of ignorance this creates as we have enough ignorance we rightly claim.
Re: 12V outlets, bus bar, and fusing.
Reply #5 –
Quote from: Jane and Scott  - 
Sean,

Why are you running completely new wires for 12V?  Likely you are using low wattage items (e.g. we have led lights, electronics charging, etc. and it just doesn’t add up to many watts even if we use them all at the same time – which we don’t).  If you have not yet switched over to LED lighting, that could make a difference but you could easily replace with led bulbs (lots of posts in the forum on that).

We just looked for the closest DC12 fixture (light, fan, etc.) that was close to where we wanted the new outlets.  Then ran wire from that fixture to the new spot and put in a new DC12 outlet.  Be aware if a switch controls the fixture you are taking the electricity off, as at least for our front LD lights the switch would also control the new outlet. 
I see Don did the same (Don, your LD was put together very well, we only had 25 thousand staples  :D ).

The 3 outlet horizontal devices we put in are no longer sold by Amazon  but it is very similar to 
these horizontal 3 outlet devices
We have been very happy with them.   I think Andy first told us about horizontal 12V outlets and ours have been pretty tight with little movement over time.

We added these to create usb outlets at some of the spots.  USB adapter and again they feel well made and we have been happy with them.

Also, we have used a very long Heavy Duty 12V extension cord with no problems…. Having used it in a couple 12v outlets for various reasons.  But it does say Heavy Duty...

Just to share (while I am mucking in our old Amazon orders), we recently got this vacuum and have been much happier with it than the stick vacuum we used previously.  And it is a DC12 vacuum which is a nice plus.  Not the strongest vacuum - it won’t hold up a bowling ball, but good for what we need it for and it has a hose attachment to get under the cab seats, etc. which is nice.



One of the area's I want to run power to doesn't have any exiting wires near it. Bunk above the drivers seat.

The two small inverters I have are:

An APC PNoteAC75. It's 75W and draws 8A max on the 12V input.

A Peak PKC0M04. It's a 400W and it draws 38A max on the 12V input. But that is with hard wired run. The cig lighter adapter plug is 8A.

I want to be able to supply about 10A total at the end of each of the runs.  That would allow the kid to have her 60W laptop adapter plus iPad charger while she's up in the bunk off the house batteries.
As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
2001 MB
Re: 12V outlets, bus bar, and fusing.
Reply #6 –
Quote from: henness  - 
One of the area's I want to run power to doesn't have any exiting wires near it. Bunk above the drivers seat.
The two small inverters I have are:
An APC PNoteAC75. It's 75W and draws 8A max on the 12V input.
A Peak PKC0M04. It's a 400W and it draws 38A max on the 12V input. But that is with hard-wired run. The cig lighter adapter plug is 8A.

I want to be able to supply about 10A total at the end of each of the runs.  That would allow the kid to have her 60W laptop adapter plus iPad charger while she's up in the bunk off the house batteries.

Consider bringing 8-gauge wires directly from the battery box into the cabinet under the refrigerator, adding a 60-amp MaxiFuse and holder, and then continuing the run up the side of the refrigerator cabinet up to the bunk. The 400-watt inverter could be mounted on the side of the refrigerator.
For the rear of the coach, the existing wiring in the overhead cabinets should have adequate capacity to supply 8-amps for the  75-watt inverter. Replacing the Lounges's incandescent and florescent lights, in the overhead cabinets, with LEDs should free up the needed capacity.

Both Don and Ron claim there is a possible wire run through the bathroom, under the shower. If so, power can come directly from the Power Center.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: 12V outlets, bus bar, and fusing.
Reply #7 –
Hi Sean,  The bunk cabover bed has lighting, and the fantastic fan. The wiring size is adequate (14 or 12 Ga.) to run 8 amps extra for a PC charger. I can't remember what else is on that particular fuse.  But that wall at the cabover is hollow, and the new heavier duty wires from the power center can be run up under the sink, under the refrigerator and inside that wall to a dedicated outlet.   Is that original 400W (nearly) sine wave inverter still under the refrigerator?  That could be used in the cabover if it isn't being used anywhere else.  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: 12V outlets, bus bar, and fusing.
Reply #8 –
Quote from: RonB  - 
Hi Sean,  The bunk cabover bed has lighting, and the fantastic fan. The wiring size is adequate (14 or 12 Ga.) to run 8 amps extra for a PC charger. I can't remember what else is on that particular fuse.  But that wall at the cabover is hollow, and the new heavier duty wires from the power center can be run up under the sink, under the refrigerator and inside that wall to a dedicated outlet.   Is that original 400W (nearly) sine wave inverter still under the refrigerator?  That could be used in the cabover if it isn't being used anywhere else.  RonB

My bunk cabover doesn't have a fantastic fan. It only has two lights at the passenger side. The kid won't listen to reason and use that as the head of her bed ;) so that's why I want the outlets on the driver side.

The only inverter that came w/ my rig is the small APC one that they must have used to power the TV. The TV wasn't installed when we got the unit.

I bought a bigger pure sine inverter that I was planning on putting in the space under the fridge.
2001 MB
Re: 12V outlets, bus bar, and fusing.
Reply #9 –
Hi Sean.  It's good to keep in mind that inverters are only about 95% efficient.  About 5% of the power is wasted as heat, even when you aren't using it. Not a problem with small loads. A microwave is a whole different situation. You would benefit to turn it off when you aren't using it. Next to the battery box is a good place for it.  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB