23fd Battery disconnect switch install

[Bobbo]

Will work fine. Personally, I don't like that much uninsulated copper attached to the hot terminal, and don't think disconnects should be on the ground terminal.

I only wanted to add disconnects to the propane detector and the inverter on mine. Other than those, I was happy with the factory installed disconnect. I moved the hot wire for the propane detector to the fuse block so the factory disconnector now turns it off. I added a Blue Sea disconnect to the hot wire going to the inverter.

[gypsydad]

So, are you saying you do not like all the connections going to one "disconnect" terminal? I was thinking of getting a second "Knife" style switch and spreading out the wires, as it is now connected. Do you think 2 switches is overkill? Wondering about the load if I put them all on a single Knife switch; comments welcome.

[Bobbo]

Originally Posted by gypsydad

So, are you saying you do not like all the connections going to one "disconnect" terminal?

If this question is directed at me, not at all. I don't mind everything being on one disconnect switch, if that is what serves your purpose. My purpose was to turn off the power to the inverter, while leaving everything else powered, like when it is at the dealer for warranty work. The inverter pulls a significant amount of current, even when "off." With 2 switches, I can completely power off the inverter and let it sit at the dealer. Or, I can power everything off. My personal preference is:

1. Things ALWAYS hooked to the battery (no disconnect):

Charge wire from tow vehicle
Charge wire from solar panels
Breakaway brake switch
Electric tongue jack

2. Things on a switch I can kill selectively:

Inverter

3. Things on a switch I can kill if called for:

Everything else (including propane detector)

Originally Posted by gypsydad

I was thinking of getting a second "Knife" style switch and spreading out the wires, as it is now connected. Do you think 2 switches is overkill?

Two switches is not overkill if you want to have different things unpowered at various times, but is unnecessary if you are going to power or unpower everything at once, always.

Originally Posted by gypsydad

Wondering about the load if I put them all on a single Knife switch; comments welcome.

As long as the switch is rated for all of the power draw, a single switch is fine. My inverter is fused at 110 amps. I don't know what the fuse is on the main power line, but the wire is smaller, so it would be fused smaller. As long as the switch is rated that high or higher, a single switch is fine. Note in my previous post that the Blue Sea Switch I installed is rated for 500 amps peak, 300 amps continuous. That is AMPLE for everything in my trailer.

[Burnside Bob]

Idea for mounting disconnect switch that won't get in way of upgrading to batteries bigger than group 24:



This was installed by/for the previous owner of my trailer. The switch is secured with 4 self tapping screws. The two screws that could theoretically touch a battery case were cut flush to the inside of the battery box with diagonal pliers.

The switch is wired on the positive side and when "off" isolates the batteries from everything except the tongue jack.

I don't have an inverter so have kept the #6 AWG wiring intact. A big "Thanks" to those contributors pointing out that #6 is inadequate for inverter duty.

[Mollysdad]

Originally Posted by Burnside Bob

Idea for mounting disconnect switch that won't get in way of upgrading to batteries bigger than group 24:



This was installed by/for the previous owner of my trailer. The switch is secured with 4 self tapping screws. The two screws that could theoretically touch a battery case were cut flush to the inside of the battery box with diagonal pliers.

The switch is wired on the positive side and when "off" isolates the batteries from everything except the tongue jack.

My battery box looks similar. How has the switch held up in the rain or wet driving? I'm looking into installing mine inside the battery box, but yours looks much simpler. Have you ever removed the knob? I understand it comes off by going to "off" then a little more.

As far as the knife switch, I understand they should only be used on the negative terminal, because all that exposed metal is asking for an accidental short. The battery posts are a different size between + and - so that will determine the placing.

[Burnside Bob]

Originally Posted by Mollysdad

How has the switch held up in the rain or wet driving? I'm looking into installing mine inside the battery box, but yours looks much simpler. Have you ever removed the knob? I understand it comes off by going to "off" then a little more.

No issues with the wet. I have not tried removing the knob. The battery box is somewhat protected by the propane tank shroud.

We keep our trailer in our driveway on shore power, but with the switch isolating the batteries. The batteries will very slowly drop OC voltage over several weeks and when I think its "time" I'll change to "house" for an overnight charge from the stock single stage converter--bout once a month. Then its back to isolation mode. I switch to "house" the night before we leave on a trip as the converter will charge the battery bank to a higher OC voltage than the TV.

[chaseav]

Originally Posted by Bobbo

My purpose was to turn off the power to the inverter, while leaving everything else powered, like when it is at the dealer for warranty work. The inverter pulls a significant amount of current, even when "off." With 2 switches, I can completely power off the inverter and let it sit at the dealer. Or, I can power everything off.

What are your thoughts on using the pictured battery selector switch to accomplish that isolation? I purchased a "dual battery cutoff switch" thinking it was this one so that I could isolate the inverter or use both but my $65 switch didn't afford that luxury and rather than deal with returning I just installed it. It works great, I just wish I had an isolate function and it drives my (surprisingly) nuts not having that big red knob affixed to something.

[chaseav]

* By the way, three years in and I think I've used the inverter twice. One of these days I'm going to buy a coffee maker under 1000 watts so I can actually use the inverter for what I'd intended... coffee while on the road.

[Bobbo]

Originally Posted by chaseav

What are your thoughts on using the pictured battery selector switch to accomplish that isolation? I purchased a "dual battery cutoff switch" thinking it was this one so that I could isolate the inverter or use both but my $65 switch didn't afford that luxury and rather than deal with returning I just installed it. It works great, I just wish I had an isolate function and it drives my (surprisingly) nuts not having that big red knob affixed to something. Attachment 300020

I highly recommend that switch. It can disconnect both of your circuits, individually. Put the house wiring on "1" and the inverter on "2." Then, if you want the house on but the inverter off, you can put it on "1." If you want the house AND the inverter on you can put it on "1+2." Just be sure to use HEAVY wire to run from the battery to the switch as it will take the load of both circuits. I would recommend 1/0 wire.

[Mollysdad]

Originally Posted by chaseav

* By the way, three years in and I think I've used the inverter twice. One of these days I'm going to buy a coffee maker under 1000 watts so I can actually use the inverter for what I'd intended... coffee while on the road.

Don't feel bad. I had my MH for 10 years, and the buyer asked about the inverter. "I have an inverter?" Sure enough, in the power bay was a beautiful Xantrex inverter. ( I thought that was the battery charger)
I always had shore power or ran the generator.

Originally Posted by chaseav

What are your thoughts on using the pictured battery selector switch to accomplish that isolation? I purchased a "dual battery cutoff switch" thinking it was this one so that I could isolate the inverter or use both but my $65 switch didn't afford that luxury and rather than deal with returning I just installed it. It works great, I just wish I had an isolate function and it drives my (surprisingly) nuts not having that big red knob affixed to something. Attachment 300020

Here's my understanding. It's sort of inverted thinking from the Marine world. Your RV batteries are paralleled. Take a lead from either + terminal to the "Output" terminal of the switch. Then connect the "Bat 1" to the converter +, and the "Bat 2" to the inverter +. Now, with the switch in "off" they're both off, and with the switch in "Bat 1" the converter is on but the inverter is off. In "Both" they're both on.

Oops. Bobbo beat me to it.

[NoResults]

For those of you who want the battery switch as described by chaseau' check prices. I bought mine on ebay for $32.00 shipped.

Dave

[NoResults]

chaseav What brand of AGM battery did you find that would fit in the battery box of a 23FB?

Thanks Dave

[chaseav]

Originally Posted by NoResults

chaseav What brand of AGM battery did you find that would fit in the battery box of a 23FB?

Thanks Dave

I don't have AGM's. I have Group 24 Autocraft Lead Acids. They seem to be taller than the original Interstates and sucked up a lot of real estate in there. But the big red switch still fits sort of between and rearward of the batteries. (I also don't have a 23FB but a 25FB... boooo, hissss, I know.)

[Bobbo]

Originally Posted by NoResults

chaseav What brand of AGM battery did you find that would fit in the battery box of a 23FB?

Thanks Dave

I am not chaseav, but I have a 2017 FC 23FB and these batteries are group 24 AGM's from NAPA. You can see where I mounted the disconnect switch for my inverter. It is mounted on a piece of Lexan.

[chaseav]

Originally Posted by Bobbo

Just be sure to use HEAVY wire to run from the battery to the switch as it will take the load of both circuits. I would recommend 1/0 wire.

Yes, for sure. The wire from my switch to the positive side of the batteries plus the parallel wires between the two batteries have been upgraded to 1/0 gauge wire. Sounds "easy" to do but those wires are nowhere near as flexible as the old ones. It took quite a bit of force to make the precut 1ft lengths fit. Wish I could custom cut and crimp.

[NoResults]

Bobbo, Thanks, I was looking for a reasonable priced Group 24 AGM. NAPA does not list a group 24 AGM on their web site.

I too have installed my battery disconnect on a piece of Lexan.

[Bobbo]

Originally Posted by NoResults

Bobbo, Thanks, I was looking for a reasonable priced Group 24 AGM. NAPA does not list a group 24 AGM on their web site.

I too have installed my battery disconnect on a piece of Lexan.

It is a 9824M.

[Mollysdad]

My latest vision has a three pole switch from Blue Sea Systems mounted in a plastic electrical junction box.
1. The Blue Sea switch has a ring of 3 5/16" that's a standard hole saw size. Only the ring and knob will show.
2. The box can be mounted on the outside of the battery box but the cables will still enter through a large hole in the back.
3. I think this will have the greatest weatherproofing, and take virtually no room in the battery box.

I considered two smaller single On/Off switches, but I didn't want to force a 2 ga. jumper between the two.

[billrector]

Originally Posted by Mollysdad

My latest vision has a three pole switch from Blue Sea Systems mounted in a plastic electrical junction box.
1. The Blue Sea switch has a ring of 3 5/16" that's a standard hole saw size. Only the ring and knob will show.
2. The box can be mounted on the outside of the battery box but the cables will still enter through a large hole in the back.
3. I think this will have the greatest weatherproofing, and take virtually no room in the battery box.

I considered two smaller single On/Off switches, but I didn't want to force a 2 ga. jumper between the two.

Edited....where will you mount the junction box? Have you done this yet? Pictures?

[Mollysdad]

Originally Posted by billrector

Edited....where will you mount the junction box? Have you done this yet? Pictures?

Not yet. I spend a lot of time thinking things through. I plan to mount it on the side of the battery box. The picture is not my battery box but mine is the same. See where the large cable exits? Right next to that. I'm hoping the cable for the existing converter and inverter will simply make a u-turn and enter my enclosure through a new hole in the battery box. I'll buy a #2 short red cable to go from the battery + to the switch. I'll need to cut the red cable with the post terminal (cover) off and crimp on a ring terminal. The only factor inside the battery box will be the screws holding the plastic box on and the cables winding around the batteries.

I think there'll be room between the battery box and the frame to reach the switch, and the box will receive some protection from the elements by the frame and propane tanks.

Of course, as they say, "The best plan changes when the first shot is fired."

I'll think this through, listen to all the others, then collect the parts and go for it. (I seem to do things the hard way, in the words of Mick Jagger, "Anything worth doing is worth overdoing.")