Do I have to install a 12 volt fuse panel?

[knishiya]

Hi,

I have a 67 Caravel that i am doing a frame on redo. Right now, I am working on the electrical. I have a 70 y.o. master electrician doing the majority of the work.

It was completely gutted. New wiring. New panel. New Progressive Dynamics 9245 converter. two batteries on the tongue.

Question - He did not have a 12 volt fuse box/panel and is deciding to not put one in. Is this a bad idea? If one is not installed, what can happen or worse thing that can happen?

There is a fuse on the converter, i guess that protects it from surges, etc.

I dont have too many 12 volt circuts going. Mainly lights. An outlet, fantastic fan that has a fuse.

[68 TWind]

Every 12V circuit should have it's own fuse. 12 Volt DC RV panels with a several lines are not expensive and I would certainly install one. Now is the time. An arched 12V from a big 12v battery carries lots of amps and you don't want that to happen. The 68's had a "control panel" which is up front which is basically a fusebox for the 12V system. Each 12V circuit has it's own breaker. I think the 67's had fuses/breakers back near the battery area and you can go back like the original if you don't want to buy a new panel. I'm sure someone here can send pics if you need them.

[toastie]

Yes

See my post #601 and #602 http://www.airforums.com/forums/f36/...-38289-43.html

See post #416 http://www.airforums.com/forums/f36/...-38289-30.html

Attached diagram which calls for a fuse at 55 amps and no greater than 18" from the battery

toastie

[dlb435]

Yes, don't skimp on safety.

[Aage]

Having a fuse in each line of 12V current draw allows you to carry on with the good circuits should one line become shorted.

They also prevent excessive current draw, which could cause a fire.

No choice: you really need them on each line.

I've attached a photo of the one we liked and bought from Vintage Trailer Supply. Easy to use, and it has a door to protect all circuits.

[RickDavis]

If he doesn't think the 12 volt circuits need individual fuses or breakers you need an electrician that doesn't want to take dangerous short cuts.

[Inland RV Center, In]

Originally Posted by knishiya

Hi,

I have a 67 Caravel that i am doing a frame on redo. Right now, I am working on the electrical. I have a 70 y.o. master electrician doing the majority of the work.

It was completely gutted. New wiring. New panel. New Progressive Dynamics 9245 converter. two batteries on the tongue.

Question - He did not have a 12 volt fuse box/panel and is deciding to not put one in. Is this a bad idea? If one is not installed, what can happen or worse thing that can happen?

There is a fuse on the converter, i guess that protects it from surges, etc.

I dont have too many 12 volt circuts going. Mainly lights. An outlet, fantastic fan that has a fuse.

Fuse panels are absolutely necessary in any electrical circuit.

They prevent fires and deaths because of a fire.

Your friend needs to practice safety, period.

His "master technician" permit should be revolked, pronto, before his misguided advice causes a death.

Andy

[lewster]

I might as well pile on a little...............

According to RVIA standards and the NEC (hopefully, your 'master electrician' knows what those initials represent), every circuit, whether AC or DC, should have over-current protection on it to be sized according the the wire gauge being used.

That means an AC circuit breaker on every line entering the AC circuit breaker panel (hopefully you have on of these...) AND a DC fuse on every DC circuit.

Again, ampacity is determined by the wire gauge, as in 15 amps for 14AWG and 20 amps for 12AWG. You should also have a main DC fuse or circuit breaker located within 18" of the batteries sized to the cable leading to your DC fuse panel, as the purpose of a fuse or circuit breaker IS TO PROTECT THE WIRE

[Crusty]

If you only have a few 12v circuits, you might be able to get by with inline fuses in each circuit, though I consider them to be a bit on the troublesome side. I would at least look for marine fuse holders so that they're somewhat protected against moisture and they should be located as close as possible to the 12v source.

Electrical fires which start in the night when the RV occupants are asleep can kill.

[ronsgto]

Originally Posted by knishiya

Hi,

I have a 67 Caravel that i am doing a frame on redo. Right now, I am working on the electrical. I have a 70 y.o. master electrician doing the majority of the work.

It was completely gutted. New wiring. New panel. New Progressive Dynamics 9245 converter. two batteries on the tongue.

Question - He did not have a 12 volt fuse box/panel and is deciding to not put one in. Is this a bad idea? If one is not installed, what can happen or worse thing that can happen?

There is a fuse on the converter, i guess that protects it from surges, etc.

I dont have too many 12 volt circuts going. Mainly lights. An outlet, fantastic fan that has a fuse.

I know this is an old post but it would be nice to here from original poster as what was done. I am an auto tech and yes you must have a fuse panel or inline fuse to protect each circuit. The electrician would know this seems that there may be some confussion as to what he is planning. What did you end up doing? If installed which panel did you use. This info can be helpful others doing the same thing.

Ron L

[DriftingDrew]

Thread Revival! If I'm counting correctly, I have/will have over 25 DC circuits in the AS Excella 500, not including the 4 or 5 for the exterior trailer lights (running, reverse, etc.) which do not seem to have any original fuses. Am I reading correctly that I need a fuse for each of these circuits?? The original Univolt system only had about 8 fuses - and many of the same circuits (per the manual), so I'm wondering if several things can be combined (like power-sipping LEDs). If I can't combine them, what Power Center provides a DC fuse board that big (currently looking at this Boondocker 60 Amp which only has about 12 DC circuits).

Listed below are the DC circuits I'm counting - any additions or corrections would be appreciated!

1) 2 x Bed Lamps
2) Trunk Light (external access compartment)
3) 4 x Speakers
4) SeeLevel Tank Monitors
5) Bathroom Exhaust Fan
6) 2 x MaxxFan Deluxe
7) Composting Toilet Fan
8) 3 x 12V Outlets
9) 2 x Bathroom Lights (overhead & mirror)
10) Air Conditioner Thermostat
11) 2 x End Cap LED Strip Lights
12) Radio/Stereo/Bluetooth System
13) Livingroom/Kitchen Ceiling Lights
14) Bedroom Ceiling Lights
15) Water Heater Ignition
16) Furnace/Heater Ignition
17) Oven Light
18) Connection to Batteries (circuit breaker or fuse?)
19) Solar Hook-up (charge controller might serve as this fuse?)
20) Water Pump
21) Awning Lights
22) Porch Light
23) Cabinet/Drawer LED Lights
24) Closet LED Lights
25) Doorbell (this will probably be removed completely)

Thanks for any help!
Drew

[fran&frank]

Just like every AC fixture doesn't need its own circuit, either does every DC fixture. You need to figure out what you can combine based on its required amps and what makes since based on the path of your wire and then size the wire and fuse appropriately for each circuit.

[mythbuster88]

Originally Posted by lewster

I might as well pile on a little...............

According to RVIA standards and the NEC (hopefully, your 'master electrician' knows what those initials represent), every circuit, whether AC or DC, should have over-current protection on it to be sized according the the wire gauge being used.

That means an AC circuit breaker on every line entering the AC circuit breaker panel (hopefully you have on of these...) AND a DC fuse on every DC circuit.

Again, ampacity is determined by the wire gauge, as in 15 amps for 14AWG and 20 amps for 12AWG. You should also have a main DC fuse or circuit breaker located within 18" of the batteries sized to the cable leading to your DC fuse panel, as the purpose of a fuse or circuit breaker IS TO PROTECT THE WIRE

And I'll pile on too. My 2016 has a 6AWG wire going from the battery directly to a 12V bus in the front of the trailer. There is no DC fuse or circuit breaker. The electrical drawing shows a circuit breaker but AS did not see fit to put one in.

Bummer.

But you are correct and I will install one.

[mimiandrews]

Remember, the fuse is there to protect the wiring, not the electrical loads themselves. Combine the smaller loads on the same circuit where it makes sense. Give the big loads their own (adequately sized) wire and breaker.

[DriftingDrew]

Thank you for the responses! I'll see what I can combine - might use terminal blocks like SuzyHomeMakr suggested somewhere.

[Lumatic]

My 73 has 4 original 12vdc circuits for everything that runs off the house battery.
The running lights, brake stop and taillights, and brakes which are fused through the tow vehicle and it's starting battery.The breakaway switch and tongue jack also are powered by the house battery and have a fuse on the tongue.