30A Marinco inlet addition

[likeair2me]

I currently have the Scamp 110V cord that runs out through the mouse hole. I have no idea what gauge it is. I want to put a 30A Marinco twist lock inlet in it's place. I have (2)- 15A breakers in the box now. Would the cord that is currently in place be sufficient to cut and attach to the 30A Marinco inlet, or will I be needing some heavier gauge wiring for the wire from the box to the inlet?

Discuss.

[John in Michigan]

Behind the30amp Marino inlet you will need 30 amp capable wire running to a 30amp main breaker

[likeair2me]

So are you saying I need to swap the existing box for something with a 30A breaker? (current setup is two 15A breakers. No 12v applications at this time)

Would that be a 30A main, with additional breakers for individual services? (Window 5000 btu A/C to be installed and already have dorm fridge in place, interior outlets and a future curbside exterior outlet)

What gauge wire would need to be run from the inlet to the box? (What is the existing wire gauge, in case I want to salvage it for something else?)

[John in Michigan]

Yes, you will need a 30amp rated distribution box unless your existing distribution box is 30amp rated. It appears 10 gauge copper wire is needed between the Marinco inlet and the distribution box.

[John in Michigan]

If your camper power cord has standard 15 amp plug, the wire could be 12 or 14 gauge. To check the wire gauge, you would have to check the bare wire where its attached in your camper, or disassemble the plug.

Edit: I have used a wire stripper to determine wire gauge.
Edit: But really the cord insulation and individual wire insulation should be labelled.

[likeair2me]

Thanks John, I appreciate your straightforward answer. And thank you for not telling me to go find an electrician. I just want to know what kind of items to be looking for.

[John in Michigan]

You are welcome. If you don't have 30 amp service and want to switch to it, the most important thing is that the 110vac box / distribution box that is connected to shore power must be 30 amp rated. Typically it will have a 30 amp main circuit breaker slot and several circuit breaker slots for individual circuits in the camper. Usually the circuit breakers are purchased separately.

[steve dunham]

A 30 amp trailer service cord is 10/3 and rated for hard usage and for wet locations.

[likeair2me]

Looks like a breaker box will be on the list too. This unit did not have a heater, A/C, or a 3 way fridge when it came from the factory. The PO added a dorm fridge, and I want to add A/C and have the juice to run a little heater for those chilly times. I am not looking to winter camp, but sometimes it does get nippy.

So, a 30A rated box with space for two 15A breakers goes on the wanted list, along with some 10ga to hook it up.

[likeair2me]

I have already acquired a 30A Marinco locking cord for my future upgrade, but it's useless until I get the rest of the electrical system capable of handling the loads.

[steve dunham]

Many circuit breaker panels / load centers are circuit limiting .
The panel bus is designed so that the panel will only accept a certain number of circuit breakers. I would not install a 2 circuit load center if you plan on adding A/C . ( Your Picture)
A 4 circuit panel / load center is only a couple of dollars more and will allow you to install a 30 amp main breaker , your existing 2 circuits and put your A/C on a separate circuit.
Too small of a panel is only boxing yourself into a corner with no savings in labor or cost.

[likeair2me]

Steve, the box in the picture is the one already in there. I was just trying to find out if I needed a box with a 30A master breaker and then the two 15A breakers

[likeair2me]

The fridge says it pulls 1.35A and the A/C unit is 4.5A. My plan is to put the A/C in the bottom of the closet as Scamp did in the early installations.

The wiring setup as I bought it is one circuit going to an outlet on the left side of the kitchen cabinet base and nothing else on it, and the other side goes to an outlet box nailed to the floor, where the fridge and the right cabinet base outlet are plugged in. I believe some "modifications" happened in it's previous life.

[Casita Greg]

If you have a panel which has more than 2 breakers, a main breaker is required according to code. I would not recommend installing a 2 breaker panel if you are going to "upgrade" your electrical service in your trailer. As was previously mentioned above, if you have A/C, a heater, a fridge, etc, you will need more than the 2 breakers can provide. The heater and the A/C will need their own separate breakers as it is. If you also have a converter, that will also require its own breaker. If you don't have a converter, now would be a good time to think about installing one. It will give you a battery charger, 12 VDC fuse terminals, and several 120 VAC breaker spots. By the time you get done "Mickey Mousing" all this "Jerry rig" stuff you are looking at putting together, you'd be money ahead to just upgrade your whole power package to an all-inclusive converter, such as one of these load centers.

https://www.rvupgradestore.com/Paral...-p/19-1756.htm

And yes, all wiring, including branch circuits, that are rated to carry 30 Amp current must be a minimum of 10 gauge wire.

For my shore power retro mod I installed a Marinco 30 Amp Marine shore power outlet and adapted my cord, (which I cut off, but leaving enough of a tail inside to reach the new outlet,) then I installed a 30 Amp twist lock female end on the remaining cut off section of my shore power cord. Note, that if your internal wiring isn't 10 gauge, then it isn't rated to carry 30 Amps. Smaller branch circuits, (wiring downstream hooked up to their own breakers,) may be smaller based on the breaker capacity of the branch circuit. (15 Amp=14 gauge, 20 Amp=12 gauge, 30 Amp-10 gauge,) and should also be replaced as needed as a part of your upgrade.

[likeair2me]

As I said before, I HAVE the two breaker panel in the unit already. I am not looking to put one in. No Mousing attempts have been made beyond replacing a couple of broken side marker lights.

The plug in heater would only run when the Air Conditioner would not, and would not be a permanent installation.

[Casita Greg]

Whatever you want to do, but having only 2 breakers severely limits your ability to do much.

[stevebaz]

Unfortunately these old Scamps had minimum wiring to cover modern needs. My 1986 was the same way. Scamp needed power for the fridge and power on the cabinet. So they only put in the 2 breaker sub box and a 120 volt 15 amp power cord. The 12 volt DC side was the same a single fuse at the battery. No multiple fuse box and no battery charging capability and no converter to make 12 volt DC.

I ended up changing to Progressive Dynamics PD4045 to upgrade my power distribution.

Your problem with upgrading to a 30 amp cord and plugging into a 30 amp pedestal is you can now draw 30 amps down your original incoming power cord if you use reuse that cord between your breaker box and the new disconnect outlet. This gives you the potential to overload the wiring and possibly start a fire if you pulled full load on your 2 -15 amp breakers at the same time. At the minimum if you want to use the disconnect don't use a 30 amp plug at the pedestal use a 15 amp plug so you are properly protected by the pedestals 15 amp breaker.

This is the same problem people expose themselves to when they use a 30 amp to 15 amp plug adapter at the pedestal so they can plug in a 15 amp plug into a 30 amp outlet. If the trailer isn't wired direct through a 15 amp main breaker the individual breaker loads in the trailer added together can over load the cord. This is a problem in the early Scamps with divorced power systems.

[Johnny M]

I recommend you take a look at World Friendship Co. converters. They are very affordable and give you both AC and DC power for your unit. Mine was installed by the PO but has space for a 30 amp main and a few 15amp circuits. It also has a built in charger for your 12v batteries with (4) 12 volt fused circuits (used standard automotive fuses). Here is their link but you have to buy through their distributor network or their Amazon store:
wfcoelectronics.com | wfcoelectronics.com

[likeair2me]

So Johnny, is your panel the WF-8540? And do you find it to have sufficient power distribution without tripping the breakers on 110V uses?

[likeair2me]

Steve, So are you saying if I upgrade the incoming wiring from the inlet to the box to 10GA wiring, I will probably still trip the breakers?

No DC circuits are in the unit right now. No electric lights on 110v. Minimal electrical draws from the 1.35a fridge and the 4.5a air conditioner. Nothing else is planned to be wired in until I install a power center of some kind. It ain't nuthin but a hard top tent right now.