Fusing question for main power cord

[Pat J]

Pat,

There are only two 15A circuit breakers, but those are on the converter output side so it doesn't get fried by a fault somewhere downstream. There is no circuit protection on the input side of the converter. I could stick with a 30A extension cord, add a circuit breaker, or accept the logic that we often use extension cords sized appropriately for the load that are lighter duty than the breaker they're connected through, as Pete reminded.

Parker

Parker,

What year is your Scamp? I've had two Scamps (1992 & 1994) and both came from the factory with protection for the 120V circuits. Based on your previous post you evidently have 120V running to the fridge, at least one outlet (for your cube heater), and to the power converter. I would be very uncomfortable relying on the shore power cord as the "fuse" in the event of a 120V short or circuit overload inside the camper. The vision of a Scamp going up in flames is not a pleasant one for me.

Pat

[Parker Buckley]

Parker,

What year is your Scamp? I've had two Scamps (1992 & 1994) and both came from the factory with protection for the 120V circuits. Based on your previous post you evidently have 120V running to the fridge, at least one outlet (for your cube heater), and to the power converter. I would be very uncomfortable relying on the shore power cord as the "fuse" in the event of a 120V short or circuit overload inside the camper. The vision of a Scamp going up in flames is not a pleasant one for me.

Pat

Pat,

It's a 2004 model. There is circuit protection for both 120V lines, which come out of the converter. I don't see any sort of fuse or circuit breaker on the power cord which runs from the backside of the converter to the pedestal, nor do I see why one one be necessary if everything is rated for 30A. That's the job of the breaker in the pedestal, at least from what I can tell. We can still discuss the wisdom of running a 15A cord from the converter to the pedestal, if it's connected to the 30A breaker there, rather than the 15A one that usually sits next to it. I'm still puzzling over how great an idea that is, but I think it's done quite often, othewise they wouldn't sell so many adapters to make it easy.

Parker

[Pat J]

Pat,

It's a 2004 model. There is circuit protection for both 120V lines, which come out of the converter. I don't see any sort of fuse or circuit breaker on the power cord which runs from the backside of the converter to the pedestal, nor do I see why one one be necessary if everything is rated for 30A. That's the job of the breaker in the pedestal, at least from what I can tell. We can still discuss the wisdom of running a 15A cord from the converter to the pedestal, if it's connected to the 30A breaker there, rather than the 15A one that usually sits next to it. I'm still puzzling over how great an idea that is, but I think it's done quite often, othewise they wouldn't sell so many adapters to make it easy.

Parker

OK, now I think I understand. The newer Scamps, like yours, have the 120V breakers in the same unit as the power converter; the older ones, like mine, have a 120V breaker box that is separate (and upstream, electrically speaking) from the power converter. The two 15A breakers you describe are what protect your 30A shore power cord (even if it is connected to a 50A campground pedestal).

Pat

[Pete Dumbleton]

Breakers are intended to protect *wiring* downstream, not upstream. The breakers inside the Scamp, be they in the converter (later models) or in a separate box (earlier models) are there to protect the Scamp's internal wiring, not the shore cable.

There is no dedicated protection for the shore cable, anymore than there is for your home appliances, like a toaster, lamp, TV set, water heater, dryer, etc., or for the wires feeding them.

The pedestal sees your Egg as an appliance, that just happens to have some internal protection for its internal wiring but not for its plug and cord.

BTW, electrically, it doesn't matter if the circuit breakers are inside the converter or outside, they are wired so the shore cable goes to the breaker(s) before the converter.

[Parker Buckley]

Okay, the deed is done. I pulled out the 30 amp cable and installed a Marinco battery charging outlet as mentioned in an earlier post. This was really easy to do by making up a plywood flange to mate with the original holes in the Scamp. I'm now set up for a 15 amp extension cord arrangement. I also installed a bulkhead under the bench so we can use that area for storage without worrying about blocking the cooling air behind the converter. None of this is permanent or costly, so if at some point I feel like I need to return to 30 amp service, it will be easy to do. The pictures show the external outlet and the installation under the seat, including the new bulkhead. I took these pictures with 120V lighting plugged into the Scamp system. Please note the absence of smoke.

Thanks everyone for all your suggestions.

Parker

[Ed Harris]

Nice and you didn't let the smoke out either!