spoma
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Post by spoma on Feb 3, 2016 14:05:05 GMT -8
So, I know there are a million and one electrical posts on this site as well as around the web. I have read through quite a few of them and I just want to make sure I am understanding everything correctly. I do appreciate the help that everyone on this thread offers.
I have a newly acquired 1969 17' Shasta Starflyte. It is requiring a complete rebuild and all of the wiring needs to be ripped out and redone. I will put in a converter box and all lights on 12V. I will also have a 110 system which will run microwave, refrigerator, tv, air conditioner (summer), heater (winter), and the converter.
From what I am reading the "norm" seems to be to install a 30 Amp circuit ( (2) 15 Amp breakers) without a main breaker in the trailer. One of the 15 Amp breakers goes to the converter and the other goes to outlets to power everything. This seems under powered if you were using the microwave on a day where the air conditioner was running. I do see some that suggest running a completely new line for air conditioner and keeping it separate from the trailer 110 system.
I could put a box that has a main breaker (30 Amp) in it and this would allow me to separate it out onto more breakers, because the sum of the breakers could exceed 30 Amp, even though the sum of the load could not. I think this gives a little more flexibility from popping breakers where an air conditioner and microwave might exceed 15 Amp but likely wouldn't exceed 30 Amp.
Then there is always the option of putting in a 50 Amp service which would solve any power concerns in a small trailer. In reality it would be over kill but gives a lot more flexibility. It really wouldn't be extra work but does add some cost since everything is more expensive.
To some degree this is a personal preference, but I am interested to hear what people have encountered in working with 30 Amp service with the amenities I mentioned vs installing a 50 Amp service in a small trailer.
Thanks for any insight that can be offered.
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Post by vikx on Feb 3, 2016 23:10:26 GMT -8
A 30 amp inlet and wiring will run more than two 15 amp circuits. It will actually support 3 15s and one 20 if need be. Trick is to not use EVERYTHING at one time and be smart about the circuits. Note that to utilize 30 amps the trailer MUST be powered by a 30 amp outlet, no adapters.
Circuit 1, 15 amp: original basic lighting and a few outlets
Circuit 2, 20 amp: A/C
Circuit 3, 15 amp: Kitchen outlets, some lighting
Circuit 4 15 amp: extra outlets, converter
I recommend buying a basic house wiring book and studying/learning. It will help with designing the system and figuring out basic wiring techniques if you need it. (running wire, clamping, outlets, load, etc) It's important to understand what the entire trailer (30 amp) can power.
Most trailers do not have a main. They rely on the campground circuit breakers.
Another option for an A/C is a separate cord to the Campground outlet.
Hope this helps. It's hard to understand and chat about electrical.
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spoma
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Post by spoma on Feb 4, 2016 6:54:31 GMT -8
Thanks vikx. I am fairly familiar with home electrical, but just haven't worked in a trailer. I apologize that my question wasn't quite clear enough. I understand that a 30 Amp inlet can support more, but without a main breaker you shouldn't really add more than 30 amps worth of service unless you are completely relying on the campground breaker, which i don't love. But, you reply does give me the information i needed that it is the way that i should go.
i think i am going to add a 30 Amp main breaker (just for my own piece of mind) and then break it out similar to how you mention above. I am going to do all my lighting off 12V and have a converter. I will also do some 12V outlets (cigarette) and some 110. The problem I have is that we do about 75% of our camping with shore power, but we do enough without that i want to make sure it is comfortable.
thanks again for the feedback.
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Post by vikx on Feb 4, 2016 21:08:54 GMT -8
You're welcome.
Note: be sure to separate the grounds and neutrals in a trailer! It's a common occurrence with house wiring but in a trailer, all the white commons are isolated from the grounds/ground bar.
Just a head's up.
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spoma
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Post by spoma on Feb 5, 2016 10:10:03 GMT -8
Thanks for the heads up on the grounds and neutrals. I have been reading some about it already and I know especially with 12V the grounds/neutrals are extremely important and cause of most problems.
I am working on the details of my plan right now and once completed I will let you know my thoughts in case you see any holes in it.
thanks again.
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mobiltec
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Post by mobiltec on Feb 5, 2016 19:20:18 GMT -8
Just so you know. FYI...
The newer 50 amp trailers use a 220vac circuit just like your house and is split into two 110vac circuits independent of one another. One circuit is 30 amps and trickles down into 10 and 15 amp sub breakers. The other is a 20 amp circuit which also breaks down into smaller breakers. This type of circuit, just like your house wiring allows for twice the load on one line in. You'll notice on the 50 amp trailers and at the parks there is a 4 pin plug. That's the 50 amp 220vac plug. The three pin is the normal 30 amp 110vac line. The panel and power supply for the 50 amp circuit is going to be a bit more involved than the standard 110vac 30 amp system. But it allows for a lot more power usage too. With a 50 amp 220vac line coming in you CAN run just about everything at once.
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Post by vikx on Feb 5, 2016 21:32:32 GMT -8
Sounds like you are going to do fine.
Keep in mind that 12 volt has no neutral wires, just a ground and a hot.
110 has a black hot, white neutral and bare copper or green ground.
Take photos for us.
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spoma
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Post by spoma on Feb 17, 2016 11:43:30 GMT -8
vikx and mobiltec I want to thank you both for the informatino. I have done a bunch of research and decided I am going to go with a 30 amp circuit in the trailer. I am probably going to use one of the all - in - one devices out there which have AC / DC and converter all in one. This will save me a bunch of space in the trailer.
Thanks again.
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mel
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Post by mel on Feb 17, 2016 13:31:38 GMT -8
I hate that I dont understand all this wiring talk, it about the only thing on the forum that flies over my head. I think it is the part I dread most about the hole thing. Luckly I have a few months to get a better understanding of it and my husband is in school for electronics and my step dad knows a lot about it too... But I dont like relying on other people and Its something I would rather do myself so that I understand it.
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mobiltec
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Post by mobiltec on Feb 19, 2016 17:40:07 GMT -8
I hate that I dont understand all this wiring talk, it about the only thing on the forum that flies over my head. I think it is the part I dread most about the hole thing. Luckly I have a few months to get a better understanding of it and my husband is in school for electronics and my step dad knows a lot about it too... But I dont like relying on other people and Its something I would rather do myself so that I understand it. Well the problem with electrical and this is the reason I stay out of here most of the time is..... You have to understand it before you can do it yourself. If you want to understand the electrical go to Home Depot or Amazon and get a how to do basic house wiring manual. You need to know how electricity flows, where it goes, how to switch it, which side to switch, how to fuse, sizing of wire for different loads and all of that has to come out of a book or a class. If you don't know electrical, it can be the hardest part of the trailer to understand because you have to understand it before you can do it yourself. I'm not saying you can't understand it, you just need to read up on it first. Then come back here. Or hire an electrician for that part. |
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