Trailer Sub-panel wiring and grounding?

[odSteve]

Hi, newbie here seeking advice.
I have a semi-truck box trailer I'm converting into a workshop. Wheels and suspension have been removed and it’s sitting on railroad ties on the ground. Because it’s not on a permanent foundation I'm not allowed to permanently wire it to the house.
I have chosen a 100 amp Square-D loadcenter breaker panel box for inside the trailer (the store's recommendation). And I've chosen a marine type of plug and socket to connect to the trailer with.

ParkPower Catalog - http://www.delzer.com/powerproducts/parkpowerfullline/18/#zoom=z
and
ParkPower Catalog - http://www.delzer.com/powerproducts/parkpowerfullline/14/#zoom=z

Scroll down on those link pages to see the 50 amp connection hardware I’m considering. My thinking is if it’s good enough to seal out ocean water, it should be good enough to seal against rain and snow.
My first of several questions:
Q1 - Do you agree with my choice of indoor loadcenter breaker box and outdoor trailer input power connection hardware?
I’ve never worked as an electrician – I’m just a self-taught DIY. I have a fair understanding of the theory of electricity but not the hardware to control it.
So my next question is should I only run three wires from the house (two hots and neutral) to the input of the trailer and just earth ground everything separately in the trailer (switches, panel, plugs, conduits, etc) to a couple earth ground rods? At my house the common neutrals and grounds are all tied together but I think it would be better to keep the common/neutral circuit separate from the earth ground connections in the trailer.
Q2 - Do you agree?
Q3 - Finally what size and type of wire do you recommend I run from a 240volt plug at my house to the input of the trailer?

It’s about a 120 ft outdoor run. The loadcenter panel box has a 100 amp master breaker in it. And my trailer is all aluminum (including the frame). The wall construction consist of aluminum sheets, insulation, plywood and on top I put a layer of drywall.

Thank you everyone for your help and advice. I want to do everything safely. I don’t want to plug in a band saw or other power tool and turn the trailer into an electrocution box. That could ruin my whole day . . .

 

[odSteve]

Wow, so simple, I wonder why I didn't think of that. The nearest store that sells electrical hardware is 75 miles away in Klamath Falls, Oregon. I'll get a main lug only panel this weekend and hopefully install it next week after work providing the rain and hail lets up. I'll then post pictures here to get your feedback if I wired everything safely before I turn the 60 amp breaker on.
Is there any reason why I can't take the two top consecutive single breakers out and put the 60 amp double pole breaker there and the two single breakers in the main lug only panel? It would sure make wiring much neater rather than putting more wires down lower in that mess.
Definitely no hard feelings. For me this project is kind of exciting, in a way. Just wish the weather wasn't so cold already.
Thank you, Sir, for your understanding and help.
[automerge]1569905998[/automerge]
Another question: What is the difference between the 60 amp breakers in the two links below? Why is one $9.88 and the other $66.31? That's a big difference for the same product.

Eaton Corporation BR260 Double Pole Interchangeable Circuit Breaker, 120/240V, 60-Amp - Magnetic Circuit Breakers - Amazon.com - https://www.amazon.com/Corporation-BR260-Interchangeable-Circuit-Breaker/dp/B000BO6PCC/ref=asc_df_B000BO6PCC/?tag=hyprod-20&linkCode=df0&hvadid=198075247191&hvpos=1o4&hvnetw=g&hvrand=2898305687074851425&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9032687&hvtargid=pla-348114793153&psc=1

and

https://www.mscdirect.com/browse/tnpla/00105262?cid=ppc-google-New+-+Lighting+%26+Electrical+-+PLA_ssBWqZZ6E___164110844541_c_S&mkwid=ssBWqZZ6E|dc&pcrid=164110844541&rd=k&product_id=00105262&gclid=Cj0KCQjwz8bsBRC6ARIsAEyNnvpzAxcIS5A-sI84eh12f5WkraoxE2_XV7sRhqayOgvTW83GFLETS9kaAkAwEALw_wcB

 

[davesparks]

Interesting, I always thought breakers worked by sensing some type of electromagnetic field, not by sensing heat. Doesn't that make the breakers inherently very inaccurate or inconsistent in protecting the circuits? When its hot, say 95*F, the breakers will be much warmer and more likely to flip than when its below freezing at, say 10*F?

Different types of breaker sense current by different methods depending what application they are designed for and what you need them to do.

Your 'basic' breaker is normally a thermal magnetic circuit breaker.
As the name suggests these use both a thermal element and a magnetic element.
The magnetic element works by electromagnetism as you suggest, this element reacts quickly to larger fault currents but does not react to smaller overload currents. So this is the element that will trip the breaker if a short circuit occurs, such as cutting through the cable.

The thermal element is a bimetallic strip which the current passes through and has been calibrated to react predictably and accurately. This heats up as current flows through it and the more current that flows through it the hotter it gets,when it gets too hot it trips the breaker.
So if you have a 20A breaker with 20A flowing through it the bimetallic strip gets warm but not hot enough to trip.
If 40A was to flow through it then it will gradually get hotter until it trips, if 25A flows through it then the same will happen but a lot more slowly so it takes longer to trip.

Yes ambient temperature does affect the thermal element of a circuit breaker, they are calibrated at a specific temperature and will behave slightly differently at higher and lower temperatures. Manufacturers will supply data on their behaviour at other temperatures if it is needed, but usually the difference is not enough to have a significant effect.

Manufacturers also advise that heavily loaded circuit breakers should not be installed next to each other as they will heat each other up and cause them to trip.

 

[Megawatt]

Wow, so simple, I wonder why I didn't think of that. The nearest store that sells electrical hardware is 75 miles away in Klamath Falls, Oregon. I'll get a main lug only panel this weekend and hopefully install it next week after work providing the rain and hail lets up. I'll then post pictures here to get your feedback if I wired everything safely before I turn the 60 amp breaker on.
Is there any reason why I can't take the two top consecutive single breakers out and put the 60 amp double pole breaker there and the two single breakers in the main lug only panel? It would sure make wiring much neater rather than putting more wires down lower in that mess.
Definitely no hard feelings. For me this project is kind of exciting, in a way. Just wish the weather wasn't so cold already.
Thank you, Sir, for your understanding and help.
[automerge]1569905998[/automerge]
Another question: What is the difference between the 60 amp breakers in the two links below? Why is one $9.88 and the other $66.31? That's a big difference for the same product.

Eaton Corporation BR260 Double Pole Interchangeable Circuit Breaker, 120/240V, 60-Amp - Magnetic Circuit Breakers - Amazon.com - https://www.amazon.com/Corporation-BR260-Interchangeable-Circuit-Breaker/dp/B000BO6PCC/ref=asc_df_B000BO6PCC/?tag=hyprod-20&linkCode=df0&hvadid=198075247191&hvpos=1o4&hvnetw=g&hvrand=2898305687074851425&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9032687&hvtargid=pla-348114793153&psc=1

and

https://www.mscdirect.com/browse/tnpla/00105262?cid=ppc-google-New+-+Lighting+%26+Electrical+-+PLA_ssBWqZZ6E___164110844541_c_S&mkwid=ssBWqZZ6E|dc&pcrid=164110844541&rd=k&product_id=00105262&gclid=Cj0KCQjwz8bsBRC6ARIsAEyNnvpzAxcIS5A-sI84eh12f5WkraoxE2_XV7sRhqayOgvTW83GFLETS9kaAkAwEALw_wcB

Steve yes you can take out the 2 singles out and put you 60 in them slots. 75 miles is a lot plus rain and hail wow it’s 90 + degrees I NC and so humid are they a Lowe’s or Home Depot bear you. As far as the price the only thing I can think of is that make sure you get a 60 amp double pole breaker with the same name brand
[automerge]1569932790[/automerge]

Steve yes you can take out the 2 singles out and put you 60 in them slots. 75 miles is a lot plus rain and hail wow it’s 90 + degrees I NC and so humid are they a Lowe’s or Home Depot bear you. As far as the price the only thing I can think of is that make sure you get a 60 amp double pole breaker with the same name brand

Steve good luck and stay in touch and that link was the right breaker.
[automerge]1569933443[/automerge]

Steve yes you can take out the 2 singles out and put you 60 in them slots. 75 miles is a lot plus rain and hail wow it’s 90 + degrees I NC and so humid are they a Lowe’s or Home Depot bear you. As far as the price the only thing I can think of is that make sure you get a 60 amp double pole breaker with the same name brand
[automerge]1569932790[/automerge]

Steve good luck and stay in touch and that link was the right breaker.

Sorry about my spelling, I should proof read before sending LOL
[automerge]1569933764[/automerge]

Steve yes you can take out the 2 singles out and put you 60 in them slots. 75 miles is a lot plus rain and hail wow it’s 90 + degrees I NC and so humid are they a Lowe’s or Home Depot bear you. As far as the price the only thing I can think of is that make sure you get a 60 amp double pole breaker with the same name brand
[automerge]1569932790[/automerge]

Steve good luck and stay in touch and that link was the right breaker.
[automerge]1569933443[/automerge]

Sorry about my spelling, I should proof read before sending LOL

Steve don’t buy the $ 66.00 breaker the difference is the rating of the breaker which won’t hurt or help you. Buy tha amazon breaker