Question on wire size for 30a

RJsfishin wrote:
I'd pull #0 to a sub w/ a couple 50 amp breakers,....never know when 2 50 amp visitors mite show up at the same time:R.

Fixed it for you.

:W

I'd pull #0 to a sub w/ a couple 50 amp breakers,....never know when 2 50 amp visitors mite show up at the same time:R.

If you pull #6 go with 6/3 (over 8/2)for a future install of 50 amp service.

The Electricians used 8/3 but it usually comes in longer lengths 40 amp three strand. 125 ft roll should be about 125.00
6/3 55 amp three wire shouldn't be much more, and well I just always though too much is just about enough. :)

I wasn't thinking about amperages correctly.
Definately use the 6/3. 55 amp then you have the run. It is multi strand as both are and will carry the max load well.
Might as well, maybe, put in 50 amp service. The box is about the same price.
Hundred amp total max load use 4/3 wire. Two breakers in the house or separate panel. go with separate panel add another 100.00 but you're now cooking with gas so to speak.
Shouldn't be more than 20 bucks more.
Forget the 8/3 wire altogether.Or just use the 4/3 wire for now and conver to 50 amp when you want to.

MEXICOWANDERER wrote:
kellertx5er :)

Care to factor in high head A/C starting amperage with voltage drop? I've must have said this 10,000 times, NEC cares about protecting their ass and the underwriters. THEY DO NOT FACTOR IN LONGEVITY OF LOAD COMPONENTS. I wish people would take this into consideration. ENGINEERING for minimum total cost over a span of "X" years, should be a top concern. Try measuring high head draw, then come to your own conclusion.

Mex, my post was only meant to refute a mis-application of the NEC. Never implied that NEC requirements are the best one can hope for.

NinerBikes wrote: "This is not fiction, it is fact, no one does the proper maintenance, going down and tightening all the screws at an RV park, or changing out the female receptacles when they get worn out, from plugging and unplugging, and running A/C and microwaves, all summer long."

Not to disagree with you but the RV park I stay in over the summer months in Albuquerque, NM DID change out the 30 amp female receptacle at the pedestal on my request. When hooked up to shore power I ALWAYS have an easily visible volt meter plugged in to one of my 120 V duplex convenience outlets. One day I noticed that the system voltage was dropping into the 110 volt range without any substantial load on it. I went out and put my hand on the male plug at the pedestal and it was to hot to comfortably hold my hand on it. The male terminals appeared discolored from heat and the baklite (sp?) female portion was cracked. After a little chat with the park manager, the 30 amp female receptacle was changed out the next day. Problem solved!

You are right on in that RV pedestal receptacles take a beating over the years from constant plugging/unplugging, wind, moisture, impact, and just plain abuse. They simply wear out, then fail to make a good connection. It's not much, but, the monthly electric bill is affected by the KW spent heating the plug which serves no useful purpose.

Chum lee

enblethen wrote:
You must understand that between RV pedestals and the rig is not a branch circuit but a feeder circuit. There is different criteria.

What it's claimed, vs how it is potentially used, are two different matters. Burning the place down or overheating any electrical circuit is no good. Wires get hot, copper gets malleable, terminals then get loose, aggravating the amount of surface area flowing electrons. Enough cycles, with no one maintaining or tightening the screws, burns the place down. This is not fiction, it is fact, no one does the proper maintenance, going down and tightening all the screws at an RV park, or changing out the female receptacles when they get worn out, from plugging and unplugging, and running A/C and microwaves, all summer long.

It is so cheap, insurance wise, to slightly overengineer on wire requirements, so, to me, as a General Contractor, it's a no brainer. Slighty more efficient heavier gauge Wire is cheap compared to rework labor.

When I am in an RV park, microwaving a baked potato for 6 minutes, and my AC kicks on again and the lights dim in my TT, I KNOW it's not doing anything good for my AC unit, it, instead is shortening the life of the AC motor, capacitors, and windings on my AC unit. Who pays for that when it fails, sooner, rather than later? I do, not the cheap skate that wired the whole place on the cheap, to save a buck. Do you think I will ever return to that RV park when I know this? Only if I am a fool.

kellertx5er :)

Care to factor in high head A/C starting amperage with voltage drop? I've must have said this 10,000 times, NEC cares about protecting their ass and the underwriters. THEY DO NOT FACTOR IN LONGEVITY OF LOAD COMPONENTS. I wish people would take this into consideration. ENGINEERING for minimum total cost over a span of "X" years, should be a top concern. Try measuring high head draw, then come to your own conclusion.

You must understand that between RV pedestals and the rig is not a branch circuit but a feeder circuit. There is different criteria.

kellertx5er wrote:

NinerBikes wrote:
For runs under 50 feet, 10 gauge wire may be rated for a 30 amp load, but for continuous load, it is derated to 80% of it's value, or 24 amps. This is important to factor in if you ever decide to plug in an Electric car with an EVSE to recharge the car... your circuit is only rated 24 amps. You might want to think about future proofing your installation.

This does not apply to RV pedestals. NEC article 551.73(D) states "feeder-circuit conductors shall have an ampacity not less than the loads supplied and shall be rated not less than 30 amperes." Your RV was built with a #10 supply cord and meets the NEC, no reason a pedestal must have larger wire unless for voltage drop.

60 feet of #10 at 30 amps will drop 3.0-3.5% (3.5-4.0 volts).

You may say it doesn't apply, per NEC, but I can guarantee it, RV pedestals are being used by the electric vehicle crowd far from the inner cities in rural areas, constantly. Yes, even Tesla's plug in, when their superchargers are down, at the nearest RV park. As I said, future proof, plan ahead. Electric cars are coming, whether you like it or not, and they do need to have places to recharge.

Any electric vehicle will pull a constant long term full load for over 3 hours, through the EVSE when recharging. Which is why LADWP here in Los Angeles, who offers a rebate, is so anal about the wiring you install to a 14-50 NEMA outlet (RV outlet), and derating to 80%, so that houses and apartments don't burn down.

I didn't cut corners when I pulled 6 gauge for 50 amps, for a 14 foot run even though I get 244 volts and my e-motorwerks 40 Amp EVSE device will charge at about 10 kwh. Sure, I could have pulled 8 gauge, but I don't want to waste money buying electricity and turning it into heated wires inside my walls. All those watts used heating wire add up, if you recharge daily, and end up on your electric bill, you still pay for them, they do nothing productive for you.