#2 aluminum wire is rated up to 75 (up to 100 in different temp rating but
still more than 50) amps per the 1999 NEC. A bigger concern is the second
line. Typically a four wire hookup is one ground, one neutral, and two OUT
OF PHASE hot legs. this is how you generate 220 VAC - each line to neutral
is 110 vac and they are out of phase ( one is positive when the other is
negative) so that there is 220VAC between the wires. If the system is
perfectly balanced there would be no current in the neutral leg, but with
most typical loads there will be current running back the neutral. I would
recommend replacing the 30Amp breaker with a two phase breaker - it will
cover two spots in the panel and give you both phases. This will probably
mean replacing the wiring as well to get you the extra conductor. If so my
personal paranoia says to go with copper wiring.
If you have questions you should check with a licensed electrician.
Mark Miller
> ----------
> From: jvanho01@tir.com[SMTP:jvanho01@tir.com]
> Reply To: jvanho01@tir.com
> Sent: Friday, May 07, 1999 10:15 PM
> To: shop-talk@autox.team.net
> Subject: Electrical Hookup
>
>
> For any of the electricians out there. I am in the process of changing
> the
> outlet for my motorhome from 30 amp service to 50 amp. I currently have
> #2
> aluminium wire hooked up to a 30 amp breaker. I plan on replacing the
> breaker with a 50 amp breaker. Will the wire carry this load safely? It
> is running about 100 feet. The other question I have concerns the other
> end of the wire. The receptacle that needs to be replaced on the other
> end
> is a four prong affair as opposed to the 3 prong for the 30 amp. My
> understanding is that the motorhome uses a split 110 volt system. One
> prong is ground, another is neutral, and the other two are hot. I am
> planning on splitting the hot wire at the outlet and running it to both of
> the hot legs. Is this correct? or do I need to run another line. The
> reason I think that this is correct is the fact that there is only one
> neutral wire. All comments and advice is welcome.
>
> TIA
> Jim V.
>
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