ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
UL 508A SPACING
by ale348 - 03/29/24 01:09 AM
Increasing demand factors in residential
by tortuga - 03/28/24 05:57 PM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
1 members (ale348), 302 guests, and 14 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Joined: Mar 2003
Posts: 849
Y
Member
RV part not a Trailer park. Several Pedestals on a 4/0 Alum. Line. Breakers 200 amp. Pedestals are rated 125 amp. Lugs to pass though are termintated on the 125 amp buss. Each Pass through lug in a single unit(in & out one solid bar two term points) Since Terms never really pass through the bar JUST feed the bar(like a tap) Is the 125 amp rateing on the Pedestal OK. This is done on trailer parks all over the counrty. Other opinons Please

Stay up to Code with the Latest NEC:


>> 2023 NEC & Related Reference & Exam Prep
2023 NEC & Related Reference & Study Guides

Pass Your Exam the FIRST TIME with the Latest NEC & Exam Prep

>> 2020 NEC & Related Reference & Study Guides
 

Joined: Dec 2002
Posts: 337
S
Member
Interesting, as I have called out many of these and just worry about the wire sizes that can feed through (upwards of 250MCM main wire size on the brand I like), yet as I have known the mains are rated for only 125 amp.

I may be wrong, but I have kept to the following:

1- I have been using the 75 degree column only for any wire ampacity installed. This is probably not due to rating of the feed thru lugs which are likely rated for 90 degree, but due to the rating of the mains (the wire that feeds the disconnects) and is according to Mfg. literature.

2- I have assummed, maybe incorrectly, that the 125 amp mains is protected by the overcurrent devices in the pedestal and the feeder rules.

3- When I am over 250 (255 amp on the 75 degree of 250 MCM) amps on a feeder or using larger wire than 250 MCM, I tap out of handholes (grade level pull boxes).

It is possible that I have been having these installed incorrectly and there are overheating issues that I can not conceive. If so, the terminals are just oversized to accept large conductors due to voltage drop and we need to tap out of a pull box until the connected load (due to outside tap rules) is below 125 amp. This does not sound logical.

Our best source of correct information will be UL or other testing lab. If you are concerned enough, ask and let us all know, especially if I am wrong.

Shane

Joined: Mar 2003
Posts: 849
Y
Member
Most RV Pedestals Do Not Have Mains , 125 amp buss breakers for each outlet after that , could be a 50-30-20-or a 30-20
or a 20. Thats the way there build and go in.

Joined: Dec 2002
Posts: 337
S
Member
Correct, the mains that they refer to in my opinion is the wire from the terminal to the breakers.


Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5