Sub panel 100 amp from 200 amp main panel, is this possible?
lawsonw36
9 years ago
last modified: 9 years ago
Featured Answer
Sort by:Oldest
Comments (12)
Ron Natalie
9 years agolawsonw36
9 years agoRelated Discussions
Installing a 100A sub panel off a 200A main panel
Comments (7)Thanks to sierraeast for straightening my goof-up out & Bill,that's a pretty good detailed work-up about what I've got planned. I'm going to study it at length,but you confirmed my basic original thoughts about how to accomplish this. Your charts and guidlines will be very helpful as I fine tune this. The point about installing the panel in the garage/interior wall cavity was a great heads-up....I was going to do just that. If I surface mount the sub panel in the garage on top of the firerock(perhaps in a firerock plenum) then I should be OK ? I had planned to run all the garage wiring in conduit anyway. I should add the additional rooms(12' firewall between the garage/shop & living area) will be 8' ceiling height in an area that is 12' tall(this leaves a 3&1/2' loft/storage area above those rooms). This will also make those areas easier to wire/insulate/& run HIVAC plumbing. Thanks very much for the information.... back to the drawing board..LOL...Dave...See More200 amp panel for new basement: ground and neutrals on same bus
Comments (12)"I powered down the sub panel and put all the grounds on the left and the neutrals on the right. They are still bonded together as I only have three feeds form the main. " you are very likely to need to add a separate grounding bar to the panel, and possibly two (one on each side). the green bonding screw that ties the neutral bar to the box itslef must be removed. Some panels allow you to remove the bonding between the tqro strips so that one can be used for grounds, the other for neutral but this tends to make a real mess in the panel since every grounded circuit now needs to go separately to each bar. It is often worth the effort to add two grounding bars parallel to the existing neutral bars. This allows the neutral and ground for each circuit to be tied to the respective bars adjacent to the breaker feeding the hot for that circuit. It sounds like you need four #6 connections (though it might be possible to use a smaller ground line). The hots come from a breaker in the main, and the neutral and ground both come from the same point in the main but need to land on their separate bars in the sub. The reason ground and neutral are separated in sub panels is to prevent any current sharing between the ground connection back to the main and the neutral connection. Any voltage drop in the ground connection picks up the grounds in the sub-panel and the ground of every branch circuit is is supplying. Grounds are never supposed to carry current, except during a fault. You want the whole set of grounds to be as close to zero volts as possible....See MoreUpgrade to 200 amp panel or keep 100 amp panel?
Comments (5)the thing about upping the service is you run into other issues. i KNOW that inspectors in my area will try to, and usually will, force you to bring other items up to current code. a good friend had a bad panel replaced, the EC pulled a permit for it, and the inspector made them go back and GFCI the outdoor/bath outlets before he would sign off. heck nothing was touched on those other than disconnecting fromthe old panel and pluggin most of the same breakers back in the new one. but he insisted tha tbecause the circuit was "touched" it had to come up to current code. With 100 amp service, you are limited to about 5 circuits total. common misconception, totally wrong, but common. at my house i have all my 240v breakers in the outside panel. there are 2 100A breakers, 2 60 amp breakers, 4 50A breakers, 2 30A breakers. that is a total of 580A! do i have 600A service, NO. i DO have 300A service though( i posted before that it was 400, but a friend who is a sparky corrected me). 1 of the 100A breakers feeds my indoor panel which feeds all the 120v circuits inteh house. this is a 24 slot panel with 22 20A breakers in it(the whole house is wired with 12/2 even the lights). that is 440A worth of breakers! you can have 20000A worth of breakers on a 100A service. it is not the size of the breaker, it is the size of the actual LOAD that determines service size....See MoreConverting a 200amp main panel into a subpanel
Comments (4)A number of companies make a combination unit that is a meter can and a small panel (8-12 spaces, 16 -24 circuits) that have feed through lugs. All you need to do is run the 4 wire feeder from the new panel to the old, and make sure the neutrals and grounds are separated (neutrals must be isolated from the box) at the old panel. Unless there is a local rule that requires a disconnect at the sub panel it isn't necessary. If the existing panel has a main breaker you can use that for the local disconnect if you want one, but the main breaker in the new feed through panel serves as the required service disconnect and overcurrent protection....See MoreRon Natalie
9 years agolawsonw36
9 years agolast modified: 9 years agoThanks Ron......I have another question I have a whole house disconnect outside after my meter base. There is a panel run from that to go out to a shed that never was built. Can I run from this box to another box to power the appliances in my garage?here is a pic.
,
lawsonw36
9 years agoweedmeister
9 years agoRon Natalie
9 years ago- PRO
Taylor Electrical Solutions, LLC
8 years ago lawsonw36
8 years ago- PRO
Taylor Electrical Solutions, LLC
8 years ago 
greg_2015
8 years ago
Related Stories
KITCHEN DESIGNKitchen Confidential: Amp Up Your Storage With Pullouts
See 12 types of cabinet pullouts that make your cooking and cleaning items easier to find and use
Full Story
PAINTINGKnotty to Nice: Painted Wood Paneling Lightens a Room's Look
Children ran from the scary dark walls in this spare room, but white paint and new flooring put fears and style travesties to rest
Full Story
GREEN BUILDINGLet’s Clear Up Some Confusion About Solar Panels
Different panel types do different things. If you want solar energy for your home, get the basics here first
Full Story
GREEN BUILDINGGoing Solar at Home: Solar Panel Basics
Save money on electricity and reduce your carbon footprint by installing photovoltaic panels. This guide will help you get started
Full Story
GARDENING AND LANDSCAPINGPatio Details: Sliding Fabric Panels Filter the Light Just Right
Stepping up to the harsh sun and heat of the desert Southwest, this intimate patio is an exotic escape right outside
Full Story
REMODELING GUIDESHello Again, Corrugated Panels
Once-Shunned Material Finds Expressive New Role in Contemporary Homes
Full Story
HOUZZ TOURSHouzz Tour: From Overgrown Weeds to Picturesque Farmhouse Expanse
This once-neglected 100-acre South Carolina site now features a lake, a wood-filled farmhouse and a far-reaching view
Full Story
REMODELING GUIDES6 Must-Know Lessons From a Serial Renovator
Get your remodel right the first time, with this insight from an architect who's been there too many times to count
Full Story
REMODELING GUIDESFrom the Pros: 8 Reasons Kitchen Renovations Go Over Budget
We asked kitchen designers to tell us the most common budget-busters they see
Full Story
DOORSKnow Your House: Interior Door Parts and Styles
Learn all the possibilities for your doors, and you may never default to the standard six-panel again
Full Story
Ron Natalie