I need another dedicated 220v 20 A circuit. My current main panel has a 220v 30 A and two 110v 20 A circuits that are for the shop alone. So.. I’m picking up a small 220v cyclone that would run in synchronization with a large machine on the existing, lone 220v. Therefore another separate 220v is needed.
Problem… the current main box is maxed out and has no more double spaces for the additional breaker and there is no space to double up with slim breakers to get the space I need.
Question… Could I use the space that the current 220V 30 A is now installed and replace that breaker with a 60 A? Then run a #6 gauge 3 wire 3 from it to a small sub-panel next to it? In that sub-panel I would install a 220 v 30 A and a 220v 20 A and run the appropriate #10 wire out-bound from it to the receptacles for each machine (and yes.. I will use #10 even on the 20 A)?
Thanks in advance for any assistance…
Sarge.. jt
Edited 3/18/2007 12:26 pm ET by SARGEgrinder47
Edited 3/18/2007 12:28 pm ET by SARGEgrinder47
Edited 3/18/2007 12:29 pm ET by SARGEgrinder47
Replies
Yea you can do that. Just be sure to run you ground from the sub panel to your other panel and don't bond the neutral in your new sub panel.
There is no problem running a 10 ga. wire off your 20a breaker, it will allow better voltage transmission (less resistance in the wire), plus it will allow you to upgrade to a 30a if ever needed. By the way, I made an error when I wrote you before, a 30a trips at 25a, not 22.
What is the size breaker and wire feeding your present panel? It is always possible to swap that panel out for a larger one if it isn't too much hassle. Just remember to kill the feed before you do.
Chris.
Thanks for the reply CC. Had a question on that neutral wire but irrelevant at this point. Going to drop in a 100 A sub-panel and a electrician freind is going to wire from the main to the sub.
Once it is hot.. I will put both 20 A 110v from the shop and the 220v 30 A and 20 A 220v's in it. May add another 110v and run the shop lights so all shop is consolidated in one sub panel. I decided for the small difference in cost, go ahead and roll the dice on the 100 A sub!
Again... thanks very much!
Sarge.. jt
Edited 3/18/2007 9:22 pm ET by SARGEgrinder47
You're more than welcome my friend, always glad to help if I can. Doing the change over is the best way to go, you won't regret it one bit.
Your E friend can show you what I meant about bonding a neutral. In writing it would be making your neutral bar (where the white wires go) in continuity with the panel box itself. Different ways to do it with different panels.
Enjoy your upgrade and let the woodchips fly brother!!!!
Chris.
You might look at picking up a 200A panel rather than the 100A. The 200A panels are usually much cheaper, as long as the upstream breaker sized correctly for the wire used. As was already stated -- the grounds and neutrals must not be connected until you hit the main box. Another plus of using a 200A panel is that they come with a "main breaker" which is now a switch to power down the rails in the sub-panel with out going to the main panel. The 100A sub-panels usually don't have a "main" switch.
Greetings Leslie...
Thanks for your thoughts... I will mention that to my E (actually he did mention it to me briefly on a phone conversation) when he takes a look at my box and set-up this week-end. Once we reach agreement on what is the best route in my case, I'll accompany him to my cousin's electrical wholesale store and purchase the necessary box, wire, etc.
And of course I'll remind my cousin of the baby crib I made for he and his wife for their first born. Nothing like being in position to "pull in a marker" here and there. ha.. ha...
Regards...
Sarge.. jt
Chris,
It is very dangerous for you to be misinforming people that circuit breakers trip below their actual rated and certified trip points, and I know I have pointed this out to you in the past. This runs the risk that someone will misapply this information and attempt to utilize a larger circuit breaker than the safe rating of a circuit.
Circuit breakers are designed to carry 100% of their rated current levels without tripping, yet you are telling people the breakers will trip at 80% of their rating. If this is a topic that you do not fully understand, then I strongly suggest you perform an internet search for “circuit breaker trip curve”. For your convenience, I grabbed one of the first links I came across which explains this in fairly simple terms. You will also find similar documentation at the websites of most circuit breaker manufacturers.
http://ecmweb.com/mag/electric_sizing_circuit_breaker/
Rich,
Wow, you're so right. I don't know what I was thinking, but thank you for the heads up. My sincerest apologies to all.
Chris
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