Latest Discussions : Electrical & Lighting

jgsensor

10:44PM | 10/08/05
Member Since: 09/30/05
2 lifetime posts
I currently have a 100A main panel with a 50A feeder to a subpanel located outside at a spa. I am adding a pond pump and outside lighting (1 20 amp circuit) to the spa subpanel. My problem is the feeder breaker in the main panel is a 50-20 quad and I can not locate a 70-20 quad to feed the subpanel and I don't beleave the 50A feeder would handle the extra load at the subpanel. The spa has another 50A GFI breaker in the subpanel also. I was thinking of adding another 100A subpanel in my garage which would be a foot or so from the main panel. I could then add a 100A feeder breaker to the new sub in the garage that would in turn feed the spa sub with a 70A breaker and also have 2 20 amp breakers that would be relocated from my main panel. Would this work and if so, what gauge wire would I need to feed the new sub in the garage. Or would it just be best to upgrade my panel to a 200A?

househelper

06:29AM | 10/09/05
Member Since: 03/31/05
265 lifetime posts
Increasing the breaker size to the spa subpanel would also require increasing the wire size to that panel. Chances are you can add the 20A circuit to the spa panel(as long as there is room in the panel) without problem. The pond pump and outside lighting loads are small and the spa should not draw over 80% of the circuit maximum.

Billhart

06:56AM | 10/09/05
Member Since: 04/25/05
1915 lifetime posts
I would do a demand load calculation first.

I suspect that you really need to upgrade to 200 amp service.

http://www.taunton.com/finehomebuilding/pages/bh0019.asp

http://www.selfhelpandmore.com/homewiringusa/2002/definitions/demandcalc/index.htm

Remember when you do this that for specifc loads (AC, diswasher, spa, etc, etc) that you use NAMEPLATE LOAD RATINGS and not the circuit ratings.


jgsensor

11:28AM | 10/09/05
Member Since: 09/30/05
2 lifetime posts
The wire to the subpanel is 6-3 and there are 2 empty slots in the panel. The wiring should be able to handle the extra load. I talked with the spa company who installed the wiring and subpanel and they are telling me that it will handle the extra circuit with the pond pump and lights as is. Can the 50A feeder be enough to handle the spa and extra circuit? That doesn't seem right.

househelper

05:26PM | 10/09/05
Member Since: 03/31/05
265 lifetime posts
The 6/3 is correctly sized for a 50A circuit. That should be sufficient for the spa and the light/pond circuit you want to add. The breaker amperages are not added together to determine the circuit size.

fool4jesus

07:59AM | 10/22/05
Member Since: 06/20/05
53 lifetime posts
I also am installing a 50A hot tub. I would appreciate any comments on the following installation plan. I have a 60A subpanel nearby. It would be a lot easier to put a 50A breaker in the subpanel and run it out to the hot tub's outdoor sub panel than run another line back to the main panel.

I don't *think* I'm going to get into problems on the subpanel with load. I made it 60A because it was originally feeding a workshop with 110 and 220 circuits, but we'll be moving the workshop, so in the future the subpanel will only have a feed a couple of light circuits. At least, that's the plan from "the boss" right now. If it changes I guess I can always upgrade the existing 60A sub panel.

I am assuming that there's nothing I need to do in the new or old subpanel different than the last subpanel install. Looks like the hot tub panel doesn't have a bonding bar - I guess because it's never a main panel.

Finally, I will want to run a low-voltage lighting system outside. How should this be hooked in - just put in an outdoor outlet or permanently wire it to a new 110V circuit in the hot tub panel? Do people ever put the low voltage transformer inside the house? It would be a lot easier to put it there - no worries about mounting it outside on the siding, etc.




Post a reply as Anonymous

Photo must be in JPG, GIF or PNG format and less than 5MB.

Reply choose button

Anonymous

Post new button or Login button
Register