How to connect my generator?
I have have a Generac GP15KW
House has Square D 150 Amp Panel
I want to use Interlock (square D) switch to connect the Generator to panel.
I have on generator the following.
NEMA 14-50 120/240 50 AMP (For loads up to 12KW) 60 HZ *
NEMA L14-30 120/240 30 AMP (For loads up to 3.6KW) 250V 60hz locking*
2 NEMA L5-30 125V 30 AMP (For loads up to 3.6KW) 60 HZ
20A 120V DUPLEX OUTLET
20A 120V DUPLEX GFCI
seems like no single receptacle puts out the full 15KW?
What do I need to utilize the maximum power of the generator?
Can I somehow use the 50amp and twist lock 30 amp together? *
Maybe a transfer switch for the 30amp with a couple appliance's that doesnít exceed 3KW or 30 ampís and 50amp interlocked to panel and don't exceed 12KW? I don't like this idea, but it may be my only option to get the full 15KW.
I need to know exactly what to buy?
Thanks in advance
Assuming the generator is really capable of 15kW, and that's not just an advertising lie, you will need to hard-wire it. There should be a terminal block somewhere in the generator for the connections. There also should be at least a 65A breaker that protects that terminal block. If there isn't, then there is no way to connect a single 15kW load to the generator - you would have to split the load between the 30A and 50A receptacles. If that's the case, then I strongly suspect the generator is not really intended to supply 15kW.
TonyMast, there is an easy way to do this. First you would install an interlock kit and connect a 50A inlet to the backfed 50A 2-pole breaker.
Now remember that 15Kw is a lot of power, the first question is if you really need more than 50A? If you do, then you most likely have a specific load in mind, right? Well, whatever that load is, you would connect with a smaller transfer panel, such as this: http://www.reliancecontrols.com/Prod...il.aspx?CSR302
Let's say you wanted to power an AC unit, you would hook this panel up and then run a 30A cord to it.
As for operating two transfer devices from 2 different receptacles on the generator .. that would be a first in my experience....and a very bad idea. What are you wanting to operate that requires you to need 15KW ?
You may not put two generator feeds into the same panel, here a 30 amp feed and a 50 amp feed from the two generator receptacles respectively.
But you could have two transfer switches isolating and feeding two subpanels (or feeding the main panel and isolating one subpanel) with one generator feed to each of these.
Or connect the 50 amp generator feed to a single transfer switch for the panel and get a 30 amp power strip with breakered receptacles (a kind of portable subpanel) to plug individual appliances in using extension cords.
I doubt that generator (or most portables for that matter) would last 100 hours at 100% rated load. I would just use the 50 amp receptacle and a 50 amp inlet and worry about more important things, like where to get enough gas to feed that beast.
So I could do this?
Thank you very much for the answer.
So I need,
For my 30 amp twist lock:
Sub panel with say 8-10 circuits with LINE-OFF-GENERATOR breakers. Rated 30amp 240V 3.6KW (does this need to be Square D or can I use GEN-TRAN)?
6 gage 4 wire with male NEMA L14-30 plug, female on other side (say 15ft.).
Outdoor weatherproof NEMA L14-30 Rated 30amp 240V 3.6KW male receptacle.
Would like to install a meter to this line to check on Wattage? (donít know which one to get or what they are called). I believe the GEN-TRAN comes with meter.
For main panel:
Square D Interlock kit. (Are they all the same? How can I tell which one to get)
Square D 50 amp circuit breaker to switch to generator power. Is this a special breaker or any Square D 50 amp Breaker?
6 gage 4 wire with male NEMA L14-50 plug, female on other side (say 15ft.).
Outdoor weatherproof NEMA L14-50 Rated 30amp 240V 12KW male receptacle.
Would like to install a meter to this line to check on Wattage? (donít know which one to get or what they are called)
I believe only the interlock and Generator breaker have to be Square D, am I correct?
A light above main panel with on off switch that will tell me when the grid is back on line. But need to turn it off for normal operations.
So when I lose power,
1). I start generator to warm up.
2). Turn off main breaker to house.
3). Turn on light to detect grid power back on.
4). Turn off all breakers Main Panel and Sub Panel.
5). Plug in 30 amp from generator to outside receptacle.
6). Plug in 50 amp from generator to outside receptacle.
7). Turn on Main generator breaker.
8). Turn on breakers in main panel one at a time pausing for 10 secs.
9). Turn on breakers to generator power on sub panel one at a time.
Check Watts meters as I turn on things in house.
Back on grid,
1). Turn off all Circuit breakers off.
2). Turn off Generator.
3). Unplug all receptacles from generator (generator is off and not connected to house in anyway).
4). Turn on main house breaker.
5.). Turn on all circuit breakers main panel.
6). Turn on all circuit breakers to LINE in sub panel.
7). put Generator away !!
I don't think the generator will be running 100% all the time. I just want to have the ability to use all of the power if I want/need. We lost power for 8 days (Thank you Sandy!). Would be nice to wash a load of cloths or cook some food (about 1500 watts per element).
1. The 30 amp panel can be any brand.
2. Use 10ga wire for the 30 amp subpanel. 6ga may be too big for the connectors.
3. Wattmeter is what you are looking for to measure watts.
4. Post the model of your panel and I can look up the kit part number or look here:
5. Any normal square D breaker will work (not GFI ACFI.)
6. Only the interlock and Generator breaker have to be Square D.
7. The light to know when power is back on might be a problem if you transfer the whole panel.
8. Running that generator 16 hours a day for eight days will consume over 250 gallons of gas. Got a place to put the five (5) 55 gallon drums of gas or are you going to use natural gas?
Thank you Auger,
I think the model number of the main panel is QO30M150
Cat. Number: QOC30U
I look evrywhere the cloest I got to the interlock was K-5010 from
$149.00! Does that sound like to correct one and correct price?
Nothing I read said this kit for this model?
One more thing and I'll leave you alone you've been a major help. The circuit breaker for the generator TO MAIN PANEL should be SQ D QO 50AMP, 2 POLE SINGLE, PHASE?
PS I think I was burning 1 to 1.25 gallons of gas per hour.
I should have come here before I purchased Generator!!
You should e able to get a Square D interlock for about half that price from Square D.
The QOC30U is the cover.
If your panel is indoor then this is what you want:
Thats right, 2 pole 50 amp single phase. Square D makes two types, Homeline, and QO. The QO is the one you want.
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