Generator Output And Transfer Switch - Electrical - DIY Chatroom Home Improvement Forum

 DIY Chatroom Home Improvement Forum Generator output and Transfer Switch
 Register Blogs Articles Rewards Search Today's Posts Mark Forums Read

07-12-2011, 09:29 AM   #1
Member

Join Date: Jul 2011
Posts: 39
Rewards Points: 25

## Generator output and Transfer Switch

Hello,

I have a 120/240V generator which is rated for 7200W continuous, and has one L14-30 for 120/240V, one L5-30 for 120V, and one 20A duplex. The L14-30 connection has two 30A breakers on the generator panel - I assume one for each pole. So assuming this generator can push 60A @ 120V or 30A at 240V (or some combination), what is the best way to maximize the connection to the transfer switch? In other words, is the L14-30 a 30A feed or a 60A feed?

My issue seems to be that it seems silly to have a 30A transfer switch fed by a 30A generator feed when my generator is capable of 60A@120V.

It seems that I would use a switch like the GenTran 3026 or 3028, but how do I get the full 60A if needed?

Thanks,

Jeff

07-12-2011, 10:30 AM   #2
Member

Join Date: Mar 2011
Location: MA
Posts: 835
Rewards Points: 734

You're confusing watts and amps.

30 amp X 240 volts = 7200 watts.
60 amp X 120 volts = 7200 watts.

Between each hot leg and neutral (120 volts) on your generator you can draw 30 amps which is 3600 watts. Between both hot legs (240 volts) you can draw 30 amps, 7200 watts.

What you do is use the proper L14-30 connector to your generator panel. The panel distributes the power onto two buses. You can then put any combination of 120 volt and 240 volt devices, up to 7200 watts load. It is important that you try to balance the load equally on the panel. You can't for example, draw 4000 watts on one leg and 3200 on the other. You'll trip the generator breaker.

If you look at the Gentran 3026 for example, the watt meters are to help you balance the load. Note: they only read up to 3750 watts per leg, they don't read amps.

 07-12-2011, 10:51 AM #3 Member   Join Date: Jul 2011 Posts: 39 Rewards Points: 25 Okay I sort of figured that - but didn't realize I needed to balance the load. Balancing the load seems tricky to me since the appliances in use, and 240V well pump cycling could vary at any time. But I get the concept now. how close does it need to be? So assuming I wire as you stated, are the remaining receptacles on the generator available for use so long as I don't exceed rated wattage? I would assume they are. Thanks!
 07-12-2011, 11:17 AM #4 Member   Join Date: Mar 2011 Location: MA Posts: 835 Rewards Points: 734 The closer you can balance the better for the generator. The well pump, being 240 volt is already going to be balanced. The other receptacle should be available. Just watch your loading. Balancing the load is the most important thing with a small generator. You might put, for example, your boiler on one leg and your refrigerator on the other. Then some lights on one, lights on the other. The well pump and any 240 vac device is already balanced as it is on both legs.
 The Following User Says Thank You to AandPDan For This Useful Post: aquasport17 (07-12-2011)

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are Off Pingbacks are Off Refbacks are Off Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post robojoe_fl Electrical 4 06-08-2011 01:36 AM Rick5150 Electrical 19 01-20-2011 11:14 PM Isaac-1 Electrical 4 03-16-2009 08:45 PM Jeremy Hillary Boob, PhD Electrical 5 11-19-2008 11:36 AM caseywa HVAC 16 02-18-2008 10:14 AM

Top of Page | View New Posts