# Balancing load while using a generator



## wavewuver (Dec 13, 2011)

Purchased a Honda EU6500is generator as a portable backup supply for power outages. Going to hire an electrician to do the physical connections including an interlock device. While reading the manual for the generator, Honda emphasizes the need to "balance the loads" when the generator is running in the 240V mode. Apparently, there are two windings in the generator that individually feed the A and B sides of the load center and it is more efficient for the generator if the loads and somewhat equal on both the A and B sides.

My first question relates to 240V items such as my well pump. As I understand it, these items draw 120volts from each side of the load center. Therefore, all 240V appliances are automatically in balance. True?

My second question relates to balancing the 120V circuits. As it turns out, the lighting circuits are generally in balance and these will be used sparingly during an outage. But I have two items that are both on one side of the load center......the "refrigerator" and the "oil burner" that provides my heat and hot water. There will be times when both the oil burner and refrigerator will be running at the same time. The oil burner pulls about 6 amps and the refrigerator is a moderate size. Should I bother to place the refrigerator on the A side and the oil burner on the B side of the load center? I guess I don't know how much of an imbalance is tolerable.

The power from the generator will enter the load center via a 30amp two pole breaker with an interlock protection.


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## AllanJ (Nov 24, 2007)

Yes the 240 volt loads are "automatically" in balance.

Yes, change things around to put the refrigerator on the A side and the oil burner on the B side. That is about the best you can do.


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## Auger01 (Sep 13, 2011)

You do know that the A and B sides do not correspond to the left and right side of your breaker panel right?


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## J. V. (Jun 1, 2007)

In your panel you have even and odd numbered breakers. Even numbered breakers are on the same buss bar and the odd numbered breakers on the other. It will be very difficult to unbalance the load on the generator. All two pole breakers take an odd and an even breaker space. So none of the two pole breaker are any concern. Your generator is 6500 watt right? Do not over think this. You could balance the single pole breakers you use. Waste of time. Just see what can operate on generator power and what will not. What stuff can be operated at the same time. Consider the total load of the generator and turn on what you need. Unless your house is all gas and very small, you will never be able to use everything on generator power.

http://www.kohlerpower.com/resident...onNumber=13561&nodeNumber=1&contentNumber=103


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## wavewuver (Dec 13, 2011)

AllanJ said:


> Yes the 240 volt loads are "automatically" in balance.
> 
> Yes, change things around to put the refrigerator on the A side and the oil burner on the B side. That is about the best you can do.


That's what I thought too. Thanks for the confirmation.


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## wavewuver (Dec 13, 2011)

Auger01 said:


> You do know that the A and B sides do not correspond to the left and right side of your breaker panel right?


Yes I do. The load center alternates B and A starting at the top and working my way down. Five of the breaker slots near the bottom on each side can accommodate duplex breakers. Using duplex breakers is the only easy way for the electrician to free up 3 circuit slots since the load center is currently full.


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## wavewuver (Dec 13, 2011)

J. V. said:


> In your panel you have even and odd numbered breakers. Even numbered breakers are on the same buss bar and the odd numbered breakers on the other. It will be very difficult to unbalance the load on the generator. All two pole breakers take an odd and an even breaker space. So none of the two pole breaker are any concern. Your generator is 6500 watt right? Do not over think this. You could balance the single pole breakers you use. Waste of time. Just see what can operate on generator power and what will not. What stuff can be operated at the same time. Consider the total load of the generator and turn on what you need. Unless your house is all gas and very small, you will never be able to use everything on generator power.
> 
> http://www.kohlerpower.com/resident...onNumber=13561&nodeNumber=1&contentNumber=103


I liked your comment about not over thinking this issue. I think I was. The generator is 6500 watts (max).....I think it's 5500 continuous. I figured the electrician would move around a few circuits, try to balance a little and just get it going for emergencies.. I think I should be able to get my well, refrigerator, oil burner and a few lights powered. Plan to do an extensive test after the wiring is done and see if I stay within the capacity of the generator. Thanks for your comment.


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## Montrose439 (Dec 16, 2011)

I have a gas dryer so I had the 240 plug moved to the outside of the house and had a custom 240 volt plug for the connection. Just remember to turn off outside power before flipping the dryer fuse on.


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## brric (Mar 5, 2010)

J. V. said:


> In your panel you have even and odd numbered breakers. Even numbered breakers are on the same buss bar and the odd numbered breakers on the other.
> http://www.kohlerpower.com/resident...onNumber=13561&nodeNumber=1&contentNumber=103


Not on the panels I'm familiar with. _If place a 2 pole breaker on 2 an 4 how do I get 240 volts? _


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## brric (Mar 5, 2010)

Montrose439 said:


> I have a gas dryer so I had the 240 plug moved to the outside of the house and had a custom 240 volt plug for the connection. Just remember to turn off outside power before flipping the dryer fuse on.


That's just brilliant.


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## dmxtothemax (Oct 26, 2010)

If you can set up the loads so they are roughly balanced,
Thats good, but its really not that critical,
A moderate imbalance is tolerable,
Things like well pumps and fridges
are not critical in terms of supply voltage
and they should still work even if the voltage
varies around a little bit.


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## AandPDan (Mar 27, 2011)

Montrose439 said:


> I have a gas dryer so I had the 240 plug moved to the outside of the house and had a custom 240 volt plug for the connection. Just remember to turn off outside power before flipping the dryer fuse on.


What do you mean "custom 240 volt plug?"

Are you backfeeding? Do you have an interlock?


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## Techy (Mar 16, 2011)

gotta be a suicide(double male) cord.

extremely unsafe.


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## wavewuver (Dec 13, 2011)

dmxtothemax said:


> If you can set up the loads so they are roughly balanced,
> Thats good, but its really not that critical,
> A moderate imbalance is tolerable,
> Things like well pumps and fridges
> ...


I know I will have to live with some imbalance, just trying to minimize it. Lucky for me that critical appliances like the well pump run on 240, so imbalance is not an issue with the well. Same is true for the cooktop. I will try to use one burner and see what the load on the generator is. The Honda generator has a load readout which gives you a good idea of how much of the output capacity is being consumed. The gen puts out 5500 watts (continuous) which is quite a lot.


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## wavewuver (Dec 13, 2011)

Techy said:


> gotta be a suicide(double male) cord.
> 
> extremely unsafe.


Using an interlock is the minimum anyone should have. A transfer switch is even better.


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## jbfan (Jul 1, 2004)

brric said:


> That's just brilliant.


And dangerous!





I know, satire!


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## beenthere (Oct 11, 2008)

A connection as you are talking about is not code compliant. And is unsafe to do. It could back feed the through the meter and kill a linesmen.

Consult an electrician on how it must be done for safety.


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## dmxtothemax (Oct 26, 2010)

Are you using a properly set up transfer switch ???
And a properly set up feed in ???


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## Montrose439 (Dec 16, 2011)

AandPDan said:


> What do you mean "custom 240 volt plug?"
> 
> Are you backfeeding? Do you have an interlock?


Custom as it has two male ends. One for house and one for the portable generator which has a 240 volt outlet. 
My interlock is a external 100 amp breaker box. This has to be turned off before running generator. Generator fuse / curcuit breaker flips if u don't do it. Also I can't run whole house so ac and stove has to be turned off on the inner fuse box. 
Also it's only connected after a hurricane. I don't leave it plugged in and safer than running cord threw door as carbon monoxide made us sick one year.


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## Techy (Mar 16, 2011)

Montrose439 said:


> Custom as it has two male ends.



:furious:


Go buy a proper inlet receptacle,and a proper interlock. they dont cost that much money.

if the power was out, and your main breaker was on, you would be backfeeding the POCO grid with your generator, potentially injuring a lineman trying to repair the outage


Suicide cords are the stupidest things ever.


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## marksrig (Feb 27, 2015)

Auger01 said:


> You do know that the A and B sides do not correspond to the left and right side of your breaker panel right?


I see this thread is old but I came across your comment and seem to understand differently. The 4A and 4B circuits on the generator leave the 240V plug and are carried to the electrical panel via a double pole breaker. The double pole breaker energizes each 110V side of the panel buses. The DO correspond to the circuits on the generator as far as I can see it. Can you explain what you meant? Thanks


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## marksrig (Feb 27, 2015)

wavewuver said:


> Yes I do. The load center alternates B and A starting at the top and working my way down. Five of the breaker slots near the bottom on each side can accommodate duplex breakers. Using duplex breakers is the only easy way for the electrician to free up 3 circuit slots since the load center is currently full.


I see this thread is old but I wanted to see how your balancing went with your Honda. I have the eu6500 as well energizing my panel through a double pole breaker. As I understand the schematic, there is a Master and Slave winding on the generator corresponding to 4A and 4B circuits as noted in the ops manual. The 4A will be one side of the 110v bus and the 4B will be the other. The 4A and 4B are the hots on the 240v plug. They are also isolated from each other all the way to the busses in the panel. If one 110v leg has a pump and a fridge, the load will not be spread out among the Master and Slave windings. I don't think the previous comment was correct. What do you think?
Thanks


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## dmxtothemax (Oct 26, 2010)

It also depends on what on the other windings,
Having a well balanced load is not always critically important.


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## BruceS44!! (Feb 10, 2019)

I've read this thread as well as a few others here and on other forums and would like to add a question or comment.
Firstly I'm in Australia, on a large houseboat and have a Honda EU65is to have power when away from the marina.
I have a copy of both the EU, USA and Australian manual.
The Australian ones are different that others.
From the wiring diagram it's obvious that all 3 outlets are off a common wire/s.
It would be easy & compliant to get an electrician to simply remove the 3 outlets and replace with a RCD or RVD and a much heavier duty outlet.
I'm intending to direct connect the generator to the Outback inverter/charger with an inline isolation switch.
Oh! By the way the Australian Honda does not have any reset buttons above the outlets. You reset it by stopping & restarting the engine.


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## dmxtothemax (Oct 26, 2010)

Seeing three coils at first made me think maybe three phase,
But no the three outlets appear to be parallel on one circuit.
The two lots of coils appear to be in series,
This makes sense as this means the alternator is usable
For either 120v ( parallel ) or 240v ( series ).
So if the generator is being used for 240v ?
Then it is single phase output from the regulator.
So no balancing in needed.


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## BruceS44!! (Feb 10, 2019)

That's right but if just using the one 15A outlet to power my 80A X 24v inverter/charger the 15A plug tends to change colour & smoke a bit. (at the odd time I happen to turn on a few items plus charging)

Running one 4mm X 3 wire extension is much better!!?? (or direct connected)


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## dmxtothemax (Oct 26, 2010)

80A @ 24v is only 1920W,
19200w @ 240 is only 8A.
So if your 15A lead is smoking at only half its rating ?
Then you need to replace your lead !:surprise:


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