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Arnold Kay
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Join Date: Mar 2010
Posts: 9

Generator

06/25/2011 7:11 AM

I would like to use a Generac 5735 and parallel l the two 30 Amp outputs. Is there any reason why I can not?
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PSB
Active Contributor

Join Date: Jun 2011
Posts: 10
#1

Re: Generator

06/25/2011 8:58 AM

Syncronise both the generators and then use. as you can not use power generated by different sources together as phase angle will not match.
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Arnold Kay
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Join Date: Mar 2010
Posts: 9
#2
In reply to #1

Re: Generator

06/25/2011 9:09 AM

I am only using one generator, it has two 30 Amp twist locks and a 50 Amp I want to put the two 30 Amp in parallel in the same panel.
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brich
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Join Date: Oct 2009
Location: sometimes Wales,UK.. was Libya, now Oman!
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#6
In reply to #2

Re: Generator

06/26/2011 7:51 AM

If i understand you correctly you have one generator, two socket outlets of 30amps on this generator, and you want to feed BOTH 30 amps supplies into a remote distribution board..Yes!

Identify the RED phase or "U" phase in each outlet and measure the voltage between them. If its ZERO, check the other phases for the same result. If all three phases give you ZERO then both sockets are connected in parallel.

If you cannot find or identify the phases in each outlet, or you are not of an electrical background, then put your tools away, find the yellow pages and call someone who can.

It may sound hard, but its the piece of advice that will save your life and your equipment.

And don't think that if you put TWO 30amps outlets together it gives you 60amps!

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Tornado
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Technical Fields - Technical Writing - New Member Engineering Fields - Piping Design Engineering - New Member

Join Date: May 2009
Location: Richland, WA, USA
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#3

Re: Generator

06/25/2011 10:37 AM

Aren't they already in parallel?

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Arnold Kay
Member

Join Date: Mar 2010
Posts: 9
#4
In reply to #3

Re: Generator

06/25/2011 3:45 PM

One is a three wire twist lock and the other is a four wire twist lock on separate breakers.
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Tornado
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Technical Fields - Technical Writing - New Member Engineering Fields - Piping Design Engineering - New Member

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#5
In reply to #4

Re: Generator

06/25/2011 3:53 PM

How is it wired "upstream" of the breakers?

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JOHN H VAN ALLEN
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Join Date: Apr 2010
Location: Dominican Republic
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#7

Re: Generator

06/26/2011 9:06 AM

In my experience with generators around this size I think you will find that the output is wired as 120/240VAC. This would be wired with two Line Output wires a Nuetral wire and sometimes a Ground wire and in this configuration you can draw 30Amps on each of the 2 120V Output wires or connect a 240Volt load across the 2 line outputs and again pull 30Amps maximum.

This means that the two 30Amp Line Outputs are out of phase and CANNOT be connected in parallel to give you 120V at 60Amps. Connecting them in parallel would be a DEAD SHORT CIRCUIT.

Some generator manufacturers allow optional restrapping of the outputs. This usually implies opening the generator compartment and either moving small straps or undoing and moving wires. I did this with an ONAN/CUMMINS generator one time where the client had only 120V loads and needed all the power on one phase.

If this is allowed and you do it be sure to double the wire guage for the jump from 30Amps up to 60Amps. ie 30Amps = #10AWG 60Amps = #6AWG (or higher if you are running long distances.

Regards

John
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tcmtech
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Join Date: Jun 2009
Location: South of Minot North Dakota
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#8

Re: Generator

06/26/2011 11:56 AM

Where I work we started selling the Generac line of portable generators. The 5735 is a 17500 watt 120/240 volt single phase machine which means its capable of around 72 amps per leg as is.

There is one large four pin socket located under the main control panel that will give you what ever the main breaker is rated for amps wise on each leg.

For what its worth Generac are poorly/unnessisarily over engineered, poorly built (bad connectors and wiring harnesses right from the factory) and over rated (26250 peak watts, maybe with a nitrus kit) but still you should be able to get at least 60 amps off either leg at 120 volts from the main power socket.
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Arnold Kay
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Join Date: Mar 2010
Posts: 9
#9
In reply to #8

Re: Generator

06/26/2011 5:40 PM

Guru:

Thank you for the information you sent. The 4 pin outlet is fused with a 50 A breaker right above it on the control panel I want to feed one panel from the 4 pin 50A outlet and then I would like to feed a second panel from the 30A 110/220 and the 30A 110.

Can I connect the two 30A outlets in parallel one leg will have 30A and the other leg would have 60A feed from the two outlets, is this correct?
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JOHN H VAN ALLEN
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Join Date: Apr 2010
Location: Dominican Republic
Posts: 189
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#10
In reply to #9

Re: Generator

06/26/2011 7:30 PM

When I answered you the first time I wasn't aware of the size of your generator but after following the thread I decided to look up your model and now see that its around 17KVA so probably two of the 120V 30A outlets could be connected in parallel but as was mentioned earlier be extra careful that these two points are in phase or else you will be in trouble. I tried downloading a schematic but got a FORBIDDEN message from the Internet. If you are able to download the schematic from where you are then do so. If you are unsure how to read it try here again putting the schematic here for us to see. And of course be careful and ask an electrician if your unsure.

John
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tcmtech
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Location: South of Minot North Dakota
Posts: 8376
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#11
In reply to #9

Re: Generator

06/27/2011 1:33 PM

What are you running that needs 60 amps at 120 volt single phase that cant be split off into two independent 50 amp 120 volt lines from the 4 pin 120/240 socket?
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Users who posted comments:

Arnold Kay (3); brich (1); JOHN H VAN ALLEN (2); PSB (1); tcmtech (2); Tornado (2)

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