Genset sizing question

[panzerjunky]

Hello Gents
I am looking at buying a very nice MEP005 genset it is 30KW 60 hours on the unit the gentelmen also has a nicer 15kw unit with 2 hours on the clock my question is price is about the same for each I want it for emergency power at my house as well as run some jobsite lighting elect jack hammers ect. and I have a 480 3 phase mill that I would like to run ( so I don't have to buy a Phase converter) and the wiring can be set up in either one to run 110 220 single phase or move the wires for 480 3 phase.

I am wondering if the 30KW is a little to big and I should go with the 15KW as it is my understanding these units like to run at about 80% load or you can wet stack the motor.
any advise or comments welcome.
Thanks Jerry

 

[Isaac-1]

How big is your house? Is it all electric? How many air conditioners, water heaters, electric heaters, etc.

Ike

 

[panzerjunky]

thanks for the reply
1400 sq feet no ac waterheater is gas as well the fau

 

[4x4 Forever]

If the cooker is not electric, the 15KW for the house should do you nicely.

It would depend on the mill or equipment you want to run on 3phase.

Just make sure that you do not hook the unit up so that when your electric is off, the genset backfeeds to the incoming electric lines from your electric provider. They dont look kindly at that as it can kill people as they think there is no power.

 

[Speddmon]

You better do some more checking into those generators. You didn't list the model of the 15 KW set, but the MEP-005a in it's original configuration only puts out 3 phase voltages. And they are a Wye configuration at that. The 3 phase voltages you will get are 208 volts 3 phase "Y" or 416 volts 3 phase "Y". It's highly unlikely that your mill motor will be a 12 lead motor which is what will be necessary to make it run on 416 volts. 480 volts is a Delta voltage, the motor may, or may not (?) run on it, but if it does it will not last long I'll bet.

As to the 15 KW...if it's an MEP series (MEP-004a I believe) that one is strictly 3 phase as well, in the original configuration. The only MEP series generators that are factory capable of 120/240 volt single phase operation are the 10 KW and lower.

 

[jas67]

thanks for the reply
1400 sq feet no ac waterheater is gas as well the fau

A 5KW or 10KW would be plenty.

 

[LanceRobson]

The MEP-004A and 005A are, in fact, 3 phase only. Both are prone to issues if you take power off only 2 legs (for instance, for you house) and don't load the 3rd leg. I think that if you look in either set's -10 TM you'll find that they warn in big bold letters against doing just that.

From your description the only other typical 220 Volt loads might be a well pump and a stove or range. Generally you want to size a generator for the largest possible combination of automatic starting loads (refrigerator, freezer, well pump etc) and ad some reserve for starting loads.

An online search for sizing a standby genetator would help but if there are no 220 Volt loads I'd suspect that any good quality 6500 Watt or larger generator would keep the lights on and the beer cold without going broke on fuel.

Lance

 

[emmado22]

Watch out for wet stacking with an oversized unit. With diesel generators, bigger is not always better.