Got this from a BIL

Can't like that last part!

 

Then this is an easy question to answer. The normal full load amp draw is usually listed on the nameplate attached to the pump motor. You need to know the FLA and it's also helpful to know if it's running on 120V or 240V current.

If it's a 120V unit, I'd be careful running it on a 240V capable generator. Even if the FLA is under the maximum rating for the generator, you could easily burn up one side of the alternator windings or constantly trip a circuit breaker on the genset. Why? Because to get 240V current, a typical residential genset uses a combined output from two 120V windings. So if you only have one 120V load, only half of the generator's capacity is available unless the unit also has a "120V/240V" switch that allows full rated output at 120V. Take your 4400w unit for example. Total output at 240V would be 18.3 amps but only 9.15 amps would be available from each winding. Something tells me your 1/2hp pump is going to draw pretty close to that 9 amps (7-9 amps or so) if it's a 115v single phase motor. Running at that 9 amps, while theoretically possible, isn't recommended unless you have another significant load to balance out the other winding.

If your pump is wired for 240V, then no worries, as that 4400w generator should run it quite easily.

 

Need the info off your well pump.

Edit: Does the genny have a 120V/240V switch or a dedicated 120V 30A outlet?

 

These units were sold by the gross in the late 90s. Homelite and John Deere both put there names on these things in various capacities.

I'm no electrickan but I've been around plenty of these little gennys for awhile now.

 

Arrgh, thar she be then.

115V motor, 9.7 Full Load Amps. That generator would likely run the pump but it would be maxxing out the windings on one side of the alternator unless there is a full power switch (usually labeled 120v/240v) on the unit.

One thing to keep in mind is that you won't actually draw the FLA rating of that pump motor unless your water pressure is very, very low. As the pressure climbs towards the cut-out limit of the pressure switch, the amps drawn by the motor will actually decrease.

 

That's what I was afraid of. Basic connections only.

Only half of the genny's capacity is available on either of the 120V outlets. Even if you use the 240V connection to power your home in an emergency, the generator's capacity is going to be split amongst each 120V leg, only a true 240V load will use both windings.

If you have no 240V loads that you need to power in an emergency situation, then you should be able to re-wire the stator windings in parallel to utilize the full 4400w at 120V. It's usually not a difficult thing to do and there's plenty of info out there on how to go about it. Before the days of inverter generators, the RV guys did it all the time.

Example:

Synchronous Generator Basics, Simple Guide to rewire your HEAD.

 

That genny has enough umph to keep you quite comfortable in an outage. Transfer switch and the 240V plug will work just fine as long as you try to keep the load balanced across the two windings. One thing to watch would be something like the wife's hairdryer, most don't realize the little bastages can draw 12 to 15 amps!

Converting the genny to 120V only output erases those worries in your case and it could be hooked to the house in the same manner, (single HD ext cord and a t-switch) without worrying about overloading one winding or any load balancing concerns.

 

Then you run smack into the limitations of the genny windings. It may work but you will have a heavily imbalanced load. Moving a couple wires in the gen head gives you the benefit of wiring up the transfer switch and not having to change anything down the road should you upgrade to a bigger genset or get a 240V well pump.