Need help to determine wattage of my submerged water pump

1/2hp is 372watts.
If you want to be more accurate, get a wattmeter.

a 1/2 hp sump pump requires 1050 watts or 2100 starting watts

https://powerequipment.honda.com/genera ... tion-guide

Its a Well pump, not a sump pump.

The 4DQ-0513 is just the pump end, Its a 1/2HP 9gpm max. You need the model number off the motor to find the amp rating. But generally a 1/2HP 4" submersible motor will draw around 1000 watts

thank you for the input everyone.
Sadly I can't get more info on the device; its 150ft down the well :-)
So sounds like +-1000w running which does make sense.

Knowing that 1 HP is 746W then 1/2 HP is 373W. And There is a difference between HP and BHP.

If you know the load in AMP the formula is volts X Amps. 240 Volts X Amps = watts

You said you took a picture of it - where is that?

A 1/2HP water pump uses a LOT more than 373W. I have a 1/2" jet pump for lake water intake at my cottage, running on solar.

I run with a 4000 watt Schneider inverter. My pump is wired for 120v. At start, AC motors can spike 2-3x their running watts, and my 1/2HP motor draws a solid 750-800 watts when running. My inverter handles the surge no problem.

If you're on the grid and just want running water during a power outage, don't waste your time with solar. You'll spend a fortune. Buy a generator, wire it into your home and have whole-home backup power.

You'll spend thousands on a solar setup to run that pump.

The other thing I did to reduce the frequency of my water pump runs, so I can better manage the draw from my solar system, was install larger pressure tanks for increased draw-down. It's better for a water pump to run once for 15 minutes vs. 3 times at 5 minutes each time.

We can have a couple of showers, wash dishes, flush toilets etc. without the pump running. This lets me flip the breaker on the pump at night if it's close to the 30PSI trigger that turns it on, so it doesn't drain the batteries too much when it's dark out (if they're already low). I have an antique pressure gauge plumbed in on the bathroom wall so I know the current pressure at any time.