Odysseus99
Member
I've posted half a dozen questions the last few weeks on my pump installation. Thanks to Reach, Valveman, Craigpump, Texas and others for answers. I'm pretty close, just a couple more questions. Here's a summary so you have all the info:
400' deep well, 30gpm production, very clean water (a little iron, no grit) 290' static level, 6" steel casing all the way. Pumping to a storage tank, total dynamic head 350' or so. Will use a generator to operate pump at first, convert over to utility electric if/when I get the utility on the property. Might be on the generator a long time. Generator is a Briggs/Stratton 5550 watt 8550 starting watt construction generator. Generator is 350 feet from the well head, total wire length 750 feet. When/if the utility goes in the wire length will decrease.
My plan as of now- get a Franklin 1hp 2 wire motor and Grundfos 4" 7gpm pump. Could use 10gpm but that's a problem if the level drops. Run jacketed #8 or #10 submersible well cable from pump to well head, #8 xhhw-2 copper in conduit to the shed where the generator lives.
I think you'll see a lot of your advice in those decisions. Thanks for the help.
Questions-
1-If I'm using a generator, is it better for the longevity of the pump motor to use a 3 wire setup with running capacitors, rather than 2 wire? Reach seemed to think so.
2-If I went with 3 wire and located the controller at the well head (350' from genny), it would be exposed to the elements, rather than in a protected shed with the generator. Is this a problem for longevity of the controller/capacitors? Also, the AIM manual states that some controllers need to be close to the power source, but other types can be far from the source. What's your experience?
3-Is it a good idea to design in a little voltage drop in the wiring if only to bring the voltage closer to the rated 230v? Valveman likes to drop voltage enough to reduce starting torque. But 2 wires have less torque. For me the question is- on the long term is it damaging to the motor to operate it at close to 240v when it's rated at 230, or doesn't this matter? Maybe the answer is just that if you can use cheaper wire and be well within voltage tolerances, then use the cheaper wire. That's why I'm thinking #8 from generator to head, and #10 in the well, if the calcs work out. What are motor voltage tolerances? Plus or minus 10 volts, or 20, or 30? Does the difference in motor efficiency between 240 and 230v make much difference, if longevity does not?
The AIM manual is silent on both these issues. It gives no cautions about using generators except to use one big enough (mine is fine for 1hp), and talks about different wire sizes only to compensate for smaller existing wire to the well. But as Reach and Valveman said, you can use these different wire sizes to your advantage in a new installation to reduce cost or reduce starting torque. As an amateur electrician I'm reluctant to 'design in' voltage drop unless I'm sure of what I'm doing.
Thanks guys
400' deep well, 30gpm production, very clean water (a little iron, no grit) 290' static level, 6" steel casing all the way. Pumping to a storage tank, total dynamic head 350' or so. Will use a generator to operate pump at first, convert over to utility electric if/when I get the utility on the property. Might be on the generator a long time. Generator is a Briggs/Stratton 5550 watt 8550 starting watt construction generator. Generator is 350 feet from the well head, total wire length 750 feet. When/if the utility goes in the wire length will decrease.
My plan as of now- get a Franklin 1hp 2 wire motor and Grundfos 4" 7gpm pump. Could use 10gpm but that's a problem if the level drops. Run jacketed #8 or #10 submersible well cable from pump to well head, #8 xhhw-2 copper in conduit to the shed where the generator lives.
I think you'll see a lot of your advice in those decisions. Thanks for the help.
Questions-
1-If I'm using a generator, is it better for the longevity of the pump motor to use a 3 wire setup with running capacitors, rather than 2 wire? Reach seemed to think so.
2-If I went with 3 wire and located the controller at the well head (350' from genny), it would be exposed to the elements, rather than in a protected shed with the generator. Is this a problem for longevity of the controller/capacitors? Also, the AIM manual states that some controllers need to be close to the power source, but other types can be far from the source. What's your experience?
3-Is it a good idea to design in a little voltage drop in the wiring if only to bring the voltage closer to the rated 230v? Valveman likes to drop voltage enough to reduce starting torque. But 2 wires have less torque. For me the question is- on the long term is it damaging to the motor to operate it at close to 240v when it's rated at 230, or doesn't this matter? Maybe the answer is just that if you can use cheaper wire and be well within voltage tolerances, then use the cheaper wire. That's why I'm thinking #8 from generator to head, and #10 in the well, if the calcs work out. What are motor voltage tolerances? Plus or minus 10 volts, or 20, or 30? Does the difference in motor efficiency between 240 and 230v make much difference, if longevity does not?
The AIM manual is silent on both these issues. It gives no cautions about using generators except to use one big enough (mine is fine for 1hp), and talks about different wire sizes only to compensate for smaller existing wire to the well. But as Reach and Valveman said, you can use these different wire sizes to your advantage in a new installation to reduce cost or reduce starting torque. As an amateur electrician I'm reluctant to 'design in' voltage drop unless I'm sure of what I'm doing.
Thanks guys
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