[RE-wrenches] Wattage 1/2 HP vs 1HP septic pumps

[Windy Dankoff]

Hi Dana!

A septic pump is a special breed, a Godzilla-like creature evolved for sucking muck. Not something I would want to consider changing a motor on … known as, if I may extend the horror theme, Frankenpumping.

To reduce peak load, or overload potential, I would consider a load-delay relay (or whatever you would call it) that switches some other major load OFF when the pump comes ON. The major load being something that won’t be noticed if it stops for the minutes of time that the septic pump runs.

I hope that’s helpful. // Windy … since Bozo was in B&W



> On Oct 26, 2017, at 5:42 AM, re-wrenches-request at lists.re-wrenches.org wrote:
> 
> From: "Dana" <dana at solarwork.com <mailto:dana at solarwork.com>>
> Subject: [RE-wrenches] Wattage 1/2 HP vs 1HP septic pumps
> Date: October 25, 2017 at 7:37:41 PM MDT
> To: "'RE-wrenches'" <re-wrenches at lists.re-wrenches.org <mailto:re-wrenches at lists.re-wrenches.org>>
> 
> 
> Ok all you whiz kids, bozos, & bolos:
> 
> 
> 
> If I have a septic lift pump [off grid ouch] at 1HP/240 vac/8-amps to meet
> all the usual state required overkill in septic design & a ½ HP/240
> vac/4.9-amp pump would do the same job but it will take 10% more time to
> dose 800 gallons.
> 
> Powered by an 8 KW Outback Radian inverter.
> 
>> From a load point of view and a 240-volt 3 phase wild AC well pump limiting
> the overall surge and general wattage is the smartest move, but; Which pump
> will use less overall power? We are using 240 volt to utilize both inverters
> and drop the load on either half of the Radian inverter.
> 
> Is there a smarter lift pump to use? ECM motor? Permanent magnet?