[RE-wrenches] Deep well submersible pump query

[James Jefferson Jarvis]

Wrenches,

I have a project that needs a deep well submersible pump. I want to find 
a pump that will be compatible with an off grid system, probably using a 
single or two in parallel Magnum MS4024PAE or MS4048PAE inverters. I 
usually using Grundfos SQ pumps for these applications. The soft 
starting SQ work wonderfully with the inverters with no brownouts during 
startup.

But, in this case, the well is too deep for the SQ pumps. Well company 
is specifying 2HP, 4" diameter. Well is likely ending up 600ft deep, 
probably 400 to 500' deep pump, and needing to supply 10 GPM when running.

Customer and I are most familiar with a standard pressure tank type 
system with pump turning on at low pressure and off at high pressure. 
Well driller, in an effort to provide system with a soft start, are 
encouraging a constant pressure system. I am not thrilled with the 
thought of the pump starting up constantly for somebody to brush their 
teeth or wash their. Or am I mis-understanding how constant pressure 
systems?

Any recommendations for a 2 HP pump system that will have minimal 
starting surge (ie run happily on inverter power)? My brief searching 
shows I can do a capacitor start system (three wire, with control box on 
the surface) and do somewhat better than across the line starting. Or I 
can do a 3 phase pump and then manufacturer / pump specific VFD on the 
surface ... at the penalty of huge $ cost and high idle power on the VFD 
control (65 watts in the case of a Franklin drive!). Or I can use an 
off-the-shelf 3 phase pump, and an off the shelf line reactor and VFD 
combination.

Thanks,


-- 
-James Jefferson Jarvis
APRS World, LLC
+1-507-454-2727
www.aprsworld.com