the brushless DC solar bore pumps
Brushless (ie, ECM) motors would be fine - but when I was last in the market, they were not available, or not at any sane price, from anyone I could get to talk to about them. Nowdays they'd probably be a good deal.
(In my specific instance, there's no power near the pump, I have to run it some 400 metres from the house. A 750 watt pump on DC would require either disturbing voltage, or much heavier wire).
Your 60meter head means roughly 90 psi of pressure. A centrifugal pump will be a very inefficient performer in this instance unless it has a lot of stages... maybe 10 or more for a bore pump diameter. ( 100mm)
I think mine is 4 or 6 stage, in a pump designed to fit down a 4" casing.
I have 60m vertical, and 400m of 40mm poly pipe, plus a non-return valve at the bottom that's worth a few more PSI.
Here's the water coming into the top tank - this is a 1.5" fitting the water is coming out of.
A progressive displacement cavity pump ( screw pump) is what we would use here
The diaphram and reed valves type positive displacement pumps are nothing but trouble, IMHO. Screws probably far better, but again - depends on what's available at the time!
I would resist the inverter idea, unless your going to pump it all at once, fast and short, then spend the rest of the day recovering... depends on the duty cycle
That's exactly what I do. I was sick and tired of running a low capacity pump that trickled water in like a leaky dunny and had to run 24/7 for weeks at a time to do anything. Now I run the new pump each afternoon for a week, fill up the top tank, then don't touch it for months
DC ( BLDC to be exact)... they both run inverters I know, but the DC three phase type is more versatile with differing cloud formations, and low down torque with poor light.... and NO batteries.
Absolutely, and that I'd agree with. I didn't catch the reference to brushless in earlier posts, which is why I piped up.
For medium pressure and high flow rate, the multi fan centrifugal ones are fine. For high pressure ( over 100psi ) the bore pump style seems the best fit... just throw it into the tank and your good to go.
Only warning with this (and it was my local pump expert friend who put me onto this one) - bore pumps expect (nay, require) water flow over them to keep them cool. Doing what I had intended to, and dropping a bore pump into a large tank and expecting it to work is an early death sentence for them. He STRONGLY advised me to make a cowel for the pump to give it the environment it expects. A lump of 4" pipe around it, capped off at the top, down the pump almost to the bottom of the motor.
All the little DC brush pumps of either the diaphragm or impeller type are best left on the shelf as Ross has forcast.
Thats my take on it anyway.
Reckon I'm with you on this one mate!