Best place to buy Spindle and VFD?

[Kitwn]

Oooops!
That should have been 30l/hour. 500ml/min which didn't seem like much to me at the time, especially as I'd measured 4 times that with a short 250mm stub of the 5mm tube from the same pump.
I have no problem with your calorific maths, it all looks fine to me.

One thing I do, which I think we exchanged some comments on in the 'plumbing...' thread I mentioned above, is leave the pump running continuosly when the VFD is switched on. This ensures the bearings get maximum cooling between sucessive jobs. This is done to avoid the 'Perth Transformer Effect'. A few years back I worked for the WA power utility company. If we had a sudden spell of hot days in summer there would be a rash of transformer failures on the third day...Maximum load is around 4pm when everyone gets home from work ( we tend to work 7 - 3:30 over here) and switches on their air-con. The transformers heat up on day one and cool down overnight, but start day two hotter than they started day one. Day two follows the same pattern. On day three the starting temperature is so high that by early evening there are plenty lof angry, sweaty poeple around and plenty of power company workers missing dinner but earning lots of overtime replacing burst transformers. That was a massive problem in 2003-4-5 with everybody fitting the ever-cheaper but more power-hungry refrigerative air-conditioning and peak demand changed from heating in winter to cooling in summer.

Kit

PS You never know what you might learn reading MYCNCUK!