Since winter is here I am more interested in getting the coolant heater circulator setup going.
This part of the speed controller rig will power the pump with external 240 volt power when the coolant heater is powered up.
The high voltage side of the pump controller is starting to take shape.
With the 277 volt primaries running off 250 volt power the transformer produced 15 open current volts.
I tried one 277 volt transformer wired straight onto an old head light with no bridge rectifier. It produced 9 volts at 2.5 amps and didn't heat up as much as I thought it might.
Then I put 2 transformers in parallel, 12.5 volts at 2.5 amps.
Seems like it should work, just as I was thinking it would.
All they need to do is turn the pump and not burn up.
So I put a bridge rectifier on the transformer secondaries and some alligator clips on the bridge rectifier - and +.
Then I unplugged the pump and put the bridge rectifier alligator clips on the plug prongs and plugged it in. It was trying to draw 5 amps at 8.6 volts of pulsed DC, until the bridge rectifier heated up.
This is only the prototype to obtain proof of concept using junk I have laying around. And it works. This is far from finished.
This is the rig while it is powering the coolant pump. The bridge rectifier was really heating up. I have a box of heat sinks and a tube of paste, so this wont be a problem.
If it looks dangerous, that's because it is. Yes that's a clothes dryer cord.
I will use a 120 volt relay to isolate the pump circuit while the high voltage is going so I don't back feed what limited DC power the pump has going to the rest of the electrical system.
I want to be able to plug the coolant heater in, go back in side where its warm and just leave the coolant heater and coolant pump to do their thing.