If we were to install two Classic 250's in similar fashion to Halfcrazy's stacked configuration (in this case on a 14'-15' axial flux), am I understanding correctly that we would need a pair of (manual pg 53) 60A breakers on the output side and a pair of 30A on the input side?
I believe Ryan's is using 80A and 50A resopectively on a 17'-er with, I assume, two Classic 150's.
Also, I'm curious why you wouldn't want these tied as double-pole breakers, so if one tripped in this application so would the other?
Thanks for your help,
~kitestrings
you have to isolate both classics on the high voltage pv turbine side with diodes or rectifiers do not parelle the input side of stacked classics dont ask how I know burnt fets on one classic cheers Mike Johnson
I did not want to tie mine together because I wanted the ability to run one Classic if something happened to the second one the new Clipper will keep the turbine in check.
Ryan, Mike,
Thanks for the feedback, and your help (Ryan) with the breakers the other day.
I noticed in the schematic for the stacked units that you have two separte potted rectifiers - I assumed this was just to get the capacity needed. Mike is saying they need there needs to be two, paralleled on the AC input, but separting the DC sources to each Classic. Is this correct?
We're planning to build stud mounted diode/ rectifier(s) - I highlky favor them for longevity, and ease of repair. It should be an issue, but I'd like to know up front.
Thanks again,
~kitestrings
Basically there needs to be a diode on each Classic so the dc inputs are isolated from each other. I used 2 3 phase bridge rectifiers because we had them and it was easier for me.
Quotethere needs to be a diode on each Classic
A rectifier, I assume you mean? With the stud mounts it would be 3-heat sink (+/-), two sinks.
~kitestrings
I like the idea of using extra diodes for wind turbines that have AC 3-phase outputs (or more or less phases) because
they need a rectifier anyway, and adding more diodes (usually, the 3-phase bridge rectifiers) for each Classic does NOT
reduce the power loss.
At the moment, diodes are necessary with DC output turbines and PV arrays, but hopefully, some day, that requirement can go away
with true parallel of controllers. Not sure when that will happen, but it's is on the list.
boB
boB,
Thanks for the reponse. Haivng read this again, I can see I didn't word it very clearly (though I think you followed). There would normally be three diodes per heatsink, and two isolated heatsinks; one positive block and one negative. Six diodes forming the bridge rectifier.
In this case we'd need twelve, with separate DC outputs for each unit, though I supose pairs could share two larger heatsinks?
~kitestrings
Mike here I use two 3 phase rectifiers on one turbine for 2 classic stacking and the rectifiers are isolated from the heat sinks got them on Ebay for cheep sanrex I beleave for around 10.00 each rating was 100 amps 1200 volts can make some up on heat sinks but watch out for the reverse voltage rating of the diodes Tried the other way of using one for two classics does not work lets the smoke out :'( if confused call halfcrazy and we all will try to help on this board before troughing the switch so far seen 2 times the power with a 12' hughs turbine on one classic and have close monitoring with ryans homemade clipper 10-15 mph 850-1000 watts wow use to only get 400-500 does made a sweeter noise hum and blades move faster have set the voltage for 130 so wont get runaway if does not slow down will disconnect the input to the classic and leter free weel as can make more blades cheeper than classic smoke cheers Mike ps have seen 70 mph free weel on the blades and did not lose blades for 10 years now lost about 6 stators to burn outs. the classic now solves this problem everything now runs stone cold no line losses this week should be the test will keep update thanks and cheers Mike Eagle Energy Solutions LLC
Thanks Mike.
I appreciate you sharing your experiences - good, bad or indifferent.
~kitestrings