Hello again one and all,
just wanted to let you know the results of getting the Air X down and having an engineery friend do the bench testing. below is the email
from Duncan telling us what is wrong:-
The unit in question - Air-x wind generator
was bench tested with a 750watt Makita power drill
in low gear
which has a top speed of 450 rpm
at a wrist breaking torque connected to the air-x
using a hex bit, at very low revs torque was low with the drill machine full power (which only achieved
about 300 revs) we measured 14v at just over 1 amp not a good return on the power inputted, the unit
was disassembled which showed slight corrosion
on the terminator screws and the bearing chewed out a bit
causing seal failure or vise versa, the regulator was removed checked the regulation FETs one was
shorted gate, source, drain- another has a high gate resistance (300 ohm) and the third is good .
I did check check the alternator first for shorts or dodgy bits but after a lot of revs at sea it's in perfect order
with no corrosion
on the neo magnets or stator metalwork or windings so it points to the FETs -IRF 2804
Don't know the cause of failure as the 2804 has heaps of headroom
on the specks maybe the gates got
a spike ?? maybe a zener on the gates could have helped maybe, I doubt it was back emf as the FETs are
internally protected or maybe the drive wave-form went silly from a software
issue just don't know!!
We sent this to Chris Reigner at Southwest Wind Power and his response was that we can replace the circuit board for US$ 168 + shipping
, also we are replacing the bearings two in front one in rear at US$36 & 37 respectively. Chris was really helpful even though our generator
is out of warranty and he was really prompt with his replies, we took this long as our friend Duncan is really busy. So for less than US$250 we can repair it and get it going again.
Thanks to all of you who responded to our plea and with offers of advice, we do appreciate it.
We are hoping to have the gen back up in a week or so.