voltage sensing relays ?

hi everyone, I have tested and used voltage sensing relays, most are not suited to windmill control system. this is do to the operating voltage and cycle control type. I was called to check a problem with a guys system, he was using the voltage relay type control board. this was a ebay type unit sold for about 10 - 15$. these can be used but are not properly suited to windmill applications. they work by simply watching voltage and mostly to a single digit . they work but are crud at best. they do not watch the s.o.c  and most are again mechanical relay type, short life.  in a wind burst the system went dead. his system has vary easy access. we tested the output voltage of his mill on my test bench , the output voltage was 68 volts, this was a problem because the voltage sensing board specs say its voltage limit is 90 volts max. any wind bursts can increase voltage to failure point quickly and the relay on all boards iv seen are only 10 amp max. all in all not suited for wind use. if you burn 2 of these boards you could have bought a windandsunpower.com board and never have had any problems to worry about. ------- one piece of info---- many of the 440 amp systems being sold are controlled by these types of so called controllers. there a failure waiting to happen. this is food for thought. thanks for reading.