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uber39
Newbie

Joined: 31/10/2012
Location: Australia
Posts: 3

Posted: 03:57pm 04 Nov 2012

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Hello all and thanks for having me,
I already have wind ( old Dunlite 32v750w running at 48v )and solar ( 2.8Kw on trackers & 1.5Kw fixed on roof ) solar is grid tied, wind is sent to batts for off grid setup.
I'm putting together a small Mchp unit using a 4hp diesel as the prime mover. The question I've got is what would be the best gen configuration to use I'm chasing 20-25A x 48V.
I've tried both a .6 and a .8 wired at 2x7c and get 15A from both at 12-1500rpm. Any advice would be great.
Thank you all.
Ian

VK4AYQ
Guru

Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 03:38am 05 Nov 2012

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Hi Ian

From the figures you quote 15 amps at I assume around 55 volts + that would be the max capacity of your configuration, to get more you could tandem two on the same shaft.
I have spin tested the .8 rotors in the lathe and can get 750 watts at 1000 rpm after that they seem to saturate and not give much extra power, I was testing with original wiring set to delta, are you using star or delta? delta will give you more amps but lower voltage, but in your case when diesel driven rpm's are not an issue as in a wind turbine.

I have tried an old 32 volt generator and it will do 55 volts @ 30 amps all day on a little 3 HP diesel, have a look for one of those old units sitting in a farm shed.

All the best

Bob

Foolin Around

uber39
Newbie

Joined: 31/10/2012
Location: Australia
Posts: 3

Posted: 08:58pm 05 Nov 2012

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Thanks Bob,
I do have a couple of 32v gens a 25A and a 50A, also have a number of Dunlite 32/750 wind gen heads.
Just want to keep it as simple as pos.as in no fields to worry about, I can do mechanics and I'm quite happy to play with electricity. BUT when it comes to electronics I'm lost. I tried a car alt but after about 45min I managed to lose some of the smoke that they put into things, and we all know they don't work so well without their smoke javascript:AddSmileyIcon('

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Long story short, no money to spare and have the f&p motors sitting doing nothing and always wanted to try them.
Would I get more Amps with a 2x7c configuration ??

Ian

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