|
Posted by gomango on March 19, 2008, 11:15 am
Please log in for more thread options
> 96f6f4acf...@e6g2000prf.googlegroups.com:
>
> > I really cant move the batteries closer due to the fact that the power
> > shed is already designed and set up for solar and wind where it
> > currently is. Im only looking for 10 amps charging. I figure that 10
> > amps over a 24 hour period would be more than enough to keep up with
> > winter demands without installing aditional solar. My adversion to
> > running wires was the voltage drop over that distance. I am pretty
> > new to all this so if Im wrong, please let me know.
>
> Fair enough.
>
> But you can predict the voltage drops and design your wire
> run to minimise the drop or at least make it acceptable.
>
> Voltage drop is based on the resistance of the wire and the
> current flowing through it.
> Ohm's law gives: Votage(drop) = current * resistance.
>
> Resistance will depend on wire length and gage.
> There are tables available on the internet that will give
> you the resistance per liner foot of any given wire gage.
> So you use the tables to figure out your wire resistance
> and plug it into the formula.
>
> By observing the formula, you can see that reducing the
> current will reduce the voltage drop. That's why you raise
> the voltage. For a give amout of power you will get less
> current flow at higher voltages.
> Power is given as: Volts * Amps = Watts.
> So given the same power (watts) you will get half the
> current by doubleing the voltage. And therefor half the
> voltage loss in the wire.
ok, I will bum a walking tape measure this weekend, and get an
accurate distance from the creek to the batteries and compare numbers
with the tables on the net. As for voltage... would it be a terrible
loss to run a transformer to step up the voltage for transmission? Or
would I be better off running direct off the generator, and then worry
about stepping down the voltage at the batteries? I haven't tested
the generator to see what it puts out yet, so I'm not sure what I'm
dealing with. When the shaft returns from the machine shop, I will
get some voltage readings off the leads at various speeds. I see that
in a lot of other micro hydro projects, there is always one form or
another of some sort of resistor that voltage is shunted to when the
system is running idle. Can someone direct me to good literature to
read up on this? I need to know why and how this is done. It must be
important if it's on all systems. I even saw a system with a base
board heater used as a resistor. Granted, these were mostly
alternator systems I saw.
| 
Yahoo! 
Google 
Windows Live 
del.icio.us 
digg 
Netscape 
XML Sitemap