[RE-wrenches] Home Brew Frequency Switch

[Nathan Jones]

Mark,
I've seen lots of gensets wander that much and more. When inverters are throwing full amperage at a battery bank during bulk charge and the genset is set to 60hz it could easily be at 62hz at the tail end of the absorbtion charge when the load has tapered off.
Nathan Jones
Power Source Solar

On Tue Mar 1st, 2011 11:19 AM CST Mark Frye wrote:

>Folks,
>
>I am back on the project where I want to install grid tied inverters
>(Enphase) on a feeder located downstream of a generator and ATS.
>
>I have considered using a drop out contactor to isolate the inverters from
>the generator following a loss of line voltage.
>
>As an alternative, how well might it work to reset the generator frequency
>so that it is outside the inverter range? In this way the inverter would
>always see the generator as "bad" energy and therefore would never connect
>to the generator, only the utility.
>
>The nominal frequency range for the inverter is 59.3 to 60.5.
>
>What is the effect on the loads in the household if the generator frequency
>is adjusted to say 58 or 62 hertz? Would the higher or lower number be
>better? Would this fry everything in the house? I can't see that making a
>relatively small change like this would effect the overall impedance such
>that a problem with current capacities would be a problem. It seems like the
>frequency would be more of a problem for some devices.
>
>Anyone have experience with deliberately adjusting generator frequency away
>from 60 hertz as described above?
> 
>Mark Frye
>Berkeley Solar Electric Systems
>303 Redbud Way
>Nevada City,  CA 95959
>(530) 401-8024
>www.berkeleysolar.com 
>