Generator Load Calculations

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
The Generac Smart Modules detect the frequency of the power coming in. When it drops below the acceptable parameter (can't remember what it is right now), the module opens and removes the load from the generator. They can also lock out larger loads while the generator is running.
I am guessing the Generac generator controls deliberately drop the frequency rather than depending on the prime mover slowing down under load?

Sent from my Pixel 4a using Tapatalk
 

JoeStillman

Senior Member
Location
West Chester, PA
I am guessing the Generac generator controls deliberately drop the frequency rather than depending on the prime mover slowing down under load?
The generator WILL slow down under overload, just like when your lawn mower slows down in heavy grass. This drops the frequency, not the generator controls. (By rating units at 80% power factor, you usually run out of kW before you run out of kVA.) This makes under-frequency a good indicator of overload and under-frequency relays are often used for load-shedding.
 
Top