Brake horsepower vs horsepower

Brake horsepower vs horsepower

Horsepower of a motor is what the motor is capable of delivering (the work it can do).  Brake horsepower is what you are actually making it deliver.  Using belt driven motors you have the option of increasing the load on a motor.  You should really not load the motor more than its listed horsepower.  But can you get more brake horsepower out from a motor than its listed horse power?  Yes, you can—although you should not.  It can be done because there is a safety factor built in.  It is called the Service Factor.  A motor listed as 10 HP is normally capable of delivering 11 HP (assuming a 1.1 or 10% Service Factor).  If you are using this motor in a belt-driven configuration you can load the motor beyond its listed 10 HP rating.  As you increase the brake horsepower of a motor beyond its listed HP, more current will be drawn by the motor and the motor will start to heat up.  If you have thermal protection on the motor you can safely venture into the service factor zone.  It is not recommended to increase the brake horsepower of a motor above its listed horsepower, but it can be done.  Obviously, this overloading cannot be done on direct drive motors--a fan (or a pump) with a direct drive motor will only operate at the motor rpm.

 Photo: Courtesy of http://www.rtftechnologies.org

Tags: brake horsepower exceeds motor horsepower; brake horsepower exceeding motor horsepower; brake horsepower more than motor horsepower; Can brake power exceed listed motor horse power?; Making your motor work harder; thermal overload protection; Service Factor of a motor; heating up a motor; direct drive motors; belt-driven motors