What is NOL BHP?
NOL BHP is a combination of two acronyms that stand for non-overloading brake horsepower. NOL BHP is the maximum power required for a pump to operate at any point along it’s performance curve.
Brake horsepower is the amount of power generated by a driver such as a motor or an engine. Centrifugal pumps require a certain amount of input power to operate, and this power value is also called brake horsepower.
The amount of brake horsepower required to operate a pump varies from one location along the pump performance curve to the next. When a pump manufacturer determines the amount of brake horsepower that will account for all possible operating conditions, that value is called the non-overloading brake horsepower or NOL BHP.
In most cases, electric motors are sized relative to NOL BHP. If NOL BHP of a given pump is 47 HP, the motor is typically sized for the next available increment – 50 HP in this example. In cases where it can be assured that the pump will only ever operate at a single point, the motor may be sized to cover just the BHP demanded at that operating point.
NOL BHP is one of the key factors confirmed during a pump performance test.