Fan Law - Belt Drive vs Direct Drive
Fan Law - Belt Drive vs Direct Drive
(OP)
Can someone help on the question below?
If I change from a Belt Drive Roof Top Centrif Exhaust Fan to a direct drive will I save energy? See details
Old Fan: Motor RPM 1800, 1/4 hp and Fan RPM 1000
New Fan: Motor RMP 1000, 1/4 hp and Fan RPM 1000
The new fan has an ECM type motor that allows me to adjust the speed down to 1000 RPM, can I calculate power saved from the motor speed reductiion? horsepower2=(Speed1/Speed2)cubed * horsepower1. Or since the fan speed never really changes does horsepower savings not happen?
If I change from a Belt Drive Roof Top Centrif Exhaust Fan to a direct drive will I save energy? See details
Old Fan: Motor RPM 1800, 1/4 hp and Fan RPM 1000
New Fan: Motor RMP 1000, 1/4 hp and Fan RPM 1000
The new fan has an ECM type motor that allows me to adjust the speed down to 1000 RPM, can I calculate power saved from the motor speed reductiion? horsepower2=(Speed1/Speed2)cubed * horsepower1. Or since the fan speed never really changes does horsepower savings not happen?





RE: Fan Law - Belt Drive vs Direct Drive
Possibly some trivial difference associated with motor efficiency.
RE: Fan Law - Belt Drive vs Direct Drive
RE: Fan Law - Belt Drive vs Direct Drive
RE: Fan Law - Belt Drive vs Direct Drive
What is the annual operating cost of the 1/4 hp motor at its current load?
How much will it cost to make the proposed change?
RE: Fan Law - Belt Drive vs Direct Drive
RE: Fan Law - Belt Drive vs Direct Drive
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
RE: Fan Law - Belt Drive vs Direct Drive
RE: Fan Law - Belt Drive vs Direct Drive
The upshot is that you may need to adjust or replace the overcurrent protection relay if the motor is running somewhere near full output.