Product Overview

3
“Feet Per Minute” K Factors
“Feet Per Minute” K Factors
Sensor Model K
FPM
SSS-10x2 3450
SSS-10x3 3300
SSS-10x4 3200
SSS-10x5 3200
Formulas
For Flow For Volume
DP = (FPM/K
FPM
)
2
FPM = K
FPM
x SQRT(DP)
CFM
K
FPM
x Area
CFM =
K
FPM
x SQRT(DP) x Area
Feet Per Minute in a VAV box equals the (relevant model’s) K factor
times the square root of the differential pressure (in “wc”).
Cubic Feet per Minute in a VAV box equals the relevant sensor
model’s K factor times the square root of the differential pressure (in
“wc”) times the cross-section area (in square feet).
NOTE: These formulas are for VAV controllers with built-in “differential pressure” sensors. The CSP-5000, KMD-7000, and BAC-7000 measure
velocity FPM directly—see their respective installation guides and application guides for more information.
NOTE: CFM (cubic feet per minute) = FPM (feet per minute) times the duct cross-section area (in square feet).
DP =
(
)
2