Power Relationships
-
Upload
sylvia-edwards -
Category
Documents
-
view
26 -
download
1
description
Transcript of Power Relationships
Power RelationshipsPower Relationships
P = watts
S = volt-amps
Q = volt-amps of reactance
Power RelationshipsPower Relationships
Resistance (R).
Inductance Reactance (XL)
Capacitance Reactance (Xc)
Reactive PowerReactive Power
Rate at which energy is being stored and returned to the ckt Inductance temporally stores energy Capacitors temporally store energy
Measured in Volt-amps of Reactance Units VARS
Symbol is Q
Q=Ex x Ix
True PowerTrue Power
Rate at which energy is dissipated or consumed in the CKT The load of the ckt ex motor, light
Measure in Watts Units are W
Symbol is P
P=Er x Ir
Apparent PowerApparent Power
Combined effect of Power and Reactive Power
Measured in volt-amps Units VA
Symbol is S
S=E x I
Power Factor Power Factor
Ratio between power and apparent power
P.f. = P/S
Require the angle (θ) Angleθ = cos-1p.f
Power TrianglePower Triangle
POWER TRIANGLE
LAGGING WATTS
VO
LT
AM
PS
RE
AC
TIV
E
WATTS
VO
LT
AM
PS
CA
PA
CIT
IVE
POWER TRIANGLE
LEADING
P =
Q =
P =
Q =