Ametek MX Series - Table 6-7: Formulas to Calculate R and L

User Manual – Rev BE AMETEK Programmable Power
MX Series 233
Definitions:
V
NL
= Measured RMS voltage under no load.
V
L
= Measured RMS voltage under load
I = Measured RMS current.
F = Source frequency (50 Hz).
∆Φ= Phase angle shift between load and no-load conditions. Record phase angle from phase meter under NL and L condition and
determine phase shift.
Formulas to calculate R and L component of output impedance:
R = (V
NL
* cos( ∆Φ ) - V
L
) / I
X
L
= (V
NL
* sin( ∆Φ )) / I
L = X
L
/ (2 * Pi * F)
Table 6-7: Formulas to Calculate R and L