Electro Industries Nexus 1262, Installation & Operation Manual

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Electro Industries/GaugeTech
Doc # E151701
13-1
Chapter 13
Nexus ® Meter Calculations
13.1: Measurements and Calculations
The Nexus® 1262/1272 meter measures many different power parameters. The following is a list
of the formulas used to conduct calculations with samples for Wye and Delta services.
Samples for Wye : van , vbn , vcn , ia , ib , ic , in
Samples for Delta : vab , vbc , vca , ia , ib , ic
Q
Root Mean Square (RMS) of Phase to Neutral Voltages : n = number of samples.
For Wye : x = an, bn, cn
Q
Root Mean Square (RMS) of Currents : n = number of samples
For Wye : x = a, b, c, n
For
Delta
: x = a, b, c
Q
Root Mean Square (RMS) of Phase to Phase Voltages : n = number of samples
For
Wye
: x,y = an, bn or bn, cn or cn, an
2
( )
1
X
n
x t
t
RMS
v
n
V
=
=
∑
2
( )
1
X
n
x t
t
RMS
i
n
I
= =
∑
( )
2
( ) ( )
1
XY
n
x t y t
t
RMS
v v
n
I
=
−
=
∑