ZES ZIMMER LMG450, User Manual

Page: 242 / 306

Miscellaneous LMG450
242
230V *
)
(0.95A
mA * 54.625W
+
)
(230V * 0.95A
V 0. * 54.625W
+
0.95A * 230V
W
=
2 2
35 . 2 315 638 . 0
λ ∆
0020 . 0 =
λ ∆
This is the absolute maximum error (worst case) that can occur in the calculation of the power
factor. The typical error is two to five times better!
The relative measuring errors are:
% =
U
U
=
%
U
measure
137 . 0
∆
% =
I
I
=
%
I
measure
247 . 0
∆
% =
P
P
=
%
P
measure
16 . 1
∆
% = =
%
measure
78 . 0
λ
λ
λ
∆
To get the real error, the inaccuracy of display (1 digit) has to be taken into account:
U % =
V
230.0V
=
display
0 01
0 004%
.
.
I % =
A
0.95A
= %
display
0 0001
0 01
.
.
P% =
W
54.625W
= %
display
0 01
0 02
.
.
0.04% =
0.25
0.0001
=
%
display
λ
This results in the following measuring values:
U
trms
= (230.00 ± 0.32)V
I
trms
= (0.9500 ± 0.0024)A
P = (54.625 ± 0.638)W
l = 0.2500 ± 0.0020