LEM A188506510, Руководство по эксплуатации

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39
If the thus measured value RE deviates from the RE value determined without clip-on
transformer by more than 5%, adjust the clip-on transformation ratio (tr)
correspondingly:
tr tr
R with clip on transformer
R without clip on transformer
new old
E
E
= ×
−
−
( )
( )
Example:
Your clip-on transformer has a transformation ratio of tr = 1000:1. The measurement
without clip-on transformer results in a value RE = 0,983
Ω
. With a clip-on
transformer a value of RE = 1.175
Ω
is measured.
The deviation thus reads (1.175 - 0.983)
Ω
= + 0.192
Ω
and referring to RE = 0.983 W
an error evolves as following :
100%
0192
0 983
19 5%
× = +
.
.
.
Ω
Ω
The new transformation ratio to be set calculates :
tr
new
= × =
1000
1175
0 983
1195
.
.