ABB UniGear Digital, Инструкция по эксплуатации

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2.1.1 Current sensors
Current measurement in KECA sensors is based on the Rogowski coil principle.
KECA 80 C104 / KECA 80 C165
For dynamic current measurement (protection purposes) the ABB sensors KECA 80 C104, and
KECA 80 C165, fulfil requirements of protection class 5P up to an impressive value reaching
the rated short-time thermal current I
th
(31.5 kA or 50 kA). With KECA 80 C104 and KECA 80
C165 sensors, measuring class 0.5 is reached for continuous current measurement in the
extended accuracy ranges from 5 % of the rated primary current I
pr
not only up to 120 % of I
pr
(as being common for conventional current transformers), but even up to the rated continu-
ous thermal current I
cth
(1 250 A or 4 000 A). That provides the possibility to designate the
corresponding accuracy class as 5P400 and 5P630, proving excellent linearity and accuracy
measurements.
Figure 2: Current sensor KECA 80 C104 / KECA 80 C165
Technical parameters
– Continuous thermal current 1 250 / 4 000 A
– Rated primary current 80 A / 150 mV at 50 Hz or 80 A / 180 mV at 60 Hz
– Accuracy class 0.5 / 5P400; 5P630