2.3 Measuring Elements
All the three overcurrent elements and one earth-fault element are provided
with user configurable 1A or 5A current transformer inputs. The MK2000
settings are normalized to 1A. If 5A current transformers are used, the user is
required to connect the current transformers to the 5A block terminal inputs
and normalize all required setting values to 1A before entering it into the
relay.
For each measuring elements, there is one independent high-set and one
independent low-set. The elements' overcurrent or earth-fault low-set tripping
time current characteristics are selectable between inverse definite minimum
time (IDMT) normal inverse curve, long time inverse curve, very inverse curve
and extremely inverse curve. The overcurrent elements and earth-fault
element tripping time current characteristic curves are individually selectable.
The high-set tripping characteristic for both overcurrent element and earth-
fault element are of the definite time type. Instantaneous tripping is made
possible by setting the time to minimum.
2.4 Digital Inputs
The functions of this external binary inputs are
•Blocking the operation of one or more protection stages.
•Resetting a latched output relay in the manual reset mode.
The input can be both ac or dc source. For dc input, the positive (+) terminal is
34 and the negative (-) terminal is 35.
MIKRO
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