IG-267-EN versión 01; 07/04/2017
70
Protection, metering and control models
General Instructions
ekor
.rpa
The earth unit setting depends on the characteristics of the
line where the unit is installed. In general, the earth fault
values are high enough to be detected as overcurrent.
Even in isolated or resonant earthed neutral networks, the
fault value in transformer protection installations is clearly
different from the capacitive currents of the lines. The values
of the setting parameters must guarantee selectivity with
the main switch protections. Given the variety of protection
criteria and types of neutral used in the networks, a single
parameterisation cannot be indicated; each case requires a
specific parameterisation. For transformers up to 2000 kVA,
the settings below are given as a general example. It must
be ensured that they properly apply to the protections
upstream (general, line or main switch protections, among
others.)
Unit
Type
Designation
Value
Phase timed unit (1)
(UNIT_51)
Enabling the unit
Enable
ON
Starting up the unit
Pick_up*
58 (A)
Time curve
Curve
EI
Inverse curve time index
Index
0.20
Fixed time
Time
---
Torque control
Direction
OFF
Phase instantaneous unit (1)
(UNIT_50)
Enabling the unit
Enable
ON
Starting up the unit
Pick_up
404 (A)
Unit timing
Time
0.40 (s)
Torque control
Direction
---
Sensitive neutral timed unit
(1)
(UNIT_51NS)
Enabling the unit
Enable
ON
Starting up the unit
Pick_up
2 (A)
Time curve
Curve
NI
Inverse curve time index
Index
0.20
Fixed time
Time
---
Torque control
Direction
OFF
Sensitive neutral
instantaneous unit
(UNIT_50NS)
Enabling the unit
Enable
ON
Starting up the unit
Pick_up
10 (A)
Unit timing
Time
0.40 (s)
Torque control
Direction
OFF
Table 8.6.
Settings
Summary of Contents for ekor.rpa Series
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