Ormazabal ekor.rps User Manual

IG-150-EN version 04; 03/10/16
78
Protection functions. Description and settings General instructions
ekor.rps
4.9. Broken conductor protection
4.9.1. General description
It is a denite time protection unit. The starting value which
is set is, in per unit, the module ratio between the negative
and positive sequence currents.
I
2
=
Ia + a
2
• Ib + a • Ic
I
2
= Ia + a • Ib + a
2
• Ic
 


Where a=1|120°
The relay trips when the programmed time has expired
since the starting setting value is exceed. To be operational,
this unit requires that the current of any of the phases is
at least 0.3 A, and both the direct and reverse sequence at
least 0.15 A (secondary).
4.9.2. Setting ranges (6 tables)
Setting Min Max Step Notes
Enable
YES/NO/pickup
Pickup
0.10 0.50 0.01 Ir per unit. I
2
/I
1
Denite time [s]
0.05 300.0 0.01
These settings can be found in the console on the screen “Overcurrent protection (2)”. OPEN PHASE box
Table 4.15. Setting ranges
4.10. Phase characteristic voltage control (function 51 V/50 V)
The timed phase overcurrent protection function can be
controlled by voltage, in the way that the starting current
decreases if the voltage control is lower than the nominal
voltage. To activate this function the setting "voltage
acceleration" of the settings screen “overcurrent protection
1 – phases” (or by keyboard/display the PROTECTION-
CURRENT PROT.-PHASE TOC.- ACCEL. ENABLE) must be set
to "YES". (If it is set to NO, the eective settings are the ones
programmed in the time delay phase overcurrent unit).
The control by voltage has two possible operation ways,
depending on the setting of the "voltage control" on the
screen number 3 of the overcurrent protection settings
(or by keyboard/display in PROTECT. FUNCTION-PA.CRTLV-
ENABLE). If it is set to NO, the unit operates in control mode
1 and if it is set to YES, in control mode 2.
4.10.1. Mode 1 (51V)
The pickup current is controlled by the compound voltage V,
corresponding to that phase, used as control. This function
aects both levels of timing.
When the control voltage is 10 % of the nominal voltage, the
controlled pickup current is 10 % of the programmed value.
When the control voltage is 90 % of the nominal voltage, the
controlled pickup current is 90 % of the programmed value.
Between both values, the pickup current variation is lineal
in respect to the control voltage.
For control voltage values higher than 90 % of the nominal
voltage, the pickup current is the programmed one.

Ormazabal ekor.rps Specifications

General

Brand	Ormazabal
Model	ekor.rps
Category	Relays
Language	English