Basler BE1-87G, Инструкция по эксплуатации

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9170800990 Rev M BE1-87G Testing and Setting 5-7
Target Indicator Test
If the relay is equipped with target indicators, verify proper operation of each phase when the relay is
tripped. Verify that the targets reset when the target reset switch is operated during a non-tripped
condition.
Auxiliary Output Test
Check output contact operation at terminals 2 and 5 of relays equipped with auxiliary output contacts.
Relays with style number xxx-xxx-xxx1x have normally-open auxiliary contacts. These contacts close
when the relay trips.
Relays with style number xxx-xxx-xxx2x have normally-closed auxiliary contacts. These contacts open
when the relay trips.
Power Supply Status Output Test
Relays with a style number of xxx-xxx-xxx6x are equipped with a set of power supply status output
contacts.
1. Apply operating power to the relay and verify that the power supply status output contacts (terminals
2 and 5) are energized open.
2. Remove relay operating power and confirm that contact closure occurs across terminals 2 and 5.
Push-to-Energize Output Test
If an output test switch is present (relay style number xxx-xxx-xxCxx) verify operation by depressing the
switch and observing that the trip output (terminals 1 and 10) and the auxiliary output (terminals 2 and 5)
cycle.
SETTING THE RELAY
The following recommendations are provided for selecting the current sensitivity switch setting. Figures 5-
3 and 5-4 show how this setting corresponds to the operating current pickup over the restraint current
range.
Assuming that the CTs on both sides of the zone (generator, motor, or reactor) perform identically,
operating current will be equal to zero. The sensitivity setting serves to accommodate dissimilar CT
performance, resulting from differences in CT quality, burden, and core remanence.
During normal operation, the pickup on the flat part of the operating characteristic (see Figures 5-3 and 5-
4) must exceed the difference in steady-state CT errors. The relay must also override the error
differences in the presence of dc components developed by external faults or switching. Currents will be
offset during external faults on generator applications, during motor starting, and during switching of shunt
reactors.
Out-of-phase synchronizing of machines will also produce offset components. These so-called dc
components will produce significant CT saturation. For high current faults, the relay relies on the 50%
slope characteristic to override large operating currents. Significant operating current can also be
developed at restraint levels that fall on the flat part of the characteristic if the offset component persists.
The sensitivity setting needs to be above this operating current.
Terms for Calculations
I”
d
Sub-transient current
N Total number of CT turns
N
a
Number of CT turns in use (for multi-ratio type)
R
I
One-way lead resistance in ohms
R
r
Relay restraint circuit resistance in ohms
R
w
CT winding resistance in ohms
NOTE
Relays with a style number of xxx-xxB-xxxxx have current operated targets.
These targets will operate only when a minimum of 200 mA is flowing in the trip
output circuit (terminals 1 and 10).