IG-150-EN version 04; 03/10/16
118
Automation functions
General instructions
ekor.rps
5.4. Special recloser to operate with protections with single-pole trip
The recloser can be in one of the following 3 statuses:
1. Out of service. This status is reached by Control
command or by command of the protection console. It
does not reclose.
2. In service, three-pole mode. This status is reached by
control command or by command of the protection
console or by activation of digital input (if there is any
programmed for that function, which is optional). Its
operation is the same to the standard in the ekor.rps
protections except for the next aspects:
a. The ongoing cycle will start by actuation of the ekor.rps
itself or by activation of the “three-pole trip” input. The
inputs programmed as “general single-pole trip” are not
looked at.
b. The close command is conditioned to the input
programmed as “closure command” to be closed. This
input must be wired up to the output of a unit that
executes the Synchrocheck function.
c. The closure permission after trip programmed for “trip by
external protection” are applicable to the “three-pole trip”.
3. In service, single-pole mode. This status is reached by
control command or by digital input activation (if there
is any programmed for that function, which is optional).
Its operation is the following one:
a. The ongoing cycle starts by actuation of the ekor.rps
itself or by activation of the “three-pole trip” input or by
activation of the “general single-pole trip” input.
b. In the first two cases, the operation is the same as in the
case of the “three-pole mode” (the same times and closure
conditional on the closure permission).
c. If the first trip is single-pole, the closure time and the
reclaim time can be different of those for the three-pole
trip (other settings) and the close command (which is
three-pole) is given without taking into account the
synchrocheck function.
d. The closure permissions after trip programmed for “trip
by external protection” are applicable to both the “three-
pole trip” and the “single-pole trip”.
e. It is considered that in a cycle of closures there can only be
one single-pole and if there is, it must be the first one. The
second and subsequent are always three-pole. So unlike
the closure and reclaim times for three-pole trips, that are
4, there is one only closure time and one reclaim time for
the single-pole trip.
5.5. Syncrocheck
5.5.1. General description
The synchronism checking or “Synchrocheck” function
(function 25) is used to make the breaker closure conditional
to the compliance of the conditions established by setting.
Two digital outputs can be programmed as “closure
permission” and “synchronism failure” (their status is always
opposite), which are used in the operation circuit of the
close coil or as a signal for a closure automation function,
if there is any.
This function can be disabled (by setting or by digital input),
in which case there will always be closure permission.
The function compares the voltage signals of the same
phase at both sides of the breaker (that we will call A and
B). The unit compares directly the voltages received by its
analogue inputs, that is, the values of the secondary of the
voltage measurement transformers. It is supposed that the
transformation ratio of these is the same in the busbar and
in the line. There is no correction factor for the case in which
they are different.
The conditions to be closure permission are of two types:
1. Undervoltage permission. It is given permission if
there is no voltage in one or both sides of the breaker,
according to the following settings:
a. Permission if there is no voltage in A nor in B (YES or NO)
b. Permission if there is no voltage in A but there is in B (YES
or NO)
c. Permission if there is no voltage in B but there is in A (YES
or NO)
It is considered that there is no voltage in one side of the
breaker when the voltage measured is lower than the value
programmed as “minimum voltage” for that side.
In case there is voltage in both sides the function that acts is
the “synchronism permission”.
The analysis of the undervoltage conditions is only carried
out if the synchrocheck function is enabled, that is, it is not an
undervoltage protection (type 27) but an auxiliary element
to allow the closure in certain conditions, in which the
comparison between the busbar and the line voltages would
not give permission. As said before, if the Synchrocheck
function is disabled, the closure permission is given.
Summary of Contents for ekor.rps
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