Instructional Literature
Page
114
Effective: May 2008
Instructions for the FP-6000 Protective Relay
For more information visit: www.eaton.com
IB02602004E
5.4.14 Autoreclose Logic Settings
The FP-6000 provides a very comprehensive yet flexible
autoreclose function that meets the requirements of different
applications.
The FP-6000 autoreclose function includes the following features:
•
Fixed and programmable reclose initiate options;
•
Maximum four reclose shots;
•
Four independent sets of overcurrent pickup settings;
•
Reclose shots per hour limit;
•
Adaptive maximum shots limit;
•
Auto zone coordination with downstream reclosers;
•
Anti-pumping lockout;
•
Programmable reclose blocking;
•
Consideration of External/manual closing into a fault; and
•
Manual/Auto reset lockout (front panel, discrete inputs,
communications).
The detail description of the autoreclose logic can be found in
8.12.
The settings for the autoreclose logic can be roughly divided into
five groups. The first group is concerned with the reclose initiate,
reset timers, blocking, lockout, sync supervision, shot control,
auto zone coordination supervision, etc. Most of the settings in
this group are straightforward however; one may need to pay a
special attention to those timers. The manual/remote close
blocking timer (T1) must be set long enough to allow the relay
adequate time to clear the fault when the breaker is closed into a
fault. The Run-to-Ready timer (T4) should be greater than the
maximum reasonable trip time for the relay to trip a fault with its
protected range plus breaker operation time and the power line
de-ionized time. The autoreclose failure timer should be set long
enough to allow the relay to have a complete four-shot reclose
sequence.
The other four groups of the settings are concerned with shot
protection settings and they are independent of each other. Each
shot group of the protection settings can be disabled by setting
the Breaker Off Time to zero. Maximum number of shots the
autoreclose logic can perform equals the first consecutive n non-
zero breaker off times. For n shots application where n can be
one to four, the Breaker Off Time settings in the first consecutive
n shot protection groups must not be set to Disable; if n is less
than four, the Breaker Off Time setting in the nth shot protection
groups must be set to Disable. Each shot protection group can
be based on the currently active setting group or any normal
protection group of the enabled setting groups that are
configured in the system configuration. Each shot protection
group modifies their pickups or delays of all the instantaneous
overcurrent and current unbalance protections. Each overcurrent
or current unbalance function can be blocked or unblocked with a
modified delay. The modified delay option is very useful if a fast
trip is desired when the breaker is reclosed into a fault. Each shot
protection group can also block or unblock power and Var
protections. Each shot protection group can modify their pickups
of the time inverse overcurrent functions, shifting the trip curve
left or right of the normal trip curve.
To coordinate with the down stream relay or recloser, all shot
protection groups can be based on one normal setting group or
multiple groups. For example, if one normal setting group is
used as a base for all the shot protection groups, the user could
block all instantaneous overcurrent, unbalance, power and etc.,
and modify some time inverse overcurrent functions to make
sure they are coordinated with those corresponding functions on
the down stream relays. If each shot protection group is
intended to use a different group of the protection settings, the
user could associate each shot protection group with a desired
normal setting group and make sure to block or unblock all
instantaneous overcurrent, unbalance, power and etc., and adjust
the pickups of those time inverse overcurrent functions.
AR Control
Autoreclose Control Function. It must be Enabled for the
autoreclose logic to be active. If it is Disabled, the autoreclose
logic will stay in AR_OFF mode.
ARInitiate
Autoreclose Initiate Option. The option 52CSa52b is referred to a
condition that both 52CSClosed (control switch closed position)
and 52b (breaker open) are on, which indicates that there is an
automatic or remote trip. The option 52b cannot distinguish
between the protection trip from the manual or remote trip. It
may not be a safe choice if an autoreclose is not desired for
manual or remote trip. The option Prot Trip can be used in case
52b is not available. In this case, the FP-6000 assumes the
breaker status with current only. When a protection trip occurs, a
reclose process is initiated after a fixed delay. The option Prot
Trip & 52b is referred to a condition that a protection trip followed
by a 52b being on. The protection trip includes overcurrent and
non-overcurrent function trips. If the setting NonOCTripRI is
disabled, the protection trip includes only overcurrent functions.
This option excludes manual and remote trips and it is the
default option. The option PLC79RI is to use the programmable
autoreclose initiate logic gate output to start the reclose process.
The PLC79RI logic gate needs to be programmed separately. The
last option is a user-defined reclose initiating signal through a
contact input, Ext79RI. All the options except Prot Trip require
the setting AR Ext Init to be set to Enable.
Note:
The user must make sure that external signals to the contact inputs
are wired correctly and the contact inputs related are configured properly.
Any incorrect wirings or configurations would result in undesirable
actions.
NonOCTripRI
Non OC Protection RI. Enabling this option makes the Prot Trip
initiate include non-overcurrent protections, otherwise it will
exclude them.
AR Ext Init
External Initiate AR. Enable or Disable external signals to initiate
the reclose process. If 52CSa52b, or 52b, or Ext79RI is selected as
the reclose initiate option, this setting must be enabled.
Rst Lockout
Reset Lockout Control. This setting dictates how the user can
reset the autoreclose lockout condition. There are seven options
for this control that allow the user to reset the autoreclose
lockout condition from the front panel (UI), or through a contact
input (CIN), or communication (COMM).