CHAPTER 6: SETPOINTS
S4 CONTROLS
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
6–115
Change setpoint group
The 350 relay has two identical setpoint groups- Group 1 and Group 2 for all protection
elements. Switching between these two groups is available automatically by assigning an
input (contact, virtual, remote, logic element), or via communications.
Group 1 is the default setpoint group. The relay can automatically switch from Group 1
protections to Group 2 protections, and vice versa, by setting up the switching conditions
under “Change Setpoint Group”. Under some application conditions, such as an
overcurrent element pick up, it may not be desirable to change setpoint groups. A setpoint
change can also be prevented if the breaker is open, so that a fault detected before a
reclosure will not cause a group change while the breaker is open. In such cases, the user
can set a condition under “BLK GROUP CHANGE”, where if asserted, the active setpoint
group will stay active, even if the input configured to switch to the other setpoint group is
asserted. For example if the active group was Group 1 at the time of a trip, the breaker
opens, and the input configured under “BLK GROUP CHANGE” is asserted, the relay will
maintain Setpoint Group 1, even if the input “SET GROUP 2 ACTIVE” is asserted. Vice versa,
if the “BLK GROUP CHANGE” input is asserted; the relay will not switch from Group 2 to
Group 1, even if the input under “SET GROUP 2 ACTIVE” is de-asserted.
The relay will default to Setpoint Group 1, if both the input “SET GROUP 2 ACTIVE” and the
blocking input “BLK GROUP CHANGE” are de-asserted.
Switching from Group 1 to Group 2 can be also initiated by the Autoreclose, or the Cold
Load Pickup functions. If the setpoint group selected in the Autoreclosure menu is different
from the active setpoint group, then the Autoreclosure function will force the relay to apply
the Autoreclosure selected setpoint group. The Autoreclosure function will then apply the
AR shot settings to the corresponding protections. The relay will revert to the previous
setpoint group after detecting the Autoreclosure resets.
Similarly, if “Enabled” and not blocked by the Autoreclosure, the Cold Load Pickup function
will force the relay to apply the protections of the other setpoint group, if the one selected
under the CLP menu is different from this, being in-service. The relay will revert to the
setpoint group used originally, after the CLP blocking function resets.
PATH
:
CONTROLS > CHANGE SPNT GROUP
SET GROUP 2 ACTIVE
Range: Off, Contact Input 1 to 10[8], Virtual Input 1 to 32, Remote Input 1 to 32, Logic
Elements 1 to 16
Default: Off
This setting selects an input used to change from Setpoint Group 1 to Setpoint Group 2,
when asserted. If no group change supervision is selected, Setpoint group 2 will stay
active as long as the “SET GROUP 2 ACTIVE” input is asserted, and will revert to Group 1,
when this input is de-asserted.
BLOCK GROUP CHANGE
Range: Off, Contact Input 1 to 10[8], Virtual Input 1 to 32, Remote Input 1 to 32, Logic
Elements 1 to 16
Default: Off
This setting defines an input that can be used to block changing setpoint groups. When
the assigned input is asserted, changing from one setpoint group to the other one is
blocked.
