4-10
Protection and Control
BE1-951
Figure 4-7. Example 3 Using 79LO Logic to Modify Group Control
Setting Automatic Setting Group Control
Automatic setting group control settings are set at HMI screen 2.3 or through the communication ports
using the SP-GROUP command. Automatic setting group control settings are summarized in Table 4-4.
Table 4-4. Automatic Setting Group Control Settings
Setting
Range
Purpose
Default
sw_time
1 to 60
0 = disabled
Time in minutes that determines when a setting
change occurs once the sw_level setting is
exceeded.
0
sw_level
0 to 150
Percentage of the SG0 prot_ele setting that
must be exceeded for a setting group change to
occur.
0
ret_time
1 to 60
0 = disabled
Time in minutes that determines when a return
to SG0 will occur once the monitored current has
decreased below the ret_level setting.
0
ret_level
0 to 150
Percentage of the SG0 prot_ele setting that the
monitored current must decrease below in order
for a return to SG0.
0
prot_ele
51P, 51N, 151N,
51Q, 791, 792,
793, or 794
Determines when automatic setting group
changes occur. Time-Overcurrent elements 51P,
51N, or 51Q can be selected so that setting group
changes are based on load current. Recloser
Shots 791, 792, 793, or 794 can be used to switch
setting groups when the appropriate shot is
reached in a reclosing sequence. If one of the
recloser shots is entered as the prot_ele setting,
the sw_time, sw_level, ret_time, and ret_level
parameters are not required and should be
replaced with comma delimiters.
51P
