Schweitzer Engineering SEL-351P - Page 65

Settings
SEL-351P Quick-Start Installation and User's Guide (Portuguese) 59
No. Setting Default Range Incr.
35 Ground trip precedence N Y/N
Ground trip precedence = Y:
• If the ground fault current is above the Min. trip - ground (No. 6) level at the time of trip, the
operations to lockout follows Operations to lockout - ground (No. 16).
• If ground fault current is below the Min. trip - ground (No. 6) level and
phase fault current is above
the Min. trip - phase (No. 5) level at the time of trip, the determination to go to lockout is controlled
by Operations to lockout - phase (No. 15).
Ground trip precedence = N:
• If ground fault current is above the Min. trip - ground (No. 6) level and
phase fault current is below
the Min. trip - phase (No. 5) level at the time of trip, the determination to go to lockout is controlled
by Operations to lockout - ground (No. 16).
• If phase fault current is above the Min. trip - phase (No. 5) at the time of trip, the determination to
go to lockout is controlled by Operations to lockout - phase (No. 15).
• Note: The Operations to lockout - SEF (No. 17) is independent of Ground trip precedence.
• This setting is hidden and set to N if Operations to lockout - phase (No. 15) = OFF, Operations to
lockout - ground (No. 16) = OFF, or the Operations to lockout - phase setting equals (=) the
Operations to lockout - ground setting.
No. Setting Default Range Incr.
36 Underfrequency
loadshedding
N Y/N
The Underfrequency loadshedding setting enables the underfrequency loadshedding scheme, if set to Y.
• If Underfrequency loadshedding is set to Y, enter the following two settings:
Setting Default Range Incr.
Underfrequency pickup OFF OFF, 40.10-65.00 Hz 0.01 Hz
The Underfrequency pickup setting determines the frequency threshold for underfrequency
loadshedding.
Setting Default Range Incr.
Underfrequency time delay 6.00 2.00-16000.00 cycles 0.25 cyc.
The Underfrequency time delay setting determines the time delay for underfrequency
loadshedding.
No. Setting Default Range Incr.
37 Demand meter time constant 5 5, 10, 15, 30, 60 minutes
The Demand meter time constant setting determines the thermal demand meter response time.