Schweitzer Engineering Laboratories SEL-700G Series, Инструкция по эксплуатации

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4.48
SEL-700G Relay Instruction Manual Date Code 20170814
Protection and Logic Functions
Group Settings (SET Command)
The relay includes a user-settable SEL
OGIC
control equation to disable the
distance elements, as well as the supervision by the LOPX loss-of-potential
logic and the load-encroachment function, to provide three-phase element
security under maximum generator loading conditions.
Set Z1C to define the forward (toward the system) phase distance reach
defined in secondary ohms. For distance element security under heavy load,
set the load-encroachment element (see Table 4.37). This eliminates load
impedance concerns when selecting the Z1C reach setting.
The Z1CO setting defines the element offset for the three-phase faults. When
the relay has current transformers located at the terminals of the generator, as
shown in Figure 2.18, you can apply an offset equal to the generator
impedance as backup protection for three-phase faults in the generator stator.
When the element is used to protect for a phase fault external to the generator
differential zone, you should apply a small offset to include the origin (zero-
voltage fault) in the tripping zone.
The Z1CD setting defines the Zone 1 element definite-time delay.
Set 50PP1 to its minimum value, unless a special condition requires a higher value.
Set Z1ANG equal to the angle of the transformer plus system impedance
defined by the Zone 1 reach setting. The relay places the distance element
maximum reach along a line at the angle defined by the Z1ANG setting.
Set Z2C to define the forward (toward the system) phase distance reach, in
secondary ohms. For distance element security under heavy load, set the load-
encroachment element (see Table 4.37). This eliminates load impedance
concerns when you select the Z2C reach setting.
Table 4.8 Compensator Distance Protection Settings
Setting Prompt Setting Range
Setting Name :=
Factory Default
System Backup
BACKUP PROT EN N, DC, V, C, DC_V, DC_C EBUP := DC
Compensator Distance
Z1 COMP REACH OFF, 0.1-100.0 ohms
a
a
Ranges and default settings shown are for 5 A CT. Multiply by 5 for 1 A rated CTs.
Z1C := 8.0
a
Z1 COMP OFFSET 0.0-10.0 ohms
a
Z1CO := 0.0
Z1 COMP TIME DLY 0.00-400.00 s Z1CD := 0.00
Z1 CURRENT FD 0.50-170 A 50PP1 := 0.50
Z1 POS-SEQ ANGLE 45-90 Deg Z1ANG := 88
Z2 COMP REACH OFF, 0.1-100.0 ohms
a
Z2C := 16.0
a
Z2 COMP OFFSET 0.0-10.0 ohms
a
Z2CO := 0.0
Z2 COMP TIME DLY 0.00-400.00 s Z2CD := 0.00
Z2 CURRENT FD 0.50-170 A
b
b
Range and default setting shown are for 5 A CT. Divide by 5 for 1 A rated CTs.
50PP2 := 0.50
b
Z2 POS-SEQ ANGLE 45-90 Deg Z2ANG := 88
21C ELE TRQCTRL SEL
OGIC
21CTC := NOT 3POX