Relay Element Settings 2-31
SEL-300G Instruction Manual Date Code 20020206
Zone 2 Mho Diameter (OFF, 0.1–100.0 W , 5 A relay) 40Z2P = 13.4
(OFF, 0.5–500.0 W, 1 A relay)
Zone 2 Offset Reactance (-50.0–50.0 W, 5 A relay) 40XD2 = -2.5
(-250.0–250.0 W, 1 A relay)
Zone 2 Pickup Time Delay (0.00–400.00 s) 40Z2D = 0.50
Zone 2 Directional Superv. Angle (-20.0°–0.0°) 40DIR = -10.0
The Zone 2 element typically is applied as a time-delayed tripping function. Zone 2
diameter and offset setting guidelines are described below.
Zone 2 loss-of-field tripping typically is performed with 0.5 to 0.6 second time delay.
Set 40Z2D equal to the desired delay.
The 40DIR setting is hidden when 40XD2 < 0.
The 40Z2 Relay Word bit asserts without time delay when the measured positive
sequence impedance falls within the Zone 2 mho circle defined by the offset and
diameter settings, and below the directional supervision line, if used. The 40Z2T Relay
Word bit asserts 40Z2D seconds after 40Z2 asserts.
40Z Element Torque Control (SEL
OGIC Control Equation): 40ZTC = !60LOP
The loss-of-field elements are disabled when the 40ZTC SEL
OGIC Control Equation
equals logical 0. The elements are allowed to operate when the 40ZTC SEL
OGIC
Control Equation equals logical 1. With the example setting, the loss-of-field elements
are allowed to operate when there is no loss-of-potential condition detected.
Note: The loss-of-field elements require at least 0.25 volts of positive-sequence voltage
and 0.25 amps of positive-sequence current to operate.
Relay Word Bits
Relay Word Bit
Function Description Typical Applications
40Z1
Zone 1 Loss-of-Field Pickup Indication, Event Triggering,
SER Triggering, Testing
40Z1T
Zone 1 Loss-of-Field Pickup With Definite-
Time Delay
Tripping, SER Triggering
40Z2
Zone 2 Loss-of-Field Pickup Indication, Event Triggering,
SER Triggering, Testing
40Z2T
Zone 2 Loss-of-Field Pickup With Definite-
Time Delay
Tripping, SER Triggering
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