510 9424200994 Rev N
Setting Value
Description
Protection, Impedance,
Out of Step (78OOS)
Enables the 78OOS element
Reverse Reach
(secondary ohm)
Protection, Impedance,
Out of Step (78OOS)
Sets the tangential upper boundary to 10 Ω
Forward Reach
(secondary ohm)
Protection, Impedance,
Out of Step (78OOS)
Sets the tangential lower boundary to 30 Ω
Blinder A Offset
(secondary ohm)
Protection, Impedance,
Out of Step (78OOS)
Sets the offset from the vertical axis for
Blinder A to 5 Ω
Blinder B Offset
(secondary ohm)
Protection, Impedance,
Out of Step (78OOS)
Sets the offset from the vertical axis for
Blinder B to 5 Ω
Protection, Impedance,
Out of Step (78OOS)
Sets the angle for both blinders to 90°
Time Delay (ms)
Out of Step (78OOS)
Sets the amount of time required between
the blinders and within the mho
characteristic for pickup to 1,000 ms
Out of Step (78OOS)
Sets the amount of time before a trip is
issued when the element is picked up and
has passed through Blinder A to 1,000 ms
Protection, Impedance,
Out of Step (78OOS)
Sets the minimum amount of positive
sequence current required for trip to 5%
Protection, Impedance,
Out of Step (78OOS)
A trip will not occur if there is twice as much
(or greater) I2 as I1
Step 2: Use BESTCOMSPlus to configure the BESTlogicPlus programmable logic shown in Figure 314.
• Blocking is disabled.
• OUT1 closes for 78OOS Trip.
• OUT2 closes for 78OOS Pickup.
• OUT3 closes for MHO Pickup.
• OUT4 closes for Blinder A Pickup.
• OUT5 closes for Blinder B Pickup.
• Fault recording is enabled.
Step 3: Prepare to monitor the 78OOS function operation. Operation can be verified by monitoring
OUT1, 2, 3, 4, and 5 (see Figure 314).
Step 4: Connect and apply 2.0 A balanced three-phase current to terminals D1 through D6 and a
balanced 40 V three-phase phase-neutral voltage source to terminals C13 (A-phase), C14 (B-
phase), C15 (C-phase), and C16 (Neutral). All outputs should remain open.
Step 5: Slowly decrease the voltage until OUT3 closes (MHO pickup) and record the pickup. This
should occur at 34.64 V ±0.69 V.
Step 6: Slowly increase the voltage until OUT3 reopens and record the dropout. This should occur at
36.37 V ±0.73 V.
Step 7: Slowly decrease the angles of the voltage inputs until OUT4 (Blinder A pickup) and OUT5
(Blinder B pickup) close and record the pickup. For A-phase, this should occur at –73.32°
±0.35°. OUT2 (78OOS pickup) should close after approximately 1 second.
Step 8: Slowly increase the angles of the voltage inputs until OUT4 and OUT5 reopen and record the
dropout. This should occur at –73.05° ±0.35°.
Out of Step (78OOS) Test BE1-11g
To Next Page
Need help?
General
