Schweitzer Engineering Laboratories SEL-421-4 - Table 5.73 POTT Relay Word Bits

5.128
SEL-421 Relay Instruction Manual Date Code 20171021
Protection Functions
Permissive Overreaching Transfer Tripping Scheme
ETDPU Echo Time Delay Pickup (cycles) 0.000–16000 2.000
EDURD Echo Duration Time Delay (cycles) 0.000–16000 4.000
EWFC Weak Infeed Trip Y, N, SP N
27PWI
a
Weak Infeed Phase Undervoltage Pickup (V) 1.0–200 47.0
27PPW
b
Weak Infeed Undervoltage Pickup (VFF) 0.1–300 80.0
59NW
b
Weak Infeed Zero-Sequence Overvoltage Pickup (V) 0.1–200 5.0
PT1 General Permissive Trip Received (when ECOMM = POTT or POTT2) SEL
OGIC Equation IN102 AND PLT02
PT3 Three-Pole Permissive Trip Received (when ECOMM = POTT2) SEL
OGIC Equation NA
PTA A-Phase Permissive Trip Received (when ECOMM = POTT3) SEL
OGIC Equation NA
PTB B-Phase Permissive Trip Received (when ECOMM = POTT3) SEL
OGIC Equation NA
PTC C-Phase Permissive Trip Received (when ECOMM = POTT3) SEL
OGIC Equation NA
EPTDIR Enable Directional Element Permissive Trip SEL
OGIC Equation NA
PTDIR Directional Element Permissive Trip Received SEL
OGIC Equation NA
COMZDTC Directional Element Communications-assisted Trip Enable SEL
OGIC Equation NA
a
Make setting when EWFC := SP.
b
Make setting when EWFC := Y or SP.
Table 5.72 POTT Settings (Sheet 2 of 2)
Setting Prompt Range Default (5 A)
Table 5.73 POTT Relay Word Bits (Sheet 1 of 2)
Name Description
PT Permission to trip received (ECOMM = POTT or POTT2)
PTA A-Phase permissive trip received (ECOMM = POTT3)
PTB B-Phase permissive trip received (ECOMM = POTT3)
PTC C-Phase permissive trip received (ECOMM = POTT3)
EPTDIR Directional element permissive trip enabled (ECOMM = POTT)
PTDIR Directional element permissive trip received enabled (PTDIR = Y)
COMZDTC Directional element communications-assisted trip torque equation asserted
(PTDIR = Y)
Z3RB Current reversal guard asserted (ECOMM = POTT or POTT2)
Z3RBA A-Phase current reversal guard asserted (ECOMM = POTT3)
Z3RBB B-Phase current reversal guard asserted (ECOMM = POTT3)
Z3RBC C-Phase current reversal guard asserted (ECOMM = POTT3)
KEY Transmit permission to trip (ECOMM = POTT or POTT2)
KEYA Transmit A-Phase permissive trip (ECOMM = POTT3)
KEYB Transmit B-Phase permissive trip (ECOMM = POTT3)
KEYC Transmit C-Phase permissive trip (ECOMM = POTT3)
EKEY Echo received permission to trip (ECOMM = POTT or POTT2)
EKEYA A-Phase echo received permissive trip signal (ECOMM = POTT3)
EKEYB B-Phase echo received permissive trip signal (ECOMM = POTT3)
EKEYC C-Phase echo received permissive trip signal (ECOMM = POTT3)
ECTT Echo conversion to trip (ECOMM = POTT or POTT2)
27AWI A-Phase undervoltage condition
27BWI B-Phase undervoltage condition