P74x/EN ST/N
1, P742, P743 
(ST) 4-
 
CONTENTS 
1.  SETTINGS  3 
1.1  Relay settings configuration  3 
1.1.1  “System data” column  3 
1.1.2  “Configuration” column (P741 Central Unit)  6 
1.1.3  “Configuration” column (P742 / P743 Peripheral Units)  8 
1.1.4  “PU Conf & Status” column (P741 Central Unit)  10 
1.1.5  Default settings restore  11 
1.1.6  “Date and time” column  12 
1.2  Protection settings  13 
1.2.1  Differential Protection Configuration (“Diff Busbar Prot” menu – P741)  14 
1.2.2  Differential Protection Configuration (“Busbar option” column – P741)  16 
1.2.3  Busbar Trip (87BB) or Central Breaker Fail BackTrip Confirmation (50BF) 
(“BB Trip Confirm” menu – P742/P743)  18
 
1.2.4  Dead Zone configuration (“Dead Zone Prot” menu – P742/P743)  19 
1.2.5  Non-directional Phase overcurrent protection  (“Overcurrent” menu – 
P742/P743)  19
 
1.2.6  Non-Directional Earth Fault Overcurrent Protection and External Fault 
Detection by High-Set Overcurrent (“Earth Fault” menu – P742/P743)  20
 
1.2.7  Circuit breaker fail and undercurrent function (“CB Fail” column – 
P742/P743)  21
 
1.2.8  CT Supervision (“Supervision” menu)  22 
1.3  Control and support settings  23 
1.3.1  Circuit breaker control  (“CB Control” column – P742/P743)  23 
1.3.2  “CT and VT ratios” column (P742 / P743)  24 
1.3.3  “Record control” column  25 
1.3.4  Measurements (“Measure’t setup” column)  26 
1.3.5  “Communications” column  27 
1.3.6  “Commissioning tests” column  29 
1.3.7  Opto configuration (“Opto Config” column)  33 
1.3.8  Control input setting (“Control input” column)  33 
1.3.9  Control input configuration (“Ctrl I/P Config” column)  34 
1.3.10  “InterMiCOM Comm and Conf” columns (P741 / P743)  34 
1.3.11  “Function keys” menu (P741 / P743)  37 
1.3.12  “IED Configurator” column (P741 / P743 only)  38 
1.3.13  “Control I/P (input) labels” column (P741 / P743 only)  39 
1.4  Disturbance recorder settings  40 
1.4.1  Central Unit P741  40 
1.4.2  Peripheral Unit P742 or P743  42