pplication Notes 
 
P74x/EN AP/N
1, P742, P743  (AP) 6-
 
Function Keys 4 and 5 are set to ‘Toggle’ mode and on activation of the key, the 
commissioning mode will be in service as long as the function  has been enabled in the 
“Configuration” menu.  The associated LED will indicate the state of the protection function in 
service as GREEN and YELLOW for the 50BF disable mode and RED for the Overhaul 
mode. 
9.2  Differential current display 
When the differential  currents are low, it is possible to force to 0 the value of these 
differential currents displayed in the column MEASUREMENT 1 & MEASUREMENT 2. 
When the differential currents of a zone are all lower than the threshold (on the 3 phases), 
the currents displayed are forced to 0.