EFX48 e-Fuse System Operation 
 
 
Copyright © 2019 Eaton Corporation.  All Rights Reserved. 
IPN March 2019 
115
 
Output fail alarm 
Alarm trigger  When output is off and the measured current is greater than 3A the 
load fail alarm is raised 
Alarm cancel  The load fail alarm is cancelled when conditions that raised it have 
Action required  If this alarm does not self-clear then the EFX48 needs to be replaced 
Output disc alarm 
Alarm trigger  When any load is disconnected for any reason other than being in 
button state off or having tripped then the load disconnected alarm is 
Alarm cancel  The load disconnected alarm is cancelled when the condition for 
GPIO Digital Input alarms    
GPIO1, GPIO2, GPIO3, GPIO4, GPIO5 Digital input  1-5 alarms 
Alarm trigger  When any GPIO is set as a digital input and has been in the active 
state for greater than the DI dwell time (individually settable for each 
GPIO DI) then if set as ‘battery disconnect function’ this will be 
actioned, after a further time (global alarm qualification period) any 
set alarm and DO destination(s) will be actioned (outputs activated 
Alarm cancel  When a GPIO input has been in the non-active state for greater than 
the set DI dwell time then if set as battery disconnect function  this 
will be released, after a further time (global alarm qualification period) 
the set alarm will cancelled (outputs de-activated and SNMP message 
Rectifier alarms 
Rectifier single fail alarm (Rect fail) 
Alarm trigger  If one and only one  rectifier reports  that it is in a fail condition then 
the rectifier single fail alarm is raised 
Alarm cancel  When no rectifiers report a fail condition then the alarm  is cancelled 
Action required  Replace the faulty rectifier. Check the status of the LEDs on the 
rectifiers in order to identify which one is faulty. 
Rectifier multiple fail alarm (Multi rect) 
Alarm trigger 
If more than one  rectifier reports  that it is in the fail condition then 
the rectifier multiple fail alarm is raised 
Alarm cancel  When no rectifiers or only one report a fail condition then the alarm  is 
Action required  Replace both rectifiers 
Rect temp, Rectifier high temperature alarm 
Alarm trigger  If any rectifier(s) reports  a high temperature condition  then the 
rectifier high temperature alarm is raised 
Alarm cancel 
When no rectifiers report a high temperature condition then the alarm  
Action required  If the alarm does not self-cancel then replace the faulty rectifier. Check 
the status of the LEDs on the rectifiers in order to identify which one