Eaton EFX48 e-Fuse Series, Installation And Operation Manual

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EFX48-xx Series with RM3-340/440 Installation and Operation Guide
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IPN March 2019
3. The breaker curve starts operating from a 110% overload (i.e. 1.1 times the configured
rating)
4. For rating settings where the 250A and 550A fast trip limits are above the 1000%
nominal overload, between the 1000% overload and the ultimate trip point the trip time
is nominally <10ms
5. The breaker curve closely follows the EFX48 curve on the graph above (red line).
6. There is a discontinuity between the 400% and 500% overload conditions in order to
protect the EFX48’s thermal fuses under normal overload conditions
Examples:
1 If a load output has a rating of 10A and a load of 40A is applied (i.e. the load is 400% of
rating) then the expected trip time is 700msec (from the red EFX48 line on the graph).
2
If a string connection has a rating of 30A and a discharge current of 60A is applied (i.e.
the load is 200% of rating) then the expected trip time is 6.5seconds (from the red EFX48
line on the graph).
3
If a load output has a rating of 5A and a load of 100A is applied (i.e. the load is 2000% of
rating) then the expected trip time is < 10msec (see note 4 above).
4
If a load output has a rating of 15A and a load of 300A is applied (ie the load is 2000% of
rating) then the expected trip time is < 100usec (see note 1 above).