Siemens SENTRON 3VA2 - Page 126

Applications
3.2 Line protection applications of 3VA molded case circuit breakers
3VA molded case circuit breakers with IEC certificate
124 Manual, 03/2019, A5E03603177010-03
Advantages of 3VA2 molded case circuit breaker with ETU340 ELISA over fuses
● The extensive internal and external accessories of the 3VA2 molded case circuit breaker
can be used.
● When the EFB300 external function box is used, it is possible to output alarms from the
ETU, e.g. reason for tripping overload warning (overload or short circuit).
● Adjustable operating current for the overload release, thereby making it possible to use
smaller cable cross sections
● Selectivity to downstream fuses 1 : 1.6
● Can be closed again immediately after tripping and troubleshooting; no need to stock
replacement fuses
Note
The minimum short-circuit current at the line side I
‘‘
kmin
must be at least 7 times the circuit
breaker's rated current I
n
to trip the molded case circuit breaker after 5 s in compliance with
IEC 60364-4-43, DIN VDE 0100-430.
ETU340 ELISA 3-pole:
ETU340 ELISA 4-pole:
Line protection – function ELISA LI
The ETU340 ELISA electronic trip unit has:
● Simulation of the tripping characteristic of a fuse in a circuit breaker
● Adjustable parameter setting I
r
for overload protection (L)
● Increased, fixed parameter setting I
i
for instantaneous short-circuit protection (I) –
I
i
= 15 x I
r
● With 4-pole versions only: Neutral conductor protection (N) which can be deactivated
● Permanently active thermal memory, cannot be deactivated