Applications
3.1 Use of the 3VA UL molded case circuit breakers in line protection
3VA molded case circuit breakers with UL and IEC certification
Manual, 01/2019, L1V30435333-01
117
5-series and 8-series electronic trip units
Parameter input via display unit
With 5-series and 8-series electronic trip units, it is possible to set more parameters and
scale the selection of parameters more finely than for 3-series trip units.
Parameters are set via the display unit and its buttons. This functionality is available,
however, only if a separate, dedicated power supply is connected to the molded case circuit
breakers.
Potential alternatives for this power supply:
●
24 V supplied externally via:
–
EFB300 external function box
–
MMB300 maintenance mode box
–
temporarily connected TD300 or TD500 test device
–
internal 24 V module
–
internal COM060 communication module
●
Current flow > 20 % I
n
in one of the 3 phases
A description of the parameter display can be found in chapter "Operator controls
(Page 84)".
Additional features of 8-series units
In addition to the features shared with 5-series trip units, 8-series units also offer:
●
An integrated voltage tap, plus an external voltage tap in the case of 3-pole molded case
circuit breakers
●
Additional sensing of power measurements (function requires an external 24 V supply)
