Accessories
4.9 EFB300 external function box
3VA molded case circuit breakers with UL and IEC certification
Manual, 01/2019, L1V30435333-01
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4.9.2
Power supply
The EFB300 external function box requires a UL Class 2, 24 V DC power supply and acts as
a power supply for the connected ETU. This allows the ETU to remain operational even after
a 3VA UL molded case circuit breaker has tripped.
4.9.3
Functions of the digital input and digital outputs
Functions of the digital input
Active alarms transmitted by the ETU can be acknowledged via the digital input.
Functions of the digital outputs
With the powerconfig software application, it is possible to selectively assign signals
transmitted by the connected ETU to the four digital outputs of the EFB300. powerconfig can
be accessed via the TD500 test device or by means of the COM800 or COM100 breaker
data server through the link to the communication system.
The following signals (dependent on the ETU) can be assigned:
●
All reasons for ETU tripping (L, S, I, N and G)
●
Overload alarms AL 1 and AL 2
●
Pre-trip alarm for overload protection
An alarm is output in advance of a trip event, allowing time for a load to be disconnected
before the main voltage ceases as a result of the trip.
●
Load shedding/load pick up
By means of the load shedding and load pick up signals, a load can be disconnected or
connected automatically depending on the capacity utilization of the 3VA UL molded case
circuit breaker.
●
Energy pulse (ETUs 8-series only)
An energy pulse (S0 signal pulse) contains information that a certain amount of energy
has flowed through the molded case circuit breaker. The data are transmitted by
weighted pulses, i.e. a specific number of pulses are transferred to represent one kWh
unit.
Settings for the energy pulse, see table on next page.
Example of energy pulse:
Energy meter source:
Active energy kWh
Pulses per unit:
10
Unit:
1 kWh
Pulse length:
100 ms
For a flow of 50 kWh:
500 pulses with a length of 100 ms each
