User Manual

Description
2.4 Electronic trip unit ETU600
3WA Air Circuit Breakers
Equipment Manual, 05/2021, 92310000002-03
69
2.4 Electronic trip unit ETU600
2.4.1 Overview of variants
All the circuit breakers with integrated ETU600 electronic trip units have two independently
operating microprocessors - one for protective functionality and one for metering and
accessory functionality.
Function packages can be added to the ETU600 electronic trip unit to add protective
functions and additional measurement capabilities. This makes the ETU600 a future-proof
protection and measuring device in the age of digitalization.
The protective functions of the ETU600 comply with the regulations for electrical installations
and protect them against overcurrent and short circuit.
The optionally integrated metering function supplies the metering values for energy
management and can be referred to as a “power metering function” in a circuit breaker as
defined in IEC 61557-12. The functionality is equivalent to a power metering and monitoring
device.
The ETU600 electronic trip unit is available in the following versions:
• ETU600 LSI
This version has overload protection, short-time and instantaneous short-circuit protection
as basic protective functions. The basic protective functions do not require an auxiliary
power supply; they are supplied by the current flowing through the circuit breaker.
• ETU600 LSIG
In addition to the basic protective functions of the ETU LSI, this version offers ground-fault
protection, see Chapter Ground-fault protection GF (Page 55).
• ETU600 LSIG Hi-Z
Compared to the ETU LSIG, this version offers enhanced ground-fault protection, see
Chapter Ground-fault protection GF Hi-Z (Page 58).
The function scope of all versions can be extended by directional or enhanced protective
functions.