Description
2.1 Overview - applications and portfolio
3VA molded case circuit breakers with IEC certificate
Manual, 03/2019, A5E03603177010-03
19
Selective contact system
With its contact system, the 3VA2 molded case circuit breaker is designed for fast selectivity
tripping. The selective contact system ensures the following:
●
Dynamic instantaneous short-circuit range
●
High breaking capacity
●
Selective protection response of the molded case circuit breakers in relation to each other
●
Selective protection response of the molded case circuit breakers in relation to other
protection devices (e.g. downstream low-voltage fuses)
Electronic trip unit (ETU)
The current sensor of the 3VA2 molded case circuit breaker comprises an iron-cored
transformer for the internal power supply and a Rogowski coil for precise current
measurement. Each transformer can be optimized accordingly for its specific task. Thanks to
the high accuracy of current measurement, the 3VA2 molded case circuit breaker is suitable
for power/energy measurement. In addition, finer adjustment of ground-fault current
monitoring is possible.
The electronic trip units (ETUs) provide the following protection functions:
●
Overload protection L ("L" = Long-time delay)
Adjustable in steps from 40% to 100% of the rated operational current of the molded case
circuit breaker.
●
Short-time delayed short-circuit protection S ("S" = Short-time delay) for time-selective
response in case of a short circuit
●
Instantaneous short-circuit protection I ("I" = instantaneous):
●
Protection of the neutral conductor against overload and short-circuit ("N" = neutral)
●
Protection against residual currents to ground ("G" = Ground fault)
Energy management and communication
The electronic trip units (ETUs) provide the following energy management and
communication functions:
●
Metering functions
●
Transfer of measured values and status information of the circuit breaker to a higher-level
communication network
●
Remote parameter assignment of tripping thresholds and circuit breaker parameters
●
Flexible, local digital inputs and outputs via the EFB300 external function box
●
Software commissioning support with the "powerconfig" software package
●
Testing and archiving with the TD300 and TD500 test devices (with powerconfig)