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WL Circuit Breaker
WL Selection and Application Guide • 2005
Electronic Trip Unit
Basic Protective Functions ETU745 ETU748 ETU755 ETU776
Long-time overcurrent protection L ●●●●
Short-time delayed overcurrent protection S ●●●●
Instantaneous overcurrent protection I ● -- ●●
Neutral conductor protection N ●●●●
Ground fault protection G ❍❍❍❍
Additional Functions
Selectable neutral protection ●●●●
Defeatable short-time protection ● -- ●●
Defeatable instantaneous protection ● -- ●●
Selectable thermal memory ●●●●
Zone selective interlocking ●●●●
Selectable I
2
t or fixed short-time delay ●●●●
Adjustable instantaneous pick-up ●●●
Selectable I
2
t or I
4
t long-time delay ●●●●
Adjustable short-time delay and pick-up ●●●●
Selectable and adjustable neutral protection ●●●●
Dual protective setting capability -- -- ●●
Dynamic arc-flash sentry -- -- ●●
Extended instantaneous protection ●●●●
Parameterization and Displays
Parameterization by rotary switches (10 steps) ●●-- --
Parameterization by communication (absolute values) -- ●● ●
Parameterization by menu/keypad (absolute values) -- -- -- ●
Remote parameterization of the basic functions -- ●●
Remote parameterization of the additional functions -- ●●
Alphanumeric LCD ❍❍-- --
Graphical LCD -- -- -- ●
Metering Function
Metering function Plus ❍❍❍❍
Communication
CubicleBUS ●●●●
Communication via PROFIBUS-DP ❍❍❍❍
Communication via the MODBUS ❍❍❍❍
Communication via the Ethernet (BDA) ❍❍❍❍
● standard -- not available ❍ optional
For detailed information on the electronic trip unit functions see pages 1/36 thru 1/39
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