GRE170 has three models which differ according to the number of analog inputs and type of neutral current inputs.
The second digit of the model identifies input type for neutral current input. For example of model *0*, normal zero-phase current is input, and model *2* is equipped with a sensitive earth fault current input.
For each model, there are three different types which differ depending on the number of binary inputs and outputs. Combined 1A/5A current inputs and wide auxiliary supply ranges simplify type selection.
All models include multiple, high accuracy generator and motor protection elements such as overcurrent protection elements (for phase and/or earth fault) with inverse time and definite time delay functions, in accordance with the IEC 60255-151 standard, directional overcurrent protection, negative sequence overcurrent protection, voltage protection, motor status monitoring, locked rotor protection, number of starts limitation, start/stalled protection and thermal protection based on IEC 60255-8. Control functions such as two-step operation of circuit breakers are also provided.
Sensitive earth fault protection or current directional protection functions is available according to model type.