Distance test module is used to test all functions related to protection function IEEE number 21. It includes not only the tripping characteristic tests but also external scheme tests related to this protection function.

The module's functionality is distributed in the following sections:

Technical data: general parameters that affect all the tests contained in the Distance module, such as: Line data (line impedance, line angle, ground compensation factor), Impedance and Time Tolerance (both absolute and as a percentage), Transformer connection, and performance parameters of the specific distance relay mode
Distance Zones: Zones defined in the relay are listed grouped by single‐phase, phase‐to‐phase or three‐phase characteristics, which the user can activate, edit and adjust the operating time for each zone. Also, as standard key feature in ROOTS, the direct import of RIO files with relay characteristics and settings, reduces the data entry process to minor modifications. Graphical Characteristic Editor: ROOTS features an intuitive and powerful interactive graphical editor for geometrical definitions of protective characteristics and impedance zones. Lines and curves can be drawn in free hand mode and/or adjusted using numerical values and coordinates. The user can use MHO, Lens and Tomato characteristics shapes or create a customized characteristic as complex as desired. 

Graphical Characteristic Editor: ROOTS features an intuitive and powerful interactive graphical editor for geometrical definitions of protective characteristics and impedance zones. Lines and curves can be drawn in free hand mode and/or adjusted using numerical values and coordinates. The user can use MHO, Lens and Tomato characteristics shapes or create a customized characteristic as complex as desired.