
Substation Grounding Program
The CYMGRD software is a substation grounding grid design and analysis program specially designed to help engineers optimize the design of new grids and reinforce existing grids, of any shape, by virtue of easy to use, built-in danger point evaluation facilities.
User-friendly data entry, efficient analysis algorithms and powerful graphical facilities render the CYMGRD software an efficient tool that helps the engineer arrive at technically sound and economical designs.
The use of the CYMGRD software allows for the rapid analysis of various design alternatives to choose an economical solution for any particular installation.
The program conforms to IEEE 80™ 2000, IEEE 81™ 1983 and IEEE 837™ 2002.
• Computation of the reduction factor (Cs) as per IEEE 80™ 2013 and IEC 60 479™

Analytical Capabilities
- Finite element analysis of the ground grid conductors, rods and wire assembly
- Computation of Rg and GPR (Ground Potential Rise)
- Touch and surface potential analysis, inside and outside the grid perimeter, with color display in 2D or 3D representation
- Step voltage analysis
- Uniform or two-layer soil model from field measurements or user-defined values
- Computation of reduction factor (Cs)
- Library of the most common types of surface layer materials
- Library of typical station soil resistivity values
- Safety assessment calculations for maximum permissible touch and step voltages as per IEEE 80™ 2000
- Current Split Factor (SF) estimated from substation configuration data as per IEEE 80™ 2000
- Computation of the Decrement Factor (DF) from bus (X/R) ratio and shock duration data as per IEEE 80™ 2000
- DC component of asymmetrical fault current taken into account in the computations
- Electrode analysis for the optimal sizing of conductors and rods based on the most common type of electrode material as per IEEE Std. 80-2000 and Std. 837-2002
- Supports symmetrical or asymmetrical grids of any shape
- Arbitrarily located ground rods
- Ability to model return electrodes and distinct electrodes
- Ability to model concrete encased rods
- Computation of maximum single phase to ground fault current for a specified grid
• Safety assessment calculations for maximum permissible touch and step voltages as per IEEE 80™ 2013, IEC 60 479™, EN 50522™ 2010, BS™ 7354-1990, EA-TS™41-24-1992 and CENELEC™ HD 637 S1-1999
• Current Split Factor (SF) estimated from substation configuration data as per IEEE 80™ 2013
• Computation of the Decrement Factor (DF) from bus X/R ratio and shock duration data as per IEEE 80™ 2013
• DC component of asymmetrical fault current considered in the computation
• Electrode analysis for the optimal sizing of conductors and rods based on the most common type of electrode material as per IEEE 80™ 2013 and IEEE 837™ 2002
• Supports symmetrical or asymmetrical grids of any shape• Arbitrarily located ground rods
• Ability to model return and distinct electrodes
• Ability to model material encased rods and conductors.
• Computation of maximum allowable single phase to ground fault current for a specified grid.