As part of these studies, we consider equipment damage curves, transformer inrush, minimum and maximum site fault levels. Site specific philosophies and distribution network requirements are taken into account when creating relay grading curves. Typically most sites require coordination with the upstream distribution settings.
Settings can be provided for the following types of protective device:
- Unrestricted overcurrent and earth fault (non-directional)
- G59/2 loss of mains
- Transformer Differential and Restricted Earth Fault
- Cable Differential
- Neutral Voltage Displacement
- Distance protection
- Negative phase sequence
- Directional overcurrent and earth fault protection.
TNEI can also provide assistance with the specification of protection current transformers and provide a review of existing protection schemes.
For more information on our power system protection coordination studies, please get in touch.