Protection selectivity — breaker coordination | GorkyCAD Pro
Selectivity coordinates breakers so a fault trips only the affected line, not the whole building. GorkyCAD Pro checks it automatically.
What is selectivity
A fault in one socket should trip only that group breaker, not the main breaker. Otherwise one socket cuts power to the whole house.
', 'Types of selectivity
Current selectivity — the rating difference between main and group breakers. Time selectivity — a trip delay on the upstream breaker. GorkyCAD Pro checks both.
- Current (by ratings)
- Time (by settings)
- Time-current curve check
Automatic check
When assembling the panel, GorkyCAD Pro compares the main breaker with group breakers and highlights pairs where selectivity is violated — with a fix suggestion.
', 'Why it matters
Without selectivity a single faulty socket can cut power to the whole building. Selectivity is reliability and safety of power supply.
']FAQ
What is checked?
Main breaker coordination with group breakers.
Which types?
Current and time selectivity.
Are there recommendations?
Yes, GorkyCAD Pro suggests how to fix a violation.
Frequently asked questions
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