What are market-wide circuit breakers?
The index-based market-wide circuit breaker system applies at 3 stages of the index movement, either way viz. at 10%, 15%, and 20%.
These circuit breakers when triggered bring about a coordinated trading halt in all equity and equity derivative markets nationwide. The market-wide circuit breakers are triggered by movement of either the BSE Sensex or the Nifty 50, whichever is breached earlier.
Check out this page on NSE for more information.