This read-only value is the current-interval count of C-bit Errored Seconds, seconds during which at least one C-bit coding violation occurred, applicable only for DS3. It is the C-bit-framing equivalent of P-bit errored seconds, giving admins a per-second error view specific to that framing mode's overhead channel. For example, an admin investigating intermittent circuit complaints on a C-bit-framed DS3 checks csDs3StatCurrentCESs to see how many seconds in the current interval showed any C-bit error activity.