M241 and M258 frequency meters have a "Validity" output which is FALSE when no pulses are received after the duration defined in "Time base" parameter ( 10, 100 or 1000 ms).

When "Validity" output is FALSE, "CurrentValue" has the last computed frequency value (not 0), but this value must be ignored.

Đã phát hành cho: Schneider Electric Việt Nam