Beckhoff EL28 Series, Документация

Страница: 54 / 160

Basics communication
EL28xx-xxxx 54 Version: 2.2
Fig. 33: EtherCAT tab -> Advanced Settings -> Behavior -> Watchdog
Notes:
• the multiplier is valid for both watchdogs.
• each watchdog has its own timer setting, the outcome of this in summary with the multiplier is a
resulting time.
• Important: the multiplier/timer setting is only loaded into the slave at the start up, if the checkbox is
activated.
If the checkbox is not activated, nothing is downloaded and the ESC settings remain unchanged.
Multiplier
Multiplier
Both watchdogs receive their pulses from the local terminal cycle, divided by the watchdog multiplier:
1/25 MHz * (watchdog mult 2) = 100 µs (for default setting of 2498 for the multiplier)
The standard setting of 1000 for the SM watchdog corresponds to a release time of 100 ms.
The value in mult 2 corresponds to the number of basic 40 ns ticks representing a watchdog tick.
The multiplier can be modified in order to adjust the watchdog time over a larger range.