1. EP9224-0037 - Power distribution for EtherCAT Box Modules
2. Commissioning and configuration
3. Protective functions
4. Undervoltage protection

Undervoltage protection

The undervoltage protection prevents connected EtherCAT P devices from being operated with a supply voltage that is too low. A malfunction of the EtherCAT P devices due to undervoltage is thus impossible.

The undervoltage protection has two threshold values, see Technical data:

• U_warn: A warning message is output if a supply voltage U_S or U_P falls below the upper threshold value U_warn.
• U_err: If a supply voltage falls below the lower threshold value U_err, all outputs are switched off and an error message is output.

The threshold values of the undervoltage protection cannot be parameterized.

Deactivation for U_p

The undervoltage protection for the peripheral voltage U_P can be deactivated in the CoE index F80E:05 "Disable Up Undervoltage Error". That is useful in applications in which U_P is not needed. In such applications U_P would otherwise only have to be connected so as not to trigger the undervoltage protection.

If the output voltages have been switched off by the undervoltage protection, they can be re-activated in two ways:

• a positive edge on the output variables
     „DPO Inputs Device“ > „Global Reset“.
• A voltage reset (U_S)

Requirement: Both supply voltages are higher at this point in time than the upper threshold value U_warn.