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:
- Uwarn: A warning message is output if a supply voltage US or UP falls below the upper threshold value Uwarn.
- Uerr: If a supply voltage falls below the lower threshold value Uerr, all outputs are switched off and an error message is output.
The threshold values of the undervoltage protection cannot be parameterized.
Disabling for Up
The undervoltage protection for the peripheral voltage UP can be disabled in the CoE index F80E:05 "Disable Up Undervoltage Error". That is useful in applications in which UP is not needed. In such applications UP would otherwise only have to be connected so as not to trigger the undervoltage protection.
Resetting an error state
If the output voltages have been switched off by the undervoltage protection, they can be re-activated in two ways:
- a positive edge at the output variable
"DPO Inputs Device" > "Global Reset". - A voltage reset (US)
Requirement: Both supply voltages are higher at this point in time than the upper threshold value Uwarn.