Undervoltage protection

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

Threshold values

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

• U_warn: If a supply voltage U_S or U_P falls below the upper threshold value U_warn, the bit "Warning Us" or "Warning Up" in the process data object "DPO Inputs Device" is set.
• U_err: If a supply voltage falls below the lower threshold value U_err, all outputs are switched off and the bit "Error Us" or "Error Up" in the process data object "DPO Inputs Device" is set.

The threshold values of the undervoltage protection cannot be adjusted.

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 variable
     „DPO Inputs Device“ > „Global Reset“.
• A voltage reset of U_S

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