State LEDs

LED State Color OFF ON Flashing
DO0 to DO15 Digital output Yellow Output is OFF Output is ON (the input voltage is even displayed if the supply voltage is OFF)
DC16 to DC23 Digital input/output Yellow Input/output is OFF Input/output is ON (the input voltage is even displayed if the supply voltage is OFF)
AI0 to AI3 Analog input Yellow Input is OFF Input is ON (brightness depends on the value of the analog signal)
AO0 to AO1 Analog output Yellow Output is OFF Output is ON (brightness depends on the value of the analog signal)
UP Process supply voltage 24 VDC via terminal Green Process supply voltage is missing Process supply voltage OK
CH-ERR1 Channel error, error messages in groups (digital inputs/outputs combined into the groups 1, 2, 3, 4) Red No error or process supply voltage is missing Severe error within the corresponding group Severe error within the corresponding group (e.g. short circuit at an output)
CH-ERR2 Red
CH-ERR3 Red
CH-ERR4 Red
CH-ERR *) Module error Red Internal error
*) All of the LEDs CH-ERR1, CH-ERR2 to CH-ERR4 light up together