Safety Function

The remote I/O is equipped with safety-related analog inputs. The input values on the

inputs are safely transmitted to the connected controller via safeethernet. The outputs are

safely assigned their values by the connected controller via safeethernet.

Safety-Related Analog Inputs

The remote I/O is equipped with 8 analog inputs with transmitter supplies for the unipolar

measurement of voltages, referenced to L-.

The remote I/O is intended to measure the voltage on the inputs. To measure the current

on the inputs, connect a resistor of up to 500 Ω in parallel to each input.

Only shielded cables with a length of a maximum of 300 m must be connected to the

analog inputs. Each analog input must be connected to a twisted pair of wires. The

shielding must be connected to the remote I/O and the sensor housing and earthed of one

end to the remote I/O side to form a Faraday cage.

If an open-circuit occurs during voltage measurement (the line is not monitored), any input

signals are processed on the high-resistance inputs. The value resulting from this

fluctuating input voltage is not reliable; with voltage inputs, the channels must be terminated

with a 10 kΩ resistor. The internal resistance of the source must be taken into account.

For a current measurement with the shunt connected in parallel, the 10 kΩ resistor is not

required.

The analog inputs are designed to retain the metrological accuracy for 10 years. A

recalibration must be carried out every 10 years.