Digital inputs

The terminal provides the 24 VDC inputs (A, B, C, gate/latch). The function of these inputs can be found in chapter “Explanatory notes for parameters“ of the respective terminals.

EL1515, EL5151-0090, EL5152

EL5151-0021

The inputs are type 1 inputs according to EN 61131-2.

Digital input type 1, according to EN 61131-2

Voltage [V]

Input current [mA]

Signal voltage “0 - LOW”

-3 V … +5 V typ.

0 mA … 2.6 mA typ.

Signal voltage “1 - HIGH”

15 V … 30 V typ.

5 mA typ.

Digital inputs 1:
Characteristic input 24 VDC type1

Notice

Fast digital inputs – interference from interfering devices

Please note that the input wiring has very little filtering. It has been optimized for fast signal transmission from the input to the evaluation unit. In other words, rapid level changes/pulses in the µs range and/or high-frequency interference signals from devices (e.g. proportional valves, stepper motor or DC motor output stages) arrive at the evaluation unit almost unfiltered/unattenuated. These interferences can be incorrectly detected as a signal.

  • To suppress interference, an additional input filter can be parameterized.
  • Furthermore, EMC-compliant cabling and the use of separate power supply units for the terminal and the devices causing interference are recommended.