ADLINK EOS-4000 - Manual (Page 38)

26 Introduction
It is recommended a resistance value be chosen allowing at
least 5 mA through the diode, assuming a maximum drop
across the diode of 0.5 V.
For example, for 24 V inputs a maximum resistance for Rs can
be found by the formula:
(24 V-0.5 V)/5 mA – 2.32kΩ = 2.38kΩ
DICOMn
DIn
2.32kŸ
DC12V~24V
EOS-4000