BECKHOFF KL2521-0000 - Manual (Page 9)

Functional description
KL2521 7
Connection
Connection of the inputs
Circuit examples for output to A. The same principles apply to output B.
The optically isolated inputs are protected from overload by a current
limiter. The operating voltage can lie in the range between 5 V ... 24 V
DC
without any additional external circuitry. The GND connection is the
common ground for the two inputs, T and Z.
The circuit diagram shows the internal circuitry of the two inputs:
3 mA
konstant
GND Z,T
+T +Z
Connection of the outputs
Outputs A and B on the KL2521 can be used with different types of
connection. An integrated DC/DC converter supplies the outputs stage of
the two channels, A and B, with an electrically isolated 5 V power supply.
Connection to a RS485/RS232 receiver
The output can be operated as RS485 or as RS232 output. The circuit
generates the necessary differential signals.
KL2521-0000
+A
- A
Connection to an optocoupler (without external power supply)
The outputs can be used for direct connection of an optocoupler. The
output stage supplies the necessary output current using an internal 5 V
power supply.
220R
KL2521-0000
+A
- A