Specifications

IP 240 Operation
5.3 Matching to Encoder Signals
Encoders with 24 V DC signals and encoders which generate signals to the RS 422 A or a similar
standard can be connected to the inputs of the IP 240. The user can set coding switches for
matching the IP 240 to the encoder signals.
5.3.1 Settings for Symmetrical or Asymmetrical Signals
All incremental encoders whose outputs comply with the RS 422 A standard supply symmetrical
signals A, B and Z and their inverted signals. These encoders have line drivers at the outputs, e.g.
26LS31, 75172 or 75174.
All incremental encoders whose outputs produce a 24 V DC level supply asymmetrical signals A*,
B* and Z*. These encoders have stages which switch to P potential at the outputs or open
collector outputs connected to 24 V via external pull-up resistors.
Fig. 3-6. Setting Switchbank S4 for Symmetrical or Asymmetrical Signals
Switchbank S4
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Channel 1
on
off
Channel 2
On: Asymmetrical signals A*, B*, Z*
Off: Symmetrical signals A/ A, B/B, Z/Z
5.3.2 Settings for Encoder Signal Levels
Input signals A*/CLK, B*/GT, Z* and IN must be set to 24 V DC on switchbank S5 for channel 1
and on switchbank S6 for channel 2.
Warning
A 5 V DC level setting is not permissible at the present time for reasons of noise
immunity. All switches on the switchbank must be set to ”on”.
Fig. 5-7. Setting the Encoder Signal Level on Switchbanks S5 and S6
On: 24 V DC input level
Off: not permissible
Switchbank S5 (S6)
A*/CLK
B*/GT
Z*
IN
21
on
off
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EWA 4NEB 811 6120-02 5-7