Notes On The Protective Circuit Of External Relays/Contactors (Freewheeling Circuit) - Bosch Rexroth IndraControl S20 Manual

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Connection examples for safe outputs
7.2 Notes on the protective circuit of external
relays/contactors (freewheeling circuit)
IndraControl S20 Module With Safe Digital Outputs S20-PSDO-8/3
The following are specified for each example:
• Basic specifications
The table specifies the main data for the example.
• Device diagnostics and behavior of the module in the event of an error
Diagnostic capability depends on the parameterization.
If a message is transmitted to the controller in the event of an error, the mes-
sage is specified in the tables. Information on the relevant error code as well
as possible solutions and information as to whether the error message must
be acknowledged: see
• Typical parameterization
The table illustrates an example of all the parameters for the specified assign-
ment.
Key for tables in this chapter:
Representation Meaning
Bold Mandatory setting
Normal Typical setting, another setting is possible depending on the
application
– Not evaluated
Fig. 7-1 Parameterization tables
Errors (cross-circuits, short circuits) which can be prevented by correct installation
(e.g., protected cable installation, isolated cable installation, double insulation, use
of ferrules) are not described in the tables.
Only errors between outputs, which are on the same connector, are described. For
example, in the event of correct installation, cross-circuits with outputs of other
connectors cannot occur.
K1
69400021
Fig. 7-2 Example of the freewheeling circuit for an external relay
Observe the following measures:
• Limit the voltage induced on circuit interruption to < –15 V (e.g., with RC ele-
ments, suppressor diodes or varistors).
• Please note that the freewheeling circuit affects the fall time and the service life
of the contactor.
• Please observe the specifications of the relay manufacturer when dimension-
ing the relay protective circuit.
DOK-CONTRL-S20*PSDO*8*-AP02-EN-P
"Errors: messages and removal" on page 43.