Connection Examples Of The Enabling Button - Bosch Rexroth VCH 08.1 Manual

DOK-SUPPL*-VCH*08.1***-PR02-EN-P
Rexroth IndraControl VCH 08.1 Hand-held Terminal

Connection Examples of the Enabling Button

Overview
At the IndraControl VCH 08.1 devices, the enabling buttons always
feature 2 circuits.
To meet the safety category 3 PL d in accordance with EN ISO 13849-1, the
enabling switch must be realized with 2 circuits and these circuits have to be
monitored on short circuits.
The safety category 3 PL d means, that 1 failure must not lead to the loss of
the safety function, and whenever possible, the single failure is detected. The
connection example in chapter "Connection Examples with PILZ PN0Z s6.1
Monitoring Device " on page 84
be fulfilled by the enabling button up to the output terminal K4 within the con‐
nection module. Observe that the entire concept of the machine must be laid
out according to the above mentioned principles.
The monitoring of the simultaneity by the monitoring device is necessary, be‐
cause otherwise maybe a failure culmination would not be recognised and this
would cause the safety loss.
Example:
If one channel of the enabling button switches to the enabled state as a result
of a failure and after some time the second channel also switches to the enabled
state as a result of an failure, then no de-energisation by the enabling button
would be possible.
Further the EN 60204-1 specifies that the enabling button is to be connected
to a category 0 stop or a category 1 stop, i.e. the energy must be switched off.
For calculating the PL for the "enabling" safety function the PL and B10d values
of all involved components have to be included. For details on the determination
of the PL for the whole safety function, please refer to EN ISO 13849-1 (chapter
6.3, and and appendix H and I).
Bosch Rexroth AG
Pin Assignments of the IndraControl VCH 08.1
shows how the safety category 3 PL d can
83/117