Forced Checking Procedure - Siemens SINUMERIK 840D sl Function Manual

Safety Functions Integrated in the Drive
4.1 General information about SINAMICS Safety Integrated
4.1.4

Forced checking procedure

Forced checking procedure and test of the shutdown paths
The forced checking procedure function at the switch–off signal paths is used to
detect software/hardware faults at both monitoring channels in time and is auto-
mated by means of activation/deactivation of the "Safe Torque Off" function.
To fulfill the requirements of EN 954–1 regarding timely error detection, the two
shutdown paths must be tested at least once within a defined time to ensure that
they are functioning properly. For this purpose, the forced checking procedure
must be either initiated manually by the user or automatically as part of the pro-
cess.
A timer ensures that the forced checking procedure is carried out as quickly as
possible.
S p9659
The forced checking procedure of the shutdown paths must be carried out at least
once during the time set in this parameter.
After this time has expired, an appropriate alarm is issued (A01699 "SI CU: The
shutdown paths must be tested") and remains until the forced checking procedure
has been performed.
The timer is reset to the selected value each time the STO function is deactivated.
When the appropriate safety devices are implemented (e.g. protective doors), it
can be assumed that running machinery will not pose any risk to personnel. For
this reason, only an alarm is output to inform the user that a forced checking pro-
cedure is due and request that this be carried out at the next available opportunity.
This alarm does not affect machine operation.
The user must set the time interval for carrying out the forced checking procedure
to between 0.00 and 9000.00 hours depending on the application (factory setting:
8.00 hours).
The 9000 hours are only applicable for STO, SBC, SS1 functions that are integra-
ted in the drive and controlled via local terminals.
When using the safety–related motion monitoring functions according to Chapter 6,
the value should be set to 9000 hours so that the alarm to carry out the forced
checking procedure is no longer output. After carrying out the forced checking pro-
cedure from STO, the forced checking procedure timer is also re–started by the
motion monitoring functions.
Examples for carrying out the forced checking procedure:
S When the drives are at a standstill after the system has been powered–up.
S When the protective door is opened.
S In defined cycles (e.g. every 8 hours).
S In the automatic mode (time and event dependent).
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SINUMERIK 840D sl/SINAMICS S120 SINUMERIK Safety Integrated (FBSI sl) – 05.2008 Edition
SI timer for the forced checking procedure
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05.08