July 2013 6.11 Monitoring functions 939
Repetition of the
power-up test
One of the requirements of EN ISO 13849-1 for the iTNC 530 HSCI is that the
power-up test (emergency-stop test and braking test) must be repeated within
no more than 168 hours. It must be ensured by the PLC program that this
requirement is met. However, a running NC program can be run to its end
even after the 168 hours have passed if the guard doors have been and remain
closed the entire time. However, this may only be done if the guard doors
remain closed until the power-up test has been repeated! If the guard doors
are open and the 168 hours have expired, the PLC program must trigger an
error with an emergency stop reaction. According to standards, once the 168
hours have passed it is no longer possible to rule out any faulty behavior of the
safety functions.
The emergency stop test can be started directly through the PLC module
9144. The braking test is started through the PLC module 9143. The required
timer for monitoring must be realized in the PLC program. When the control is
booted after the main switch is on, the control automatically runs the power-
up test.
The following PLC markers help you to realize the repeated power-up test:
M4189 – Emergency-stop test completed
The marker M4189 is set when the emergency-stop test of the control has
been completed. The marker is also reset during the execution of PLC
module 9144 and is not set again until the end of the emergency stop test.
M4190 – Emergency-stop test active
The marker M4190 is set when the control is ready for the emergency-stop
test after it has been started up. The marker remains set until the
emergency-stop test has been completed. During the execution of PLC
module 9144 the marker also remains set until the end of the emergency-
stop test.
M4191 – Control is ready
The marker M4191 contains the information of the "control-is-ready" output.
This information is given before the hardware output reaches the
corresponding physical status (MC.RDY or STO.A.G).
M4192 – Request for "Control Voltage ON"
The marker M4192 is set in controls without Functional Safety (FS) if there
is an NC software request for the control voltage to be switched on. You can
then automatically connect the machine control voltage again through a PLC
output and corresponding external circuitry.
Set Reset
M4189 Emergency stop test completed NC NC
M4190 Emergency stop test NC NC
M4191 Control is ready NC NC
M4192 Request for control voltage ON NC NC
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