Emergency Stop Applications
Pilz GmbH & Co. KG, Felix-Wankel-Straße 2, 73760 Ostfildern, Germany, Telephone: +49 711 3409-0, Telefax: +49 711 3409-133, E-Mail: [email protected]
2011-10
2.1-15
2.1
Safety assessment
The safety relays PNOZ s5 (K2), PNOZ s9
(K3) and contactors KM3, KM4, KM5 and
KM6 must be installed in a single
mounting area (control cabinet) in order
to exclude a short across the output.
Earth faults and shorts between contacts
in the input circuit are detected.
A fault on the device does not lead to the
loss of the safety function.
The safety relays PNOZ s5 (K2) and
PNOZ s9 (K3) can be started when the
input circuit at K2 is closed first, followed
by reset button S4. This avoids an
unwanted reset before the input circuit is
closed or as a result of the reset button
being overridden.
The delay time set for the safety relay
PNOZ s5 (K2) must be longer than the
maximum braking time on the drive
regulator A2. The delay time set for the
safety relay PNOZ s9 (K3) must be longer
than the maximum braking time on the
drive regulator A3.
The time delay must not be able to cause
an additional hazard.
If the position of the operating mode
selector switch (mode) at K2 or the rotary
switch for the time setting is changed
during operation, an error message will
be triggered; the safety contacts on K2
and K3 open. This fault condition can
only be rectified by switching the supply
voltage on the safety relay PNOZ s5 (K2)
off and then on again.
PL e of EN ISO 13849-1, SIL 3 of EN 62061
PNOZ s5 - Safe standstill of two drives
If the position of the operating mode
selector switch (mode) at K3 or the rotary
switch for the time settings is changed
during operation, an error message will
be triggered; the safety contacts on K3
open. This fault condition can only be
rectified by switching the supply voltage
on the safety relay PNOZ s9 (K3) off and
then on again.
