6
Operating Instructions
Safety Switches TZ…
Correct use
Safety switches series TZ are interlocking devices
with guard locking (separate actuator). The actu‑
ator has a low coding level. In combination with a
safety guard and the machine control, this safety
component prevents the safety guard from being
opened while a dangerous machine function is
being performed.
This means:
f
Starting commands that cause a dangerous ma‑
chine function must become active only when the
safety guard is closed and locked.
f
The guard locking device must not be unlocked
until the dangerous machine function has ended.
f
In applications for the protection of people, the
position of the guard locking must be monitored by
evaluating the contact for the solenoid monitoring
in the safety circuit.
f
Closing and locking a safety guard must not cause
automatic starting of a dangerous machine func‑
tion. A separate start command must be issued.
For exceptions, refer to EN ISO 12100 or relevant
C‑standards.
Devices from this series are also suitable for process
protection.
Before the device is used, a risk assessment must
be performed on the machine, e.g. in accordance
with the following standards:
f
EN ISO 13849‑1, Safety of machinery. Safety re‑
lated parts of control systems. General principles
for design
f
EN ISO 12100, Safety of machinery ‑ General
principles for design ‑ Risk assessment and risk
reduction
f
IEC 62061, Safety of machinery. Functional safety
of safety‑related electrical, electronic and program‑
mable electronic control systems.
Correct use includes observing the relevant require‑
ments for installation and operation, particularly
based on the following standards:
f
EN ISO 13849‑1, Safety of machinery. Safety re‑
lated parts of control systems. General principles
for design
f
EN ISO 14119, Safety of machinery. Interlocking
devices associated with guards. Principles for
design and selection
f
EN 60204‑1, Safety of machinery. Electrical
equipment of machines. General requirements.
Important!
f
The user is responsible for the correct integration
of the device in a safe overall system. For this
purpose, the overall system must be validated,
e.g. in accordance with EN ISO 13849‑2.
f
If the simplified method according to Section 6.3
of EN ISO 13849‑1:2015 is used for determining
the Performance Level (PL), the PL might be re‑
duced if several devices are connected in series.
f
Logical series connection of safe contacts is
possible up to PL d in certain circumstances.
More information about this is available in
ISO TR 24119.
f
If a product data sheet is included with the prod‑
uct, the information on the data sheet applies
in case of discrepancies with the operating
instructions.
Safety precautions
WARNING
Danger to life due to improper installation or due
to bypassing (tampering). Safety components
perform a personal protection function.
f
Safety components must not be bypassed,
turned away, removed or otherwise rendered
ineffective. On this topic pay attention in partic‑
ular to the measures for reducing the possibility
of bypassing according to EN ISO 14119:2013,
Sec. 7.
f
The switching operation must be triggered only
by actuators designated for this purpose.
f
Prevent bypassing by means of replacement
actuators. For this purpose, restrict access to
actuators and to keys for releases, for example.
f
Mounting, electrical connection and setup only
by authorized personnel possessing special
knowledge about handling safety components.
CAUTION
Danger due to high housing temperature.
f
Protect switch against touching by personnel or
contact with inflammable material.
Function
The safety switch permits the locking of movable
safety guards.
In the switch there is a rotating switching disc and a
locking arm that block/release the guard locking pin.
The guard locking pin is moved on the insertion/
removal of the actuator and on the activation/
release of the guard locking. During this process
the switching contacts are actuated.
If the guard locking pin is blocked (guard locking
active), the actuator cannot be pulled out of the
switch head. For design reasons, guard locking can
be activated only when the safety guard is closed
(failsafe locking mechanism).
Position monitoring of the safety guard and monitor‑
ing of interlocking are performed via two separate
switching elements.
SK
ÜK
1 2 3 4 5 6
GN
RD
Figure 1: Function of safety switch TZ
The safety switch is designed so that fault ex‑
clusions for internal faults in accordance with
EN ISO 13849‑2:2012, Table A4, can be assumed.
Guard lock monitoring
All versions feature at least one safe contact for
monitoring guard locking. The contacts are
opened when guard locking is released.
Door monitoring contact
All versions additionally feature at least one door
monitoring contact. Depending on the switching
element, the door monitoring contacts can be
either positively driven (contacts ) or not posi‑
tively driven.
The door monitoring contacts are actuated when
the safety guard is opened.
Version TZ1
(Guard locking actuated by spring force and released
by energy ON)
f
Activating guard locking: close safety guard; no
voltage at the solenoid
f
Releasing guard locking: apply voltage to the solenoid
The spring‑operated guard locking functions in
accordance with the closed‑circuit current princi‑
ple. If voltage is interrupted at the solenoid, guard
locking remains active and the safety guard cannot
be opened directly.
If the safety guard is open when the power supply
is interrupted and the guard is then closed, guard
locking is activated. This can lead to persons being
locked in unintentionally.
Version TZ2
(Guard locking actuated by energy ON and released
by spring force)
Important!
Use as guard locking for personnel protec‑
tion is possible only in special cases, after
strict assessment of the accident risk (see
EN ISO 14119:2013, Section 5.7.1)!
f
Activating guard locking: apply voltage to the
solenoid
f
Releasing guard locking: disconnect voltage from
the solenoid
The magnetically actuated guard locking operates
in accordance with the open‑circuit current principle.
If the voltage at the solenoid is interrupted, the
guard locking is released and the safety guard can
be opened directly!
Switching states
The detailed switching states for your switch can be
found in Figure 5. All available switching elements
are described there.
Safety guard open
The safety contacts and are open.
Safety guard closed and not locked
The safety contacts are closed. The safety
contacts are open.
Safety guard closed and locked
The safety contacts and are closed.
Selection of the actuator
NOTICE
Damage to the device due to unsuitable actuator.
Make sure to select the correct actuator.
Additionally pay attention to the door radius and
the fastening options (see Figure 6).
Manual release
Some situations require guard locking to be released
manually (e.g. malfunctions or an emergency). A
function test should be performed after release.
More information on this topic can be found in the
standard EN ISO 14119:2013, Section 5.7.5.1. The
device can feature the following release functions:
Mechanical release
In the event of malfunctions, the guard locking can
be released with the mechanical release irrespective
of the state of the solenoid.
The contacts are opened when the mechanical
release is actuated. A stop command must be
generated with these contacts.
Actuating mechanical release
1. Remove key from sealing wire.
2. Remove locking screw.
3. Release by turning the key.
¨
¨
Guard locking is released.
Important!
f
The actuator must not be under tensile stress
during manual release.
f
After use, reset the mechanical release and
screw in the locking screw and restore sealing
using a new seal.
