EUCHNER NXxxxAS1 - Handbuch (Seite 4)

Operating Instructions Safety Switches NX...AS
1
Correct use
EUCHNER safety switches series NX...AS1 are
operated as a slave on the safety bus
AS-Interface
Safety at Work and function as interlocking devices
without guard locking.
In combination with a safety guard, this safety
component prevents dangerous machine move-
ments from being performed for as long as the
safety guard is opened. A stop command is
triggered if the safety guard is opened during the
dangerous machine function.
For the control system, this means that
f starting commands which cause hazardous
situations must become active only when the
safety guard is in the protective position.
Before safety switches are used, a risk assessment
must be performed on the machine, e.g. in
accordance with
f EN ISO 13849, Safety of machinery - Safety-
related parts of control systems
f EN 12100-1, 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
programmable electronic control systems.
Correct use includes compliance with the relevant
requirements for installation and operation,
particularly
f EN ISO 13849, Safety of machinery - Safety-
related parts of control systems
f EN 1088, Safety of machinery. Interlocking
devices associated with guards. Principles for
design and selection
f EN 60 204-1, Electrical equipment of machines
Important:
f The user is responsible for the 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
EN ISO 13849-1:2008 is used for validation, the
Performance Level (PL) may be reduced if several
devices are connected one after the other.
f If a product data sheet is included with the
product, the information on the data sheet applies
in case of discrepancies with the operating
instructions.
Safety precautions
Safety switches fulfill a personal protection
function. Incorrect installation or tampering can
lead to severe injuries to personnel.
Safety components must not be bypassed
(bridging of contacts), turned away, removed
or otherwise rendered ineffective.
On this topic pay attention in particular to the
measures for reducing the possibility of bypassing
from EN 1088:1995+A2:2008, section 5.7.
The switching operation may only be triggered
by actuators specially provided for this
purpose which are permanently connected to
the protective guard.
A complete safety-oriented system generally
consists of several signaling devices, sensors,
evaluation units and concepts for safe
shutdown. The manufacturer of a machine or
installation is responsible for correct and safe
overall function.
All safety instructions and requirements stated
in the Operating Instructions of the AS-Inter-
face safety monitor used must be observed.
Mounting, electrical connection and setup only
by authorized personnel.
Function
EUCHNER safety switches series NX...AS1 permit
the safe monitoring of movable safety guards.
The position monitoring of the safety guard is
carried out with two positively driven contacts.
When the safety guard is closed, each NX...AS1
transmits a switch-specific, unique safety code
sequence with 8x4 bits via the AS-Interface bus.
This code sequence is evaluated by an AS-Inter-
face safety monitor. The first positively driven NC
contact is represented by the AS-Interface input
bits D0 and D1, while the second positively driven
NC contact is represented by D2 and D3.
The switch-specific safety code sequence is
transmitted via the AS-Interface input bits D0 to
D3 when the safety guard is closed.
When the safety guard is open, the values 0, 0, 0,
0 are transmitted in every bus cycle by D0 to D3.
The safety switch must be correspondingly
configured in the AS-Interface safety monitor (refer
to the operating instructions of the AS-Interface
safety monitor used and the status table).
Changing the actuating direction
Fig. 1: Changing the actuating direction
f Unscrew and open switch cover.
f Remove actuating head from the switch by turning
and refit in the required position (bayonet
fastening).
f Fit locking pins for protection against twisting
(Figure 2). It is then not possible to change the
actuating direction again.
Fig. 2: Fitting the locking pins and the slot cover
f Close the cover and screw in position.
f Cover the unused actuating slot with the enclosed
slot cover (Figure 2).
Mounting
Safety switches and actuators must not be
used as an end stop.
Mount the safety switch only in assembled
condition!
Increased overtravel of the actuator is not
possible with vertical approach direction.
Assemble the safety switch so that
f access to the switch is difficult for operating
personnel when the safety guard is open
f address programming, inspection and replace-
ment by authorized personnel is possible.
f Insert the actuator in the actuating head.
f Mount the safety switch positively.
f Permanently connect the actuator to the safety
guard so that it cannot be detached, e.g. using
the enclosed non-removable screws, rivets or
welding.
f Fit an additional stop for the movable part of the
safety guard.
Protection against environmental influences
A lasting and correct safety function requires that
the actuating head must be protected against the
penetration of foreign bodies such as swarf, sand,
blasting shot, etc.
Electrical connection
When choosing the insulation material and wire
for the connections, pay attention to the over-
temperature in the housing (depending on the
operating conditions)!
For use and operation as per the requirements of
(UL), an isolating transformer or a power
supply with secondary overcurrent protection (3 A)
must be used.
The safety switch is connected to the bus system
with a 2- or 4-pole connecting cable with M12 plug
connector via a passive AS-Interface distribution
box with a yellow AS-Interface cable.
Fig. 3: AS-Interface M12 plug connector terminal
assignment
Setup
f Setting the AS-Interface address
The address can be set prior to or after assembly.
The AS-Interface address of the safety switch is
set using an AS-Interface programming device.
Addresses 1 to 31 are valid.
The unit is programmed by connecting the
programming device to the M12 plug connector
on the safety switch with an AS-Inter face
programming device.
Default setting on delivery is the address 0. In
operation the AS-Interface LED
Fault illuminates
(only visible with cover removed)!
A
1 AS-Interface +
2 Not used
3 AS-Interface -
4 Not used
View of safety switch
plug connector
4 3
1 2