www.ssz-gmbh.de [email protected] Thüringerstrasse 17, 46286 Dorsten
14
The applied prevention measures against systematic defects
(EN ISO 13849-1: 2015))
•
The design of the devices ensures protection in case of sup-
ply voltage loss. The output relays become disconnected,
i.e., the electric circuit in open on the output relay contacts.
•
In the supplying branches of measurement circuits, integrated,
voltage stabilisers are applied which, together with capacitive
filters, considerably protect against input voltage variations.
•
The input resistive measurement system has been designed
to eliminate as much as possible errors, resulting from un-
stable supply voltage.
•
The applied output relays, designed for use in safety devices,
are subject of internal control.
•
The design configuration of SSZ safety units has for years
been used in thousands of applications and is also used in
other, manufactured by us devices.
•
Control units: SSZ-RZ4 and SSZ-RZ4B: have been designed
in line with the EU’s engineering pattern and checked and
approved with regards to electromagnetic compatibility,
ventilation, cooling and vibrations.
•
The SSZ-GmbH Company has for more than 25 years been
carrying out internal quality control in its full scope, i.e.,
including particular elements and their documentation.
•
The same team of qualified employees participates in the
production process.
•
The parts and components in the devices originate from prov-
en, recognised manufacturers with appropriate certificates.
•
The Company enjoys a more than 25-year tradition and
experience, represented all over the world, while in some
European countries, SSZ products are market leaders.
Acceptance procedure
1.Pressure-sensitive device assembly and functionality check
acc. to the requirements in the Operation Manual of the chosen
SSZ pressure sensitive device .
2.Checking for correct cabling from the control unit to the SSZ
pressure sensitive device; a particular attention shall be paid to
redundancy preservation in the system!
3.Checking of the safety function– acc. to the safety documen-
tation.
4.Measurement of the entire system’s response time and “full
time stop”, as well as functionality(lock or release) check, caused
by the activation of an SSZ pressure-sensitive device. The results
should be compared to the specification requirements. All results
should be written into the documentation of the machine.
5.A special attention shall be paid to the signalling system in the
SSZ control unit (one red and two green LEDs), indicating either
normal operation or failure of the system!
If none of the LEDs is active, the supply of the control unit should
be checked. If the supply connection to the control unit is cor-
rect, while its functionality still fails, it is necessary to contact
the manufacturer.
The same acceptance procedure shall be valid when particular,
individual components are replaced (either of SSZ pressure-sen-
sitive device or a replacement of the SSZ control unit)
The installer shall be obliged to fill in an identification form of
an installed device. In order to ensure a correct identification,
please enter in the form, the number from the hologram on the
pressure-sensitive device and on the SSZ control unit.
The system does not have an auto-check
function. According to the level of safety
assurance- PLd , the system in the standby
mode is controlled by the unit.
