Pilz PSS SB HYD, Basic license - Manual (Page 215)

Modular Block System: Hydraulic Presses 6-153
Safety guidelines for input parameters TOn and TOff
• The reaction time (input parameters TOn and TOff) must not adversely
affect the availability of the press.
• Please note that pressure and temperature fluctuations can vary the
valve's reaction times.
• Please note that the safety distance from the machine must be
calculated in accordance with the values established by measuring the
overrun on the press.
• Please note that the overrun of the machine will be determined by the
reaction time of the valve.
If the switching times of the valves increase during the lifetime of a
machine, the overrun distance will also increase. This means that the
safety distance will also need to be increased. Always check that the
reaction times are set correctly (input parameter
TOn and TOff). This is
the only way in which SB089 can sensibly monitor the reaction times on
which the safety distance is based, detect the increased reaction times
from the valve and therefore switch the valve to a safe condition (start
position).
• Reaction times should be set as short as possible (input parameter TOn
and TOff).
DANGER!
If the time values entered for TOn and TOff are too long, serious injuries
could result should the danger zone be accessed during operation.
The reaction time of the safety valve determines the stopping time of the
press on an emergency stop. The stopping time determines the safety
distance to the tool.
Reaction times should be included in the calculation of the safety
distance if the time values set for the parameters
TOn and TOff are
significantly higher than the actual valve reaction times.