Pilz PSS SB HYD, Basic license - Manual (Page 203)

Modular Block System: Hydraulic Presses 6-141
INFORMATION
Directional control valves may only be operated where the position of the
valve is monitored by acknowledging the valve's position within a
maximum reaction time.
VTyp = 0
TOn = KF 001 ... KF 350
TOff = KF 001 ... KF 350
Ensure you follow the guidelines given below under “Safety
guidelines for input parameters
TOn and TOff ”
• Registers an error when the valves are in the wrong position
• If an error occurs, the valves will be switched off immediately; it will not
be possible to reset the valves (reset lock).
• After an error, a reset will only be possible if the error has been rectified,
the valves are in their start position (valve de-energised,
acknowledgement from valve is present), the input parameter
Y1On = 1
and Y2On = 1, and no start signal is present (input parameter ON • 1).
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
valves' 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 parameters
TOn and TOff). This is
the only way in which SB088 can sensibly monitor the reaction times on
which the safety distance is based, detect the valves' increased reaction
times and therefore switch the valves to a safe condition (start position).
• Reaction times should be set as short as possible (input parameter TOn
and TOff).