Assignment of input and output parameters, Minimum scan time, Mbs basics – Pilz PSS SB NOT, Basic license User Manual

Page 40

Advertising
background image

5-12

MBS Basics

Modular Block System: Emergency Stop Circuits

Assignment of input and output parameters

Input and output parameters should be assigned in accordance with the
details given in the operating manual.

WARNING!
If several unused output parameters are connected to the same flag,
malfunctions may occur in the standard function blocks. If an unused
output has to be assigned a flag, make sure the output is assigned to a
flag that is not used anywhere else in the program.

Minimum scan time

Most of the timer functions required within the blocks are performed using
cycle counters. This means that almost all the timers are available for use
in applications.

INFORMATION

• If MBS blocks are used, a minimum scan time must always be

entered in the configurator. Empirical values should be used.

• If the error message F-20/06 (error category/error number) appears in

the CPU display, you must amend the minimum scan time appropriately.
This error message indicates that the minimum scan time has been
exceeded. The PSS must not be operated while this error message is
present.

SB070 and SB071 automatically enter the minimum scan time in DW1022
of the administration data blocks. In this way it is automatically available to
the MBS.

INFORMATION
Please note that the times are imprecise. The lack of precision on times is
due to the cyclical processing of the user program. It is determined by the
scan time of the respective user program.
The following is generally valid:
The greater the ratio of time value to scan time, the greater accuracy you
will have with the required times.

Advertising