21 Terms and Abbreviations
05.91
PIQ
Abbreviation for process output image (see Section 1)
PLC
Programmable logic control, the interface control of the
SINUMERIK to the machine in question (see Section 1,
General Overview)
PLC user program
Program for the PLC which adapts the SINUMERIK
880 to the machine concerned. It is compiled by the user
(= machine manufacturer); see Section 1. Programming
languages: Step 5 (in various forms of representation) or
a high-level language of the HLL interface (see "PLC 135
WB Planning Guide", "HLL Programming", own
documentation)
Power Off
Switching off the NC, especially power failure
Power On
Switching on the NC, especially return of supply after a
power failure
PP
Abbreviation for part program
PRESET
NC mode
Process alarm byte
Alarm byte
Process image
Depiction of the machine signals in the bit-serial
addressable I/O area (see Section 1)
PW
Abbreviation for peripheral word
QB
Output byte, byte in output area, in which output
signals are depicted. Can be addressed bit by bit (see
Section 1).
QW
Output word, 2 consecutive QBs, starting at an even
address
R parameter
Parameter (variable) in the part program
RAM
Random access memory from which data can be read
and into which data can be written
Rapid (traverse) override
Change of feedrate specified for rapid traverse
Rapid traverse
Accelerated travel movement of an axis
REF
NC mode
Reference point
Reference point on the machine for the measuring system
21–8
© Siemens AG 1991 All Rights Reserved 6ZB5 410-0HE02
SINUMERIK 880 (PJ)