Rockwell Automation 1771-QDC, D17716.5.85(Passport) MNL. PLASTIC MOLDING MODULE - Manual (Page 9)

Preface
P-3
Command Blocks
Command blocks provide the parameters that control machine operation.
They are transferred from the PLC processor to the QDC module by means
of block transfer write (BTW) instructions in software ladder logic. Their
abbreviations are:
Acronym: Description:
MCC Module Configuration Block
JGC Jog Configuration Block
INC Injection Configuration Block
IPC Injection Profile Block
PKC Pack Configuration Block
HDC Hold Configuration Block
HPC Pack/Hold Profile Block
PRC PreĆdecompression Configuration Block
PLC Plastication Configuration Block
PPC Plastication Profile Block
PSC PostĆdecompression Configuration Block
DYC Dynamic Command Block
RLC Inject ERC  Values Command Block
Status Blocks
Status blocks report current status of molding-machine operation. They
are returned from the QDC module to the PLC processor by means of
block transfer read (BTR) instructions in software ladder logic. Their
abbreviations are:
Acronym: Description:
SYS System Status Block
IPS Injection Profile Status Block
HPS Pack/Hold Profile Status Block
PPS Plastication Profile Status Block
RLS Inject ERC  Values Status Block