User manual
PTQ-PDPMV1 ♦ Quantum Platform  Hot Standby Support 
PROFIBUS DP Master Network Interface Module for Quantum  User Manual 
ProSoft Technology, Inc.  Page 201 of 306 
August 12, 2014 
7.3  PTQ-PDPMV1 Operation 
While in Primary mode, the module will read the output area and write the input 
area. The module will constantly scan the HSBY control word to determine the 
HSBY state. 
  Active LED will flash if the module is in Standby mode in a Hot Standby 
system. The Hot Standby Status Word of the Modicon Quantum processor is 
read during each end-of-scan. 
  During switchover caused by a failure on the primary, all PROFIBUS I/Os will 
be held at their last values, until the moment the new PTQ takes control (no 
glitch on I/O devices). 
7.3.1  PTQ-PDPMV1 HSBY Diagnostic Data 
PTQ Input Data Block 
The PTQ module reports the HSBY Local and Remote Status Registers via the 
Input Data Block. 
Input Data Block (HSBY words only) 










