ProSoft Technology PTQ-PDPMV1 - Manual (Page 216)

Hot Standby Support PTQ-PDPMV1 ♦ Quantum Platform
User Manual PROFIBUS DP Master Network Interface Module for Quantum
Page 216 of 306 ProSoft Technology, Inc.
August 12, 2014
The Watchdog Time, Delta Ttr and other parameters can only be edited by
selecting the User-Defined profile.
When the "Hot Standby System" checkbox is marked, the PCB Master
configuration tool follows the rules below:
Parameter Calculation
Ttr is to be doubled in order to support one "passive" and one "active" Hot
Standby Master on the same network. Note that the Watchdog value also must
be recalculated because of the doubled Ttr.
To allow a switchover the Watchdog value that is calculated from the Ttr must be
increased. Two new parameters are introduced: HsbyWatchdogFactor and Host
Delay Time. The watchdog is calculated according to the following equation:
Watchdog = (Calculated watchdog * HsbyWatchdogFactor) + Host Delay Time
The HsbyWatchdogFactor for different baud rates is defined in the following
table:
Baud Rate XML Keyword Value
9.6 kBaud HsbyWdFactor_9_6k 1
19.2 kBaud HsbyWdFactor_19_2k 1
45.45 kBaud HsbyWdFactor_45_45k 1
93.75 kBaud HsbyWdFactor_93_75k 1
187.5 kBaud HsbyWdFactor_187_5k 1
500 kBaud HsbyWdFactor_500k 1
1.5 MBaud HsbyWdFactor_1_5M 2
3 MBaud HsbyWdFactor_3M 2
6 MBaud HsbyWdFactor_6M 2
12 MBaud HsbyWdFactor_12M 2
The Host Delay Time is set to 300 ms in the PCB Master configuration.
Invalid Master addresses:
1 The Master address must not equal 0.
2 The Master address must not equal any assigned slave address + 1.
Invalid Slave addresses:
1 A slave address must not equal the assigned Master address - 1.