ProSoft Technology MVI56-101S - Manual (Page 46)

Configuring the MVI56-101S Module MVI56-101S ♦ ControlLogix Platform
User Manual IEC 60870-5-101 Slave Communication Module
Page 46 of 193 ProSoft Technology, Inc.
August 2, 2011
2.3.22 IV Check Delay Time
1 to 65535 seconds, or 0 to disable Invalid Bit Monitoring
This parameter sets the number of seconds between IV Bit value checks. Every
IEC database Monitor information object which has an IV Bit address set greater
than 0 will have that bit address checked at the interval specified by this
parameter.
Setting this parameter to zero (0) will disable data validity checking.
2.3.23 IV Fail Count
1 to 65535 seconds, or 0 to disable Invalid Bit Monitoring
This parameter sets the number of successive IV Bit check failures which must
occur before the data from an IEC database Monitor information object will be
reported to the remote Client as invalid data.
An IV Bit Check Failure occurs when the IV Bit value in the module database is
set ON {when it contains a value of one (1)} at the time an IV Bit Check is
performed. IV Bit Check failures are counted and held in separate IV Bit Check
Failure accumulators for each IEC Monitor information object configured for
validity checking. If the value in any information object's failure accumulator
becomes equal to the value set in this IV Fail Count parameter, the module will
consider data from this information object invalid and report its invalid status to
the Client, along with its data value.
Setting this parameter to zero (0) will disable data validity checking.
2.3.24 Event Scan Delay
1 to 65535 milliseconds, or 0 to disable
If set to 0, the feature will be disabled and the module will not generate any
events. If set from 1 to 65535, the parameter represents the number of
milliseconds between event scanning. This parameter defines how often the
program will scan for new events in the databases.
NOTE: The lower you set this value, the more negative effect it will have on overall module data
update and transfer performance. Scanning for new events causes an interrupt of other data
manipulation functions. The more often these scan interrupts occur, the less processor time the
module will have available for other data operations. When choosing a value for this parameter,
you should consider such factors as how often events might be generated by your application and
how often you need to recognize and respond to such events. This will allow you to set this value
as high as it can be set and still maintain your overall event capturing and reporting strategy.
Doing so can reduce the amount of interrupts, prevent excessive event scanning, and maximize
data update and transmission rates.