ProSoft Technology MVI56-101S - Manual (Page 53)

MVI56-101S ♦ ControlLogix Platform Configuring the MVI56-101S Module
IEC 60870-5-101 Slave Communication Module User Manual
ProSoft Technology, Inc. Page 53 of 193
August 2, 2011
2.4.4 Sequence Flag
In order to save bandwidth, you can configure the module to use the Sequence
Flag feature. If this feature is not selected, the module will send the Information
Object Address (IOA) and the data value for every Monitor information object in
a poll response to the Master. If this parameter is enabled, the module will turn
on the Sequence Flag bit in a Monitor response; send the Informaiton Object
Address of only the first object in the response, along with its data value; and
send only the data values for all the other information objects in the response.
The Master assumes that all other points use IOAs in a contiguous order (using
the first point as the starting reference address). Since the IOAs are omitted for
all but the first point, this feature allows each message packet to contain more
process data, which improves network throughput and optimizes bandwidth
utilization.
2.4.5 Parameter Offset
This parameter specifies the IOA (Information Object Address) offset to the
parameter data for the normalized parameter data. The value entered is added to
the Information Object address for the associated point to compute the
parameter IOA address.
The Master may send a "Parameter of Measured Normalized" or "Parameter of
Measured Scaled" command using the parameter IOA in order to change the
deadband values for specific points.
Note: The Low Limit and High Limit values are always calculated based on the deadband value as
described in the following table.
Point Value
Threshold Determined by the deadband set in the configuration file or altered by the write
command.
Low Last reported event value - threshold.
High Last reported event value + threshold.
For example, if the configuration sets two M_ME_NA points with IOA (Point #) of
600 and 601 and an M_ME_NA Parameter Offset value of 3000, it would result in
the parameter points shown in the table.