ProSoft Technology MVI71-DNP - Manual (Page 95)

Reference MVI71-DNP ♦ PLC Platform
DNP 3.0 Master/Slave Communication Module
ProSoft Technology, Inc. Page 95 of 172
August 23, 2007
Mode DNP Feature Discussion
Slave Will events be
logged before time
synchronization has
occurred? This feature will avoid logging events without the proper date
and time stamping. When the DNP slave driver is initialized, it
will have the IIN bit set to request time synchronization from the
remote master unit. The master must synchronize the time
before the module will generate events. This feature is selected
using bit 8 in the module's configuration word.
Slave Will unsolicited
messages be used?
If so, how may for
each class before
triggering and what
is the delay time? Unsolicited messaging provides the means for a slave unit to
send event data asynchronously to the master unit without a
request from the master. This requires the use of collision
avoidance to prevent two or more units from transmitting data
on the network at one time.
Slave Will the module use
the secondary DNP
Slave port? The secondary DNP slave port on the module is a backup port
to the primary slave port. Only one port can be used at any one
time. The module supports automatic switching between the
two ports based on several factors.
Master Will the module use
the DNP Master
port? The module can be configured as a DNP master unit to
interface with DNP slave (IED) units. This feature requires
configuration of the communication characteristics for each
slave and the definition of a command list. The command list
polls the slave units and to map the data from the IED units to
the databases contained in the module.
Master &
Slave What will be the
memory mapping
for the DNP and
IED memory areas? There are many databases maintained within the module for all
the specific DNP data types and for the virtual master and
slave unit simulated in the module. For successful application
of the module, an understanding of the databases is required to
carefully design them.
Slave Will the secondary
DNP port have a
dial-up modem
attached? The secondary DNP slave port on the module can be
configured to have a dial-up modem attached. Use of this
feature requires bit 2 be set in the configuration word.
Additionally, many aspects of the modem timing features must
also be configured.
5.3.2 Data Requirements
This design phase defines what data elements are to be interfaced in the PLC
with the DNP master and slave. The module provides the following data types:
ƒ
digital input and output
ƒ counter
ƒ analog input and output
ƒ Floating-Point
All communications between the DNP master and the PLC is through these data
types. Therefore, all data to be used by the system must be contained and
configured in one of these data types.