Configuration in STEP 7
5.6 Configuring networks and network nodes in STEP 7 / NetPro
TIM DNP3
System Manual, 12/2015, C79000-G8976-C253-04
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– DNP3 mode
For dial-up networks, both the polling and the spontaneous (unsolicited) mode are
possible. In spontaneous mode, a TIM with an important data change transfers its
data unsolicited and waits for the acknowledgment from the partner. Prior to the actual
data transfer, the TIM must first establish a dial-up connection to the partner.
Following successful transmission of the data, the TIM waits for the acknowledgment.
Following this, the dial-up connection is terminated immediately again if the partner
does not use the existing connection to transfer any existing data.
The unsolicited transfer is configured in the properties dialog of the TIM > "Interfaces"
tab > "DNP3 parameters" button: "DNP3 parameters" dialog > "DNP3 basic
parameters" > "Unsolicited transfer"
In the "Message parameters" box, the following parameters are displayed grayed out:
● Message format:
For DNP3 dedicated lines, this parameter has the default setting "FT3" and this cannot be
changed. FT3 is recommended in the DNP3 specification.
For dial-up networks, the following values can be configured:
– FT1.2 (8E1):
Character format 8 data bits,
even parity, 1 start bit, 1 stop bit
Modem setting: Data format 11 bits
– FT2 (8N1):
Character format 8 data bits,
no parity, 1 start bit, 1 stop bit
Modem setting: Data format 10 bits
– FT3:
Character format 8 data bits,
no parity, 1 start bit, 1 stop bit
Modem setting: Data format 10 bits
You will find information on setting the message format of the modems in the
documentation of the modems, refer to the Appendix.
● Acknowledgment:
The acknowledgment type does not depend on the modem used. It is set dependent on
the quality of the transmission line.
Default: short acknowl.
For DNP3 dedicated lines, this parameter has the default setting "Short acknowl." and
this cannot be changed.
For dial-up networks, the following values can be configured:
– short acknowl.:
consists of one byte.
– long acknowl.:
consists of 5 bytes. The long acknowledgment is advisable in applications when
interference produces spurious characters on the transmission line that could be