Schweitzer Engineering Laboratories SEL-700G Series, Инструкция по эксплуатации

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D.26
SEL-700G Relay Instruction Manual Date Code 20170814
DNP3 Communications
DNP3 Documentation
You can use the command SET DNP x, where x is the map number, to edit or
create custom DNP3 data maps. You can also use
AC
SEL
ERATOR
QuickSet
SEL-5030 Software, which is recommended for this purpose.
Scaling factors allow you to overcome the limitations imposed by the integer
nature of the default variations of Objects 30 and 32. For example, the device
rounds a value of 11.4 amps to 11 amps. You can use scaling to include
decimal point values by multiplying by a number larger than one. If you use
10 as a scaling factor, 11.4 amps are transmitted as 114. You must divide the
value by 10 in the master to see the original value including one decimal
place.
You can also use scaling to avoid overflowing the 16-bit maximum integer
value of 32767. For example, if you have a value that can reach 157834, you
cannot send it using DNP3 16-bit analog object variations. You could use a
scaling factor of 0.1 so that the maximum value reported is 15783. You can
then multiply the value by 10 in the master to see a value of 157830. You lose
some precision as the last digit is rounded off in the scaling process, but you
can transmit the scaled value using standard DNP3 Objects 30 and 32.
You can customize the DNP3 analog input map with per-point scaling, and
dead-band settings. Per-point customization is not necessary, but class scaling
(DECPLA, DECPLV, and DECPLM) and dead-band (ANADBA, ANADBV,
and ANADBM) settings are applied to indices that do not have per-point
entries. Unlike per-point scaling described previously, class-level scaling is
specified by an integer in the range 0–3 (inclusive), which indicates the
number of decimal place shifts. In other words, you should select 0 to multiply
by 1, 1 for 10, 2 for 100, or 3 for 1000.
If it is important to maintain tight data coherency (that is, all data read of a
certain type were sampled or calculated at the same time), then you should
group those data together within your custom map. For example, if you want
all the X-Side currents to be coherent, you should group points IAX_MAG,
IBX_MAG, ICX_MAG, and IGX_MAG together in the custom map. If points
are not grouped together, they might not come from the same data sample.
The following example describes how to create a custom DNP3 map by point
type. The example demonstrates the SEL ASCII command SET DNP for each
point type, but you can complete the entire configuration without saving
changes between point types. To do this, you simply continue entering data
and save the entire map at the end. Alternatively, you can use QuickSet to
simplify custom data map creation. Consider a case where you want to set the
AI points in a map as shown in Table D.13.
Table D.13 Sample Custom DNP3 AI Map (Sheet 1 of 2)
Desired
Point
Index Description Label Scaling
Dead
Band
0 X-Side IA magnitude IAX_MAG default default
1 X-Side IB magnitude IBX_MAG default default
2 X-Side IC magnitude ICX_MAG default default
3 Y-Side IA magnitude IAY_MAG default default
4 3-Phase Real Power P3X 5 default
5 X-Side AB Phase-to-Phase
Voltage Magnitude
VABX_MAG default default