GE D90 Plus, Руководство по связи

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214 D90
PLUS
LINE DISTANCE PROTECTION SYSTEM – COMMUNICATIONS GUIDE
DNP POINTS CHAPTER 3: DNP COMMUNICATION
A counter freeze command has no meaning for counters 8 and 9. The D90
Plus
digital
counter values are represented as 32-bit integers. The DNP 3.0 protocol defines counters
to be unsigned integers. Take care when interpreting negative counter values.
Analog input points
The DNP analog input data points are configured through the Settings > Communications
> DNP > User Point List menu item.
It is important to note that 16-bit and 32-bit variations of analog inputs are transmitted
through DNP as signed numbers. Even for analog input points that are not valid as
negative values, the maximum positive representation is 32767 for 16-bit values and
2147483647 for 32-bit values. This is a DNP requirement.
The deadbands for all analog input points are in the same units as the analog input
quantity. For example, an analog input quantity measured in volts has a corresponding
deadband in units of volts. This is in conformance with DNP Technical Bulletin 9809-001:
Analog Input Reporting Deadband . Relay settings are available to set default deadband
values according to data type. Deadbands for individual analog input points can be set
using DNP object 34.
The analog input DNP parameters are as follows:
•
Static (steady-state) object number — 30
• Change event object number — 32
• Request function codes supported — 1 (read), 2 (write, deadbands only), 22 (assign
class)
• Static variation reported when variation 0 requested — 1 (32-bit analog input)
• Change event variation reported when variation 0 requested — 1 (analog change
event without time)
• Change event scan rate — Defaults to 500 ms
• Change event buffer size — 256
• Default class for all points — 2
DNP user point list settings
The binary and analog inputs points for the DNP protocol can be configured to a maximum
of 256 points. The value for each point is user-programmable and can be configured by
assigning FlexLogic operands for binary inputs or FlexAnalog parameters for analog
inputs.
The DNP point lists always begin with point 0 and end at the first “Off” value. Since DNP
point lists must be in one continuous block, any points assigned after the first “Off” point
are ignored.
Select the
Settings > Communications > DNP > User Point List menu to open the DNP
user point list configuration window.