Leviton 71D03 - RTU Programming and Scripting

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This section is for the programmer of the RTU or host system, and describes meter and
element addressing, register locations, data formats, and protocol examples.
7.1 Register Organization
The VerifEye
®
meter communicates through the reading and writing of registers.
Registers are organized into functional groups, and are compliant with the SunSpec
Modbus interface model.
• SunSpec Common Registers
• SunSpec TCP Network Stack Registers
• SunSpec Serial Interface Registers
• SunSpec Energy Meter
The complete register set is included as an Excel le on the supplied thumb drive,
or go to https://www.leviton.com, and go to the S7000/7100 product page's
Support/Downloads section.
7.2 Element vs. System Scope
Element
Physically, the term Element describes groups of three channel sections identied
by an alphabetic letter on the silk screen of the PCBA (A,B,C,D). In a three-phase
power system, these channel sections correspond to electric circuits.
Logically, the term Element describes the scope of a data item, register or point
(Modbus register or BACnet object). Each Element base point is accessed by
choosing the appropriate Modbus address, BACnet object range, or BACnet
structured view. Elements have points that refer to individual channels or to
sums or averages of those channels. Registers that contain data in more than
one channel, are identied as being sums or averages of the enabled channels
within an Element. In a BACnet structured view, an Element represents a level of
organization for related points.
Channel
Channels are identied on the circuit board as CH1, CH2, or CH3 and represent
physical CT inputs. In three-phase system congurations, these correspond to
a current load on a corresponding line voltage. In single-phase congurations,
they are used to identify a CT location. Registers providing data for an individual
channel are also described as elements in their scope as a unique value exists for
each Slave Address or BACnet object instance.
System
The term “System” refers to registers dening the characteristics of the entire circuit
board. System registers report the same value independent of the slave address.
Under BACnet structured view the system points are grouped together.
7 RTU PROGRAMMING AND SCRIPTING
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