Obvius AcquiSuite Ally 12 - RTU Programming and Scripting - Details; Register Organization; Element Vs System Scope

AcquiSuite Ally 12 & 48 User Guide (Rev D)
49 | P a g e
RTU PROGRAMMING AND SCRIPTING - DETAILS
This section is intended for the programmer of the RTU or host system and includes
details about meter and element addressing, register locations, data formats and
protocol examples.
Register Organization
The AcquiSuite™ Ally 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
▪ Obvius Factory Registers
▪ Obvius User Command Registers
▪ Obvius User Configuration Registers
▪ Obvius Metrology Registers
▪ Obvius Daughter Card Registers
▪ Obvius Waveform Capture Registers
The complete register set is included as an Excel file on the supplied thumb drive.
ELEMENT VS SYSTEM SCOPE
Element
The term “element” is used in two contexts. Physically the term Element is used to describe groups of
three channel sections identified by alphabetic letter on the silk screen of the PCBA (ie A,B,C,D). In a three
phase power system these 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 based point is accessed
by choosing the appropriate Modbus address, BACnet object range, or BACnet structured view. Elements
in turn have points that refer to individual channels or to SUMS or AVERAGES of those channels. Registers
that contain data inclusive of more than one channel are identified as being either 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 identified on the circuit board as CH1, CH2, or CH3 and represent physical CT inputs. In three
phase system configurations, these correspond to a current load on a corresponding line voltage. In single
phase configurations, they are just 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 defining 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.