HES
User Manual
HART to Ethernet Gateway System
226-710-00A
September 2018
www.miinet.com
[66]
Moore Industries-International, Inc.
HART Field Device Registers
The MODBUS registers are organized into groups. Each group starts at a fixed MODBUS
register but the variables will be organized differently based on the selected mapping and
compression options.
NOTE:
The MODBUS registers and data for most of these parameters are also
available on the HES generated web pages.
The following equations are used for calculating the MODBUS registers for each of the
parameters.
Mapping By Variable Type (PV1, PV2, PV3..):
MODBUS register =
b + (o*t) + (r*p)
Mapping By Device Type (PV1, SV1, TV1..):
MODBUS register =
b + o + (g*p)
The following variables can be found on the appropriate table (below)
b = MODBUS group base register
g = Device group size
r = Parameter size (number of registers)
o = Parameter (Register) offset
These variables are determined by your HES’ specific configuration
p = Device position (calculated)
t = Total number of HART field devices
x = HES channel number (1 thru 4)
y = Device number on Channel x
Use without compression
When compression of unused devices is NOT used, then the device position (p) is always
calculated assuming 16 devices per channel. Device position can be a value from 0 to 63.
p = [(x-1)*16] + (y – 1)
Where x is the HES channel number (1 to 4) and y is the device number on that channel (1-16).
For example, when device compression is turned off, the 3
rd
device on channel 4 has a device
position of [(4-1)*16] + (3-1) = 50
