HES
User Manual
HART to Ethernet Gateway System
226-710-00A
September 2018
www.miinet.com
[67]
Moore Industries-International, Inc.
Use with compression
When compression of unused devices IS used, then you need to know the number of devices
on each channel to calculate the device position (p) and total number of devices on all channels
(t).
So for a device on channel 3 you need to know how many devices are on channels 1 and 2 and
also the total number of devices on all 4 channels. Device position can be a value from 0 to 63.
For example:
Channel 1
Channel 2
Channel 3
Channel 4
6 devices
5 devices
2 devices
1 device
Total number of devices on all channels t = 6+5+2+1 = 14;
For Ch1 Dev3, device position p = 2;
For Ch2 Dev4, device position p = 6 + 4 – 1 = 9;
For Ch4 Dev1, device position p = 6 + 5 + 2 + 1 – 1 = 13
Variables b, g, r and o are provided in the tables below for every field device parameter stored
in the HES. Table 1 is used for all mapping and compression except when CMD3/CMD9
compression is selected. When CMD3/CMD9 compression is selected, Table 2
should be used.
Example Calculations:
HES is configured with 14 field devices
Channel 1
Channel 2
Channel 3
Channel 4
6 devices
5 devices
2 devices
1 device
1) Locate Integer value of PV for HART Device 3 on Channel 2
Mapped by Variable Type, NO compression*:
MODBUS register =
b + (o*t) + (r*p)
t=64, p=18;
From Table 1: b=2049, o=0, r=1
MODBUS register = 2049 + (0*64) + (1*18) =
2067
*with NO compression each channel is assumed to have 16 devices
2) Locate Float value of SV for HART Device 1 on Channel 3
