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User manual for meter with U/I input PD72S
The device parameters and display value are available via RS-485 interface, as HOLDING-type
registers (numeric values are given in U2 code) of Modbus RTU protocol. The registers (or
groups of the registers) can be read by 03h function, and wrote by 06h (single registers) or 10h
(group of the registers) accordingly to Modbus RTU specification. Maximum group size for 03h
and 10h functions cannot exceeds 16 registers (for single frame).
The device interprets the broadcast messages, but then do not sends the answers.
11.1. LIST OF REGISTERS
Register Write
Range
Register description
01h
No
-999 ÷ 9999
Measurement value (no decimal point)
02h
No
0h, A0h, 60h
The status of the current measurement;
0h
- data valid;
A0h
- top border of the measurement range is exceeded;
60h
- bottom border of the measurement range is exceeded;
03h
Yes
0 ÷ 3
“
Pnt
” parameter in “
InPt
” menu (decimal point position)
0
-
“
0
”;
1
-
“
0.0
”;
2
-
“
0.00
”;
3
-
“
0.000
”
04h
Yes
see descr.
State of the relays and alarm LED (binary format)
(1 - on, 0 - off):
00000000 000e00ba
a
- relay R1;
b
- relay R2;
e
- alarm LED;
If written, only
a
,
b
bits are important (others are ignored) these bits
allows user to control the relays via RS-485 interface
06h
No
-999 ÷ 9999
Peak (drop) value (no decimal point)
10h
Yes
0 ÷ 5
“
tyPE
” parameter in “
InPt
” menu (nominal input range).
0
- 0-20 mA range;
1
- 4-20 mA range;
2
- 0-10 V range;
3
- 2-10 V range;
4
- 0-5 V range;
5
- 1-5 V range
11h
Yes
0 ÷ 3
“
CHAr
” parameter in “
InPt
” menu (characteristic type)
0
- linear ;
1
- square;
2
- square root;
3
- user defined
12h
Yes
0 ÷ 5
“
FiLt
” parameter in “
InPt
” menu (measurement filtering rate)
13h
Yes
0 ÷ 3
“
Pnt
”parameter in “
InPt
” menu (the copy of 03h register, decimal
point position)
0
-
“
0
”;
1
-
“
0.0
”;
2
-
“
0.00
”;
3
-
“
0.000
”
14h
Yes
-999 ÷ 9999
“
Lo C
” parameter in “
InPt
” menu, no decimal point included
15h
Yes
-999 ÷ 9999
“
Hi C
” parameter in “
InPt
” menu, no decimal point included
16h
Yes
0 ÷ 999
“
Lo r
” parameter in “
InPt
” menu, in 0.1 %
17h
Yes
0 ÷ 199
“
Hi r
” parameter in “
InPt
” menu, in 0.1 %
20h
2
Yes
0 ÷ 199
Device address
21h
No
20F7h
Device identification code (ID)
22h
3
Yes
0 ÷ 7
“bAud”
parameter in
“rS”
menu (baud rate);
0
- 1200 baud;
1
- 2400 baud;
2
- 4800 baud;
3
- 9600 baud;
4
- 19200 baud;
5
- 38400 baud;
6
- 57600 baud;
7
- 115200 baud
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