![background image](http://html1.mh-extra.com/html/omega/dpf20-series/dpf20-series_user-manual_4064940027.webp)
27
DPF20 Frequency, rate, total or period counter
Instruction Manual
Option
RTU
Output type
Modbus RTU communication port
Function implemented
4 (Read_Input_Registers)
Addresses
01 to 247
Exception codes
see section
Registers
see section
2.3.1
Bus
RS-485
speed
57.6 Kbps to 600 bps
Data format
8n1 (standard), 8o1, 8n2, 8e1
bus terminator
not included
Isolation
1000 Vdc
Configuration
3 button front keypad
Temperature
operation from 0 to 50 ºC
storage from -20 to +70 ºC
Factory configuration
‘Address
1’
‘Speed
19.2 Kbps’
‘Format
8n1’
‘Decimal point Auto’
Installation allowed at
‘Opt.1’, ‘Opt.2’, ‘Opt.3’
Power
Opt.2
Opt.1
Op
t.3
B A G
B
A
G
Signal
B A G
Rear view DPF20
Register
Name
Description
Size
Refresh
Value : Series M
Value : Series K and S
0
DISPLAY1_L
Display value
16 bits
same
as display
999999 to -199999
9999 to -1999
1
DISPLAY1_H
16 bits
2
DECIMALS1
Decimals on display
16 bits
0 to 6
0 to 4
3
MAXMEM_L
Memory of maximum
16 bits
every
30 seconds
999999 to -199999
9999 to -1999
4
MAXMEM_H
16 bits
5
MINMEM_L
Memory of minimum
16 bits
999999 to -199999
9999 to -1999
6
MINMEM_H
16 bits
7
SETPOINT1_L
Setpoint 1 value
16 bits
every
2 seconds
999999 to -199999
9999 to -1999
8
SETPOINT1_H
16 bits
9
SETPOINT2_L
Setpoint 2 value
16 bits
999999 to -199999
9999 to -1999
10
SETPOINT2_H
16 bits
11
SETPOINT3_L
Setpoint 3 value
16 bits
999999 to -199999
9999 to -1999*
12
SETPOINT3_H
16 bits
13
STATUS
Alarm status
Instrument status
16 bits
same
as display
bit 0...7 alarm status
bit 8...16 instrument status
14 a 16
Reserved
Reserved
16 x 3 bits
Not accessible
Not accessible
Table 10 - Registers accessible via MODBUS-RTU.
All registers codified as binary numbers. Negative values are codified in two’s complement.
2.3
Module RTU
Module RTU provides 1 Modbus RTU communications port, to install
in DPF20 digital panel meters. Enables protocol function ‘4’ (‘
Read In
-
put Registers
’) to access the instrument registers (reading value, alarm
status, memory of maximum and minimum, setpoint values, ...).
Protocol configuration is performed from the frontal keypad of the
meter, by setting the parameters at the options configuration menu
(‘Opt.1’, ‘Opt.2’ or ‘Opt.3’ depending on the position the module is
installed).
Up to a maximum of 3 RTU modules can be installed in a single in
-
strument, all modules isolated between them and isolated from all
other circuits.
Modules RTU can be ordered pre-installed into a DPF20 digital panel
meter, or standalone for delayed installation, as they do not require
soldering or special configuration.
Module
Connections
Module RTU - Modbus RTU
Terminal B
B signal from RS-485 bus
Terminal A
A signal from RS-485 bus
Terminal G
GND
Table 11 - Connection terminals
2.3.1 Accessible registers