Modbus commands and registers table, Supported modbus commands, Read holding registers – 03h – NOVUS DigiRail-VA User Manual

Page 17: Write single register – 06h, Write multiple registers – 16h, Table of holding registers, Details about some registers

Advertising
background image

DigiRail-VA

NOVUS AUTOAMTION

17/19

MODBUS COMMANDS AND REGISTERS TABLE

The DigiRail-VA accepts some Modbus commands that are sent to its Modbus’ own address, operating as a network
slave. Commands forwarded to other slaves (routing) will be sent in a transparent way. The following listed Modbus RTU
commands (functions) are implemented, and these are interpreted by DigiRail-VA. For further information about each
command and the Modbus protocol in general, access the website

www.modbus.org

.

SUPPORTED MODBUS COMMANDS

READ HOLDING REGISTERS – 03H

This command can be used to read a value of one or up to the maximum consecutive holding registers, as shown in the
“Table of Holding Registers”.

WRITE SINGLE REGISTER – 06H

This command can be used to write on a holding register, as shown in the “Table of Holding Registers”.

WRITE MULTIPLE REGISTERS – 16H

This command can be used to write in multiple holding registers, as shown in the “Table of Holding Registers”.

TABLE OF HOLDING REGISTERS

The specified addresses correspond to the low level physical addresses, where zero (0) corresponds to the address PLC
40001. The Minimum and Maximum columns have a range of valid values for each parameter. The R/W column
indicates if the parameter is for reading and writing (R/W) or if it is only reading ® The Mnemonic SuperView states what
the register mnemonic is for in the SuperView software.

Address

Description

Minimum

Maximum

R/W

Mnemonic

SuperView

0

RMS Voltage (floating point – word high)

0.0

+3.4e+38

R

1

Voltage RMS (floating point – word low)

2

Current RMS (floating point – word high)

0.0

+3.4e+38

R

3

Current RMS (floating point – word low)

8

Active Power / real power (floating point – word high)

0.0

+3.4e+38

R

9

Active Power / real power (floating point – word low)

10

Apparent power (floating point – word high)

0.0

+3.4e+38

R

11

Apparent power (floating point – word low)

12

Reactive power (floating point – word high)

0.0

+3.4e+38

R

13

Reactive power (floating point – word low)

14

Power factor (floating point – word high)

-1.0

R

15

Power factor (floating point – word low)

16

Frequency (floating point – word high)

0.0

+3.4e+38

R

17

Frequency (floating point – word low)

20

Voltage RMS x 10 (integer 16 bits unsigned)

0

65535

R

VoltageRMS

21

Current RMS x 100 (integer 16 bits unsigned)

0

65535

R

CurrentRMS

22

Maximum peak voltage x 10 (integer 16 bits unsigned)

0

65535

R

MaxVoltagePeak

23

Maximum peak current x 100 (integer 16 bits unsigned)

0

65535

R

MaxCurrentPeak

24

Active Power (real power) x 10 (integer 16 bits

unsigned)

0

65535

R

ActivePower

25

Apparent power x 10 (integer 16 bits unsigned)

0

65535

R

ApparentPower

26

Reactive power x 10 (integer 16 bits unsigned)

0

65535

R

ReactivePower

27

Power factor x 1000 (integer 16 bits signed)

-1000

1000

R

PowerFactor

28

Frequency x 10 (integer 16 bits unsigned)

0

650

R

Frequency

31

Sign of the Reactive power (0 = inductive, 1 =

capacitive)

0

1

R

LeadLag

200

Serial number (word high)

0

65535

R

SerialNumber_H

201

Serial number (word low)

0

65535

R

SerialNumber_L

202

Firmware Version

0

999

R

FirmwareVersion

DETAILS ABOUT SOME REGISTERS

REGISTERS 20 TO 28 – MEASUREMENT VALUE IN INTEGER FORMAT

Reports the value of the respective variable input. The value will be multiplied by 10, 100 or 1000 depending on the
variable. Example: a value of 217.8 reads as 2178.

Advertising