ProSoft Technology MVI56E-MCM/MCMXT User Manual

Page 50

Advertising
background image

Configuration as a Modbus Master

MVI56E-MCM ♦ ControlLogix Platform

User Manual

Modbus Communication Module

Page 50 of 199

ProSoft Technology, Inc.

June 18, 2014

The above command will take the data from MCM.DATA.W

RITE

D

ATA

[0]

TO

[13]

and write this information to the Slave device node #1 addresses 40261 to
40274.

2.4.4 Read Floats with Single Modbus Register Address

(Enron/Daniel Float)

Some Modbus Slave devices use a single Modbus address to store 32 bits of
data. This type of data is typically referred to as Enron or Daniel Floating-Point.

A device that uses this addressing method may have the following Modbus
Memory Map.

Address

Data Type

Parameter

47001

32 bit REAL

Demand

47002

32 bit REAL

Reactive Power

47003

32 bit REAL

Apparent Power

47004

32 bit REAL

Power Factor

47005

32 bit REAL

Voltage: Line to Line

47006

32 bit REAL

Voltage: Line to Neutral

47007

32 bit REAL

Current

This type of device uses one Modbus address per floating-point register. To read
these values from the Slave device, configure the following command within the
module.

Notice that the count is now set to a value of 7. Because the Slave device utilizes
only 7 Modbus addresses, a count of 7 will cause the Slave to respond with 14
registers (28 bytes) of information.

Important: This command will still occupy 14 register within the MCM.DATA.R

EAD

D

ATA

array. You

must not use addresses 1000 to 1013 in the IntAddress field for any other Modbus Master

commands.

The COP

statement for this type of data is the same as shown in Read Multiple

Floating-Point Registers (page 48).

Advertising