Emerson FM-3 User Manual
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FM-3 Programming Module Reference Manual
An external device such as a Human Machine Interface (HMI) or PLC can be used to monitor
or edit individual FM-3 module parameters. The FM-3 module and drives use a 32-bit
Modbus RTU communications protocol.
In order to view or modify a parameter, a Modbus address must be assigned to the specific
parameter. To do this, locate the parameter you wish to read/write to or from in the variables
list in the middle of the view. Once you have found the proper parameter, click and hold the
left mouse button over the parameter. While still holding the button on your mouse, drag the
parameter into the Modbus window area on the right of the view. Now let go of the mouse
button.
A “New Assignment” dialog box will appear. This will automatically assign the next
available modbus address, or allow you to enter a different Modbus address. Once you click
on OK, then you will be able to read or write the parameter at that address.
Figure 64:
Modbus Address Assignment Box
Address ranges are as follows:
Any individual Modbus address can be deleted by highlighting the parameter you wish to
delete, and clicking on the Remove button. The address selected will be removed from the
list. If you wish to delete all of the Modbus addresses that have been created, then simply click
on the Remove All button. All of the addresses will disappear and the Modbus window will
be empty.
Some Modbus addresses have been reserved and can not be assigned:
39980-39999 and 49501-49999.
Address Range
Accessibility
Type
Data Size
4xxxx
Read/Write
Register
32 bit word
3xxxx
Read Only
Register
32 bit word
1xxxx
Read Only
Input Bits
bit
0xxxx
Read/Write
Coil
bit