Rockwell Automation 20D PowerFlex 700S with Phase I Control Reference Manual - Manual (Page 111)

Rockwell Automation Publication PFLEX-RM002D-EN-E - August 2013 111
Detail Drive Configuration and Operation Chapter 1
Reference and Feedback values are floating-point values in the PowerFlex 700S.
Use the following logic to transmit and receive reference and feedback data as
integer data.
Datalink Programming
To read datalinks, the bits in parameter 723 [Dlink OutDataTyp] must be set
appropriately for each Datalink to select whether the data is floating point or
DINT.
Because the datalinks are transmitted and received through block transfers, the
data type in the controller is limited to 16-bit integers. To write or read floating
point or 32-bit integers the COP (copy) instruction must be utilized. The copy
instruction in ControlLogix performs a bitwise copy. Set the length of the copy
instruction to a value appropriate for the destination data type.
Transmitted Reference (counts) [Floating point Reference (RPM)
32768
Base motor RPM
[ ]
---------------------------------------------- ×
=
COP
Speed Reference Via Remote I/O to a PowerFlex 700S using a 20-COMM-R module.
The first move instruction is only for visual indication of the speed reference.
Calculate the reference as a DINT based on 32768 = base motor speed.
Then copy the DINT into 2, 16 bit tags sent over Remote I/O.
Move
Source
RIO_700S_Ref_RPM
1765.0
Dest RIO_700S_Ref_RPM
1765.0
Compute
Dest
RIO_700S_Ref_DINT
32768
Expression (RIO_700S_Ref_RPM/RIO_700S_Base_Motor_Speed)*32768
Copy File
Source
RIO_700S_Ref_DINT
Dest RIO_700S_BT_0[0]
Length 2
MOV
CPT
Floating point Feedback (RPM) [Feedback received (counts)
Base Motor RPM
32768
------------------------------------------ Ч
=