Rockwell Automation 7000 PowerFlex Medium Voltage AC Drive (B Frame) - ForGe Control - Manual (Page 150)

150 Rockwell Automation Publication 7000-UM202B-EN-P - June 2014
Chapter 3 Component Definition and Maintenance
Analog Inputs and Outputs
The PowerFlex 7000 “B” Frame offers one isolated process current loop
transmitter and three isolated process current loop receivers, embedded into the
control. These are accessible on the ACB.
The isolated Process Output is configured as 4-20 mA. The three isolated process
inputs are individually configurable for either a range of -10/0/+10V or 4-20
mA.
The following information details the connections for each input and output.
Current Loop Transmitter The current loop transmitter sends a 4-20 mA output to an external receiver. The
loop compliance on the transmitter is 12.5V. Loop compliance is the maximum
voltage at which a transmitter can generate to achieve the maximum current and
is usually a function of the power supply voltage. Therefore, the PowerFlex 7000
“B” Frame transmitter can drive a receiver with an input resistance up to 625 Ω.
The figure below shows a block diagram of the transmitter.
Figure 133 - Process Loop Transmitter block diagram
This type of transmitter is known as a 4-wire transmitter, and will “sink” current
from a receiver. The receiver is connected by two wires only from pins 20
(+ connection) and either pins 18, 19, 21 (- connection).
ŀ DSP
FPGA
+15V
Isolated
DC/DC
Converter
+15V
5V
Optical Interface
D/A
#
Current Boost
IFM
20
18
19
21