User`s manual

ACH550-01 User's Manual
124 Application macros and wiring
Connection examples of two-wire and three-wire
sensors
Many ACH550 applications use process PI(D) and need a
feedback signal from the process. The feedback signal is
typically connected to analogue input 2 (AI2).
The macro wiring diagrams for each macro earlier in this chapter
use an externally powered sensor (connections not shown). The
figures below give examples of connections using a two-wire or
three-wire sensor/transmitter supplied by the drive auxiliary
voltage output.
Two-wire sensor/transmitter
Note: The sensor is supplied through its current output and the
drive feeds the supply voltage (+24 V). Thus the output signal
must be 4…20 mA, not 0…20 mA.
Three-wire sensor/transmitter
X1 / control board
5 AI2 Process actual value measurement,
4…20mA, R
in
= 100 ohm
6AGND
…
X1 / control board
10 +24 V Auxiliary voltage output, non-isolated,
24 V DC, 250 mA
11 GND
P
I
4…20 mA
-
+
X1 / control board
5 AI2 Process actual value measurement,
0(4) … 20 mA, R
in
= 100 ohm
6AGND
…
X1 / control board
10 +24 V Auxiliary voltage output, non-isolated,
24 V DC, 250 mA
11 GND
P
I
0(4)…20 mA
-
+
OUT