Overview - ABB AWT420 Operating Instruction

AW T4 2 0 | U N I V E R S A L 4 - W I R E , D U A L- I N P U T T R A N S M I T T E R | O I/A W T4 2 0 - E N R E V. B
3

Overview

The AWT420 is a universal 4-wire single or dual-input
transmitter suitable for the measurement and control of a wide
range of parameters including pH, ORP, conductivity, turbidity/
suspended solids and dissolved oxygen (depending on the
module[s] fitted).
Sensor and communication modules plug directly into their
corresponding slot on the transmitter backboard – see page
13 for module locations.
The AWT420 supports both traditional analog and advanced
digital EZLink sensors. The transmitter can be wall-, panel- or
pipe-mounted – see page 8.
Information from the sensor is sent to the transmitter via a
sensor interface board. The process reading is displayed on the
main page and can be displayed as a graph in the Chart View –
refer to page 29 for details of view options.
Diagnostic messages inform the user of the system status and
can be logged for review. The system status can also be
assessed remotely using optional HART®, MODBUS®, Profibus®
or Ethernet communications.
Installation and commissioning is simplified with plug-and-play
digital sensor connections and automatic sensor recognition
and set-up.
Display
Keypad
Analog output/
communication
SD card
modules
holder
Figure 1 AWT420 transmitter – main components
Transmitter
door lock
Tamper-evident seal
attachment point
Sensor modules
ANALOG pH INPUT pH INPUT
OUTPUT
1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8
7