VPG BHL Nobel AST 3, Operating Instructions, Quick Installation

Page: 10 / 26

Operating instructions, Quick installation
6
Power supply
Terminals 17, 18.
The AST 3 module is powered by 24 V DC.
Rail mounted power supplies can be ordered
from Nobel Weighing Systems.
Analogue output
Terminals 24, 25.
The measurement value is presented as a current
or voltage signal, according to set-up selection.
Connect the cable shield to ground, preferably to
a ground terminal at the mounting rail.
Serial communication
Terminals 19 – 23.
Set-up by serial communication is needed to take
AST 3B into operation. All AST 3 have a serial port
for RS-485 on 2-wires or 4-wires with common
earth (COM). If necessary, a converter unit should
be connected to adapt the interfaces.
The line must have 120 ohm termination at both
ends. For AST 3 it should be mounted on separate
terminals and connected according to the diagrams.
Refer to manufacturer instructions for termination
at the control unit (PC), or at the converter unit.
Connect the cable shield to ground, preferably to
a ground terminal at the mounting rail.
Set-up programme deltaCOM
AST 3B must be connected to transducer(s) and power supply, and also to a
PC with Windows 95/98/2000/XP/NT4.0 to make set-up possible. Included in
the AST 3 delivery is a diskette with the set-up programme deltaCOM. This
diskette also contains instructions for connection and set-up of the serial
communication between the instrument and the PC.
To install the programme, insert the diskette in the computer, press the ‘Start’
button and select ‘Run...’ from the menu, type [drive letter]:\setup in the dialogue
box and then follow instructions on the screen.
If nothing else is stated, the programme deltaCOM and a ReadMe file will be
found in Start > Program > deltaCOM.
By use of deltaCOM it is possible to find all AST 3 modules communicating with
the PC, and to study and edit all set-up parameters for these modules.
IN1
IN2
15
16
+
OUT+
OUT–
24
25
2-wire
*
Terminating resistor on separate
terminals at the last unit on the line.
120Ω
19
20
21
22
23
TXD–
TXD+
RXD–
RXD+
COM.
4-wire
Terminating resistor on separate
terminals at the last unit on the line.
*
*
19
20
21
22
23
TXD–
TXD+
RXD–
RXD+
COM.
120Ω
*
120Ω
*