User's Manual

The RTU connectors
EXTPS
GND
Power
Pd1
Pd0
BATT
Shield
GND
SOLAR
ext. stabilized Power Supply
to external Battery
Enclosure Connection
same type as supplied by Adcon
12−24VDC, .6Amax.
Fig. 10: A740 Connection with External Battery and Power Supply
Note: The cable used for the external power supply may not exceed 3 meters.
3.1.2 Serial Interface – RS-232
The serial interface on the A740 has the following characteristics:
• RS-232 data format
• V24 signal voltage levels
• DTE wiring (RxD, CTS are input and TxD, RTS are output)
To connect the A740 to a PC, use the following cable:
GND
CTS
RTS
RXD
RS−232
TXD
Shield
1 DCD
2 RXD
3 TXD
4 DTR
5 GND
Enclosure Connection
RI 9
CTS 8
RTS 7
DSR 6
9−pin female
SUB−D connector
using a short wire
connect pins 4 and 6
Fig. 11: Serial interface cable to connect a PC to an A740
3.1.3 Analog Inputs
The analog inputs can be used to measure a voltage or a current signal.
Depending on the configuration, the input signal range can be 0-1V, 0-2.5V, 0-5V
and 0-10V. Each input can be configured to one of the available input ranges.
To use the inputs with voltage signals, the Jumpers J7-J14 must be set to position
1-2 and 3-4.
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