Acromag ACC1000, Instruction Manual

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Serial Communication Converters & Adapters
Instruction Manual
11
Connections
A APMA7420 cable is provided to connect the
APM765/VPM3000 meter to the APMA7422 adapter.
Figure 16 shows the APMA7420 cable details.
Figure 16. Standard Modular Cable Wiring
Figure 17 details the wiring connections from the
APMA7422 to an RS-485 serial converter (such as the
ACC1001 or ACC1003) for a four-wire network.
APMA7422 to RS-485 Serial Converter
Connections
RS-485 Serial
Converter APMA7422
RS-485 Adapter
Figure 17. Connections for APMA7422 to Serial Converter
If the serial converter is configured for a two-wire
network then the requirement to externally wire the DO
to the DI and the /DO to the /DI on the APMA7422
screw terminal connector is needed.
ACC1001 RS-232 to RS-485
Converter
Description
The ACC1001 converts unbalanced, full-duplex RS-232
signals to balanced, full or half-duplex RS-422 or
RS-485 signals.
The RS-232 port, configured as a DTE port, has a
female DB9 connector with pins 2 (RX output),
3 (TX input), and 5 (Signal Ground). Pins 7 (RTS) and
8 (CTS) are tied together, and pins 1 (CD), 4 (DTR),
and 6 (DSR) are tied together. The RS-485 terminal
blocks support Transmit Data (DO) and (/DO), Receive
Data (DI) and (/DI), and Signal Ground. A separate
terminal block supports the power input (+12VDC) and
power ground (GND).
Baud rates are automatic and handled by the
ACC1001.
The ACC1001 has three diagnostic LEDs: a Power (P)
LED to show when the converter is powered properly, a
Transmit Data (TX) LED to show when the converter is
sending data out from the PC side, and a Receive Data
(RX) LED to show when the converter is receiving data
from the network side.
The DIP switch SW1 is located between the screw
terminal connectors and allows for system
configurations.
Installation
The DIP switch SW1 allows for several different
options. Factory settings for the switch are shown in
Figure 18
.
Figure 18. ACC1001 Connections and DIP Switch Settings
The TERM switch position adds an internal 120 ohm
termination resistor when ON (up). Termination should
be used on both ends of the network with high data
rates and long wiring runs.
(WH) 1
(BK) 2
(R) 3
(G) 4
(Y) 5
(BL) 6
1
2
3
4
5
6
1 2 3 4 5
ON
GND
SW1
Switch in
ON/UP
Position