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1 Introduction
1.
The AX-8 Analog Expander is an instrument that enables Powermeters to interface
with other devices that require analog signals. The AX-8 can be connected to any
Powermeter equipped with an RS-422 communication port and analog expander
option.
The AX-8 provides up to 8 analog outputs. Two units can be connected in
sequence, providing as many as 16 analog outputs with use of one Powermeter
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.
For information on analog output and analog expander setup and connections,
refer to the Installation and Operation Manual of the specific Powermeter.
Features
Accuracy
- The AX-8 provides 8 or 9 bit resolution on each analog output. Output
values on all channels are updated continuously at a rate of 0.3 to 0.5 seconds,
depending on the speed of communication (baud rate).
Flexibility
- The analog outputs are provided with
current output options
of 0-20
mA and 4-20 mA, 0-1 mA and
±
1 mA , and
voltage output options
of 0-10V DC
and
±
10V DC. Depending on the specific model of Powermeter, a wide range of
output values are user-selectable, from the Powermeter front panel or via
communications software.
Installation
- DIN rail or wall mounting. No auxiliary power supply is required; an
internal switching power supply with a wide AC/DC range is provided.
Communications
- The AX-8 is connected to the Powermeter using a twisted pair
cable via the RS-422 port, using ASCII, Modbus or DNP3.0 protocols. This allows
communication over a distance of up to 1000 meters at a baud rate of up to 19,200
bps. Installation of the AX-8 does not interfere with the inclusion of the Powermeter
in a communication network (RS-422 or RS-485) of up to 31 Powermeters.
Figure
1-1
shows a typical communication network with two AX-8 expanders.
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If your Powermeter supports 7 (14) channels, then the AX-8 will also provide 7 (14) channels.
