SATEC AX-8 - Manual (Page 12)

9
4 Operation
4.
Refer to the Installation and Operation Manual of the specific Powermeter
for instructions on Analog Expander and communication parameters
setup.
4.1 Power Up
Close the power feed breaker; the ‘ON’ LED will light up.
4.2 Communication
When you program your powermeter to output data to external analog
outputs, the powermeter periodically updates the AX-8 analog outputs
(each 300-500 ms) via the pair of wires on the RS-422 communications
link used for transmitting data. At that time, the transmission (output) line
of the AX-8 is disconnected from the external network, while the receive
line is directly connected to the powermeter port so that the instrument is
constantly ‘listening’ to the network.
When data is requested from the powermeter by a master computer (or
controller), the powermeter instructs the AX-8 to switch the transmission
line to the external network, and then sends the response. After the
response message is sent out, the transmission line is disconnected from
the network and the powermeter continues updating the AX-8 outputs.
The AX-8 can work with different ASCII and non-ASCII network protocols.
If you use an ASCII communications protocol, set the switch #1 on the DIP
switch block S2 to OFF in order to put the AX-8 into ASCII mode. The
ASCII message frame should be ended with two characters CR/LF (ASCII
13 and 10). If you are using non-ASCII communications protocol such as
Modbus or DNP 3.0, set the switch #1 on the DIP switch block S2 to ON to
put the AX-8 into binary (transparent) mode. In this event, the AX-8 will not
decode the message frame and the transmission line is disconnected in
3.5 character time after the response message is sent out.
Indicator LEDs
The AX-8 is provided with a single Rx LED (network indication) and a pair
of Rx-Tx LEDs (Powermeter indication) which operate as shown in Figure
4-1: