QTech Q23, Руководство пользователя

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CONFIGURATION
Q23 Expansion Module Page 27
Location of Power Control Jumper J23.
The Q23 Module incorporates a Remote Power Control circuit that automatically shuts down the Q23 Module to
prevent total battery discharging and also protect against under-voltage erratic operation of the module.
When jumper J23 is installed the remote Power Control function is disabled and the Q23 module will remain
permanently ON whenever power is applied to the unit. When jumper J23 is open the Q23 Module will power up
whenever the Remote Power Control line is taken high and power is applied to the module.
RS485 Serial Port
The diagram below shows the location of the jumper J24 associated with the RS485 port configuration at the
bottom left of the Q23 Module as viewed with the front display panel to the right.
Location of RS485 Termination Jumper J24.
The RS485 serial port is used for inter-module long distance, high speed communications. The RS485 serial port
has inbuilt provision for line termination. In RS485 applications, especially over long lines, the RS485 transceivers
at either end of the line should be terminated with a 120-ohm load. In multi-drop RS485 applications only the far
end RS485 transceivers should be terminated.
RS485 Line Termination
J24
TERMINATED INSTALL
UN-TERMINATED OPEN
RS485 Line Termination Jumper Configurations.
To enable the 120 ohm line terminating resistor install a shorting link on J24