Moxa Technologies CN2600 Series - Adjustable Pull High;Low Resistors for the RS-485 Port

CN2600 Series Hardware Installation
2-5
Adjustable Pull High/Low Resistors for the
RS-485 Port
In some critical environments, you may need to add termination resistors to prevent the reflection of serial
signals. When using termination resistors, it is important to set the pull high/low resistors correctly so that the
electrical signal is not corrupted. The CN2600 uses jumper settings or DIP switches to set the pull high/low
resistor values for each serial port.
To set the pull high/low resistors to 150 KΩ, make sure both of the assigned DIP switches are in the OFF
position. This is the default setting.
To set the pull high/low resistors to 1 KΩ, make sure both of the assigned DIP switches are in the ON position.
ATTENTION
Do not use the 1 KΩ setting on the CN26
50 when using the RS-232 interface. Doing so will degrade the RS-
232
signals, shorten the maximum allowed communication distance, and the Rx LED
may light up.