User`s manual

MGate 4101-MB-PBS UM Hardware
3-6
Warranty 5 years
Adjustable Pull High/Low Resistors for the
Modbus Port (P1) in RS-485 Mode
SW 1 2 3
Pull High
Pull Low
Terminator
ON 1KΩ 1KΩ 120Ω
Default OFF 150Ω 150KΩ ---
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 MGate 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 that the two jumpers assigned to the serial port
are not shorted by jumper caps. This is the default setting.
To set the pull high/low resistors to 1 KΩ, make sure that the two jumpers assigned to the serial port are
shorted by jumper caps.
ATTENTION
Do not use the 1 KΩ setting on the MGate
when using the RS-232 interface. Doing so will degrade the RS-
232
signals and shorten the maximum allowed communication distance.
Reset Button