MD-124 HW Manual
Hardware Installation and Peripherals
3-3
Connecting Power Sources
The MD-119 offers 24 VDC power input with the terminal block, and also comes with a 110 to 230 VAC power
input. If power is supplied properly, the
Power
LED will light up. To enable the power failover function, connect
both AC and DC power inputs.
For safety reasons, please use cables with the following specifications:
Wire range: 14-22 AWG, torque 7 lb
Grounding the MD-119
Grounding and proper wiring layout help limit the effects of noise from electromagnetic interference (EMI). The
ground wire must be a minimum 18 AWG, and must be connected (via the grounding screw) prior to connecting
the power. The ground connector is located on the bottom panel of the display, as shown in the
Appearance
and Layout
diagram on page 2-2.
ATTENTION
This product is intended to be mounted to a well-grounded mounting surface, such as a metal panel.
Connecting Data Transmission Cables
This section describes how to connect the MD-119 display to various interfaces.
Connecting to a Serial Device
Use a serial cable to plug your serial device into the display’s serial port. Please note that serial port 1 is
reserved for the manufacturer’s configuration process; only serial port 2 is available for connecting serial
perhipherals. Serial port 2 terminates in a male 9-pin D-Sub (DE9) connector, and can be software-configured
as an RS-232, RS-422, or RS-485 interface. The pin assignments are shown in the table on the following page:
DB9 Male Port
RS-232/422/485 Pinouts
Pin
RS-232
RS-422
RS-485
(4-wire)
RS-485
(2-wire)
1
DCD
TxDA(-)
TxDA(-)
–
2
RxD
TxDB(+)
TxDB(+)
–
3
TxD
RxDB(+)
RxDB(+)
DataB(+)
4
DTR
RxDA(-)
RxDA(-)
DataA(-)
5
GND
GND
GND
GND
6
DSR
–
–
–
7
RTS
–
–
–
8
CTS
–
–
–
