D841/D850 Installation Manual
Page 6
008D-600-150
Use a power cable
of 0.75mm
2
(AWG
20)
Figure 4 - DC power supply socket connection
2.4.
Communication Connections
The D841 and D850 remote displays are available with two different communication
connection types, RS232/RS485 serial and Ethernet.
On power up, the display will attempt to automatically detect one of the
communication protocols described in Appendix A. Refer section 2.6
before connecting an indicator or PC with desired protocol.
2.4.1. Earthing Requirements for Cable Shields
Cable shields should ideally be connected to earth at one end for each of the
communications options below. As there is no provision for the shield connection at
the communications connection end of the display, it is recommended the shield be
terminated at the indicator (source) end.
Figure 5 - Shield Earthing
2.4.2. Serial Connection
The serial connection is used to transmit data to the remote display.
A shielded data cable should be used to prevent electrical noise interfering with the
operation of the unit.
Figure 6 - Serial socket connections
Notes
:
o
Pin 2 provides a 5V DC supply at a maximum current draw of 150mA. This
supply can be used by clean contacts on relays or switches to operate the
traffic lights.
o
GND
pin (7) is serial/digital input ground, NOT shield or power ground.
