BB2-7030 User Guide – Rev. 1.0
Page 62
17.
Hardware
Guide
Wire the BB2-7030 as illustrated above. Follow all conventional standards for wiring of EIA-485
networks when connecting the MS/TP EIA-485 (RS485) network. This includes use and
termination of shield, termination of the network, and grounding.
IMPORTANT: Although EIA-485 (RS485) is thought of as a 2-wire network, you MUST
include a third conductor connected to GND or common at each device so that all devices are
operating at close to the same ground potential. Proper grounding of equipment should ensure
proper operation without the third conductor; however, proper grounding often cannot be relied
upon. If large common mode voltages are present, you may even need to insert optically isolated
repeaters between EIA-485 devices.
Use standard CAT5 cables for Ethernet connections. Use control wire as applicable for local
electrical codes for connecting the 24V (AC or DC) power supply.
Note that in addition to connecting power supply common to a GND terminal, you must also
connect a GND terminal to earth ground in order to ensure proper ESD protection.