Rs-485 Network Requirements - Bin Master C-100 Operator's Manual

3.2.5 4-20mA Output
The 4-20mA Output connection (CN3) is a two wire terminal block located on the far left of the printed
circuit board. It is identified with CN3 and labeled with 4-20. The two terminal screws marked + and –
should be connected to the proper positive and negative wires of the load. This output is powered and
capable of driving up to a 700
pair cable of 18 to 22 AWG wiring is sufficient. A shielded cable is not required; however, if one is used
leave it un-connected at the console.
The 4-20mA Output connection is optional and only needed when a 4-20mA output is needed to feed a
PLC or DCS system of the last measurement taken. This output can only represent one SmartBob
measurement but can be assigned to any SmartBob sensor on the network.

3.3 RS-485 Network Requirements

Both the SmartBob network (SB-485) and the Expansion network (EX-485) use RS-485 wiring and data
signaling techniques and must meet certain criteria for reliable operation. If these criteria are not met,
communications errors will most likely occur and result in failed measurements. Troubleshooting
communications errors can be expensive and time consuming, so BinMaster strongly encourages you to
take adequate time in understanding and installing the RS-485 networks and to use quality cabling and
connection techniques.
Summary of RS-485 requirements for BinMaster products:
All devices must be wired or connected in a daisy-chain fashion.
•
Use a quality twisted-pair cable with shield.
•
Maintain correct polarity between all devices wired to the network cable.
•
The two ends of the network cable must be terminated.
•
Biasing must be applied in only one place anywhere along the cable or network.
•
All devices on the network must support and be configured for the same protocol.
•
925-0270 Rev G
loop. Depending on the distance this wiring must go, a quality twisted-
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