CIAT AQUACIATPOWER CONNECT TOUCH ILD 602R, Инструкция по эксплуатации

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EN - 11 AQUACIAT
POWER
4 - HARDWARE
No.1 RS485 wiring diagram (RECOMMENDED)
No. 2 RS485 wiring diagram (CORRECT)
No. 3 RS485 wiring diagram (CORRECT)
No. 4 RS485 wiring diagram (INCORRECT - Do not use!)
No. 5 RS485 wiring diagram (INCORRECT - Do not use!)
4.8 RS485 wiring (best practice)
For RS485 ports, one of the following cables can be used:
■ For Proprietary Protocol or Modbus communication which is
over 300 m or in a noisy environment with Variable Frequency
Drive (VFD), a cable with two twisted pairs is recommended.
For example, Belden 3106A or Alpha Wire 6454.
■ For applications where the length of the cable is up to 300 m
and there is no Variable Frequency Drive (VFD), it is possible
to use cost-effective cable solutions, for example, Belden 8772.
Note that “+” and “-” are communication signals and they are
from the same twisted pair.
The signal ground could be a single wire or a twisted pair and it
should be connected to the “C” pin of J10 (Modbus RTU) or J7
(Proprietary Protocol). This wire is required so that all nodes on the
bus share a common ground reference connection.
If a shield is used, then the shield cable should be properly
terminated and connected as short as possible at ONLY
ONE END to the chassis ground (4.3-inch controllers).
4.8.1 RS485 wiring: 4.3-inch controller
The following diagrams illustrate possible RS485 wiring
schemes for 4.3-inch controllers.
The first wiring scheme is the best option (RECOMMENDED),
but the second or the third wiring can also be used.
4.8.2 RS485: Daisy chain configuration
The following illustration shows proper 3-wire termination with
a shield in a daisy chain configuration.
Legend
①
Shield
②
Keep shield continued
③
Connect shield to earth ground only at one point
End of Line Resistor: Termination is only needed when
running at bus at very high speed over long distances.
The speed of the bus and the cable distance determines
whether termination is needed. It is meant to balance the bus to
minimize the ringing that may be caused by fast signals and the
inductance of the cabling.
At 9600 baud, termination will have little or no effect on the bus.
①
②
③