GE DS200PCCAG7A Output expansion module

The second remedy to a violation of the 8-in-16 rule is to add additional cable to the bus such that the rule is no longer violated (figure 9). It is important to ensure that the maximum bus length (130 meters of 22AWG/0.65mm Level IV twisted pair) is not exceeded by the additional cable. Due to the complex interactions between the bus and the transceivers with regard to reflections and transmission line delays, it is not possible to substitute an LC network in lieu of the additional cable to resolve this rule violation.Twisted pair network segments require termination for proper data transmission performance. For doubly terminated bus topologies, a termination must reside at both endpoints of the bus. The terminations required for TP/XF-78, TP/XF-78F, and TP/XF-1250 segments are shown in figure 5.5.

RS-485 Grounding 

Proper operation of the transmit and receive circuits requires the presence of a signal return path between the circuit grounds of the equipment at each end of the interconnection. The circuit reference may be established by a third conductor connecting the common leads of devices, or it may be provided by connections in each to an earth reference. Where the circuit reference is provided by a third conductor, the connection between circuit common and the third conductor must contain some resistance (i.e., 100 Ohms) to limit circulating current when other ground connections are provided for safety

Cable Termination - TP-RS485 Segment 

TP-RS485 twisted pair network segments are wired in a doubly terminated bus topology, and a termination must reside at both endpoints of the bus. The termination network shown in Figure 5.5 may be used to terminate a TP-RS485 segment. Alternately, each end of a TP-RS485 segment can be terminated with a 120 Ohm, 5% resistor (a total of two resistors, one at each end of the bus).

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----------------------Ruichang Mingsheng Automation Equipment Co., Ltd----------------------

PLC module, programmable controller, CPU module, IO module, DO module, AI module, DI module

Network communication module,

Ethernet module, motion control module, analog input module, analog output module, digital input module, digital output

Module, redundancy module, power module, relay output module, relay input module, processor module