357
Misconception about communication speed.
The communication systems are built for various purposes and applications. Most people feel that faster
communication means better. In fact, this concept is not necessarily correct. The reason is that faster communication
speed relies on the higher communication quality to support, which also means that higher communication
construction costs may be required.
Therefore, the correct approach is to, in response to the needs, choose the appropriate communication speed,
consider moderate construction costs and pursue stable communication quality.
For the situations when the constructed system can communicate acceptably, but sometimes breaks or error occurs.
That results the unsmooth and delayed data transmission, there are several suggestions listed below:
A. Check whether the communication software is working properly, including whether the communication parameters
(such as the time-out period setting) are correct.
B. Reduce and improve on the interference from the surrounding environment. Specic practices include reducing
the carrier frequency of the inverter, setting appropriately the grounding system of inverters and a variety of power
equipment. Besides, can even add noise suppress devices to the power wire.
C. It is recommended to use RS-485 dedicated transmission cable if the general transmission line is currently used.
D. Rewire the communication cables that following the principle of keeping away from sources of interference.
Overall consideration for the communication quality:
When building a communication system, it is often necessary to connect a variety of devices with different brands
and which is the difcult part. Additionally, the impact of environmental factors makes it more complicated.
When constructing communication systems, users often ask questions such as how long can this communication
distance be, then how long will the communication distance be? Nothing is wrong to ask such questions, since only
the excellent communication quality can ensure smooth communication. However, there is no standard answer.
Too many factors impact the communication quality of a project, such as the quality of equipment, wiring quality, the
quality of the environment at the site, even software quality and so on.
The suggestions to improve the quality of communication are made as follows.
A. Equipment quality:
The isolated communication interface is denitely better than non-isolated communication interface. However, for
many cheap communication interface converters on the market, even their specications do not meet the
standard. They may work in a simple testing, but the communication quality is poor, so should avoid using them.
B. Wiring quality:
Each communication interface has its standard transmission cable. The user often uses inappropriate cables in
order to reduce costs. When the communication system begins to appear to be unstable, please replace the
standard transmission cable to enhance the communication quality.
C. The quality of the environment at the site:
When a high noise source at the work site affects the communication, this situation should be improved by
reducing noise interferences. If this cannot be changed, should consider changing the routes of wiring to keep
away from the noise source.
D. The quality of the software program:
The communication system is generally used as monitor of equipments. There are monitoring computer and
monitoring software at the monitoring center. There are possibilities for errors to occur during communication.
During the communication, there may have the possibility of error. Therefore, the ability of monitoring software
to handle errors is related to the stability of the entire system.
At the hardware part, the communication quality should be improved as much as possible to avoid communication
errors. When the occasional error occurs, the quality of the software can offer a correct treatment. Only
two-pronged approach can build a stable and reliable communication system.
To Next Page