Low cost digital lease lines can be used to increase the reliability and speed of SCADA communications. The cost to obtain these benefits is approximately 10%-40% more than an equivalently routed analog lease line. Digital lease lines are more reliable than analog lease line because digital data transmissions are less sensitive to impairments. Faster data rates also provide the data throughput to program remote facilities online from a central location. High speed lease lines, like 56.0 Kbps circuits, can be divided into separate data channels without the expense of purchasing a separate circuit. Also, modifications like changing channel data rates are easily implemented without the delays and expense of contacting the telephone company. The network reconfiguration option provides additional flexibility in managing and maintaining the network. By dialing into the phone system with a remote terminal, utility staff can rearrange segments to bypass a bad segment or recover from a disaster. As a result of the successful implementation of ADN by two utilities described in this paper, other water utilities may want to consider installing low cost digital lease lines for their SCADA communications.
| File Size : | 1
file |
| ISBN(s) : | 0898676347 |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 15 |
| Published : | 01/01/1992 |
