IEEE 575:2014 pdf free download

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IEEE 575:2014 pdf free download

IEEE 575:2014 pdf free download.IEEE Guide for Bonding Shields and Sheaths of Single-Conductor Power Cables Rated 5 kV through 500 kV.
In the design of special shcath-bonding arrangements, consideration must be g.cn to the lllowing aspects:
a) Cable sheaths on short transmission cable circuits and most distribution circuits are usually cxpcctcd to be nominally at ground potential. lIos%cver, in a specially bonded system the shicldsshcaths can havc apprcciahlc ohagcs with respect to ground and shields shcaihs should ncer bc assumed to he at ground potential. Appropnatc precautions must be taken to cnsurc that personnel are aware of the potential hazard and proper safety procedures. Consideration should be giben to cliective installation of appropriate barners, ammg devices, etc., as arrantcd by cpcctcd shicldshcath voltages.
b) Complete supprcsion of circulating shicldshcath currents may not always be possible because of practical difficulties in the choice of cable lengths and cable spacing. It is then necessary 10 calculate the residual sheath currents and asscs their cued on the cable rating.
d) The use of special bonding gibei rise to sheath overoltages during system transients and faults. and the magnitudes of thosc oenohagcs must be considered in the design of the cable system. For higher voltage systems. a shieldsheath voltage limiter will be generally needed and iii all cases consideration must be given to the coordination of the jacket insulanon levels, thc voltages to which the jacket will be subjected. and the characteristics of surge voltage protective devices.
C) Failure of a part of the jacket or of a sheath voltage limiter (SVL) can result in eccssivc shieldshcath currents and losscs and causc overheating of the cables. Consideration must therefore be given to the duty imposed on the shicldsheath voltage-limiting dc ice and to the monitoring and maintenance of the complete systems.
For single-conductor cable circuits carrying currents in excess of about 500 A, special bonding is often economically desirable as thc reduction in losses allows an appreciably smaller conductor Size to be used. Very often, employing special bonding will permit the usc of a single cable per phase installation where. othcrwssc, multiple cables per phase would he required with the use of solid bonding. There is no clear-cut load level at which special bonding should be introduced and the extra cost of the larger conductor cable or multiple cables per phase system needed liar a solidly bonded system must be weighed against the cost of the additional equipment and the maintenance cost ansing from the greater complexity of a specially bonded systent.