Electrical Contracting News (ECN) August 2016 - Page 23

CABLE MANAGEMENT To better understand this point, it is worthwhile using the example of IP4X. This rating specifies that protection against a 1.0mm probe is required, but the cabling does not need safeguarding from the ingress of water. Therefore, IP4X may not be watertight, but it does guard against the entry of debris, which could compromise the safety of the cabling within. IP4X can also be reliably tested with a 1mm diameter probe without penetrating the trunking. Unlike the case of IPXXD rating, gaps that occur as a result of adjoining trunking do not need protection from solid particles. The letter ‘D’ added to the code indicates that safeguarding from access to hazardous parts with wire should be provided. Even though physical contact with hazardous elements contained in the trunking is not allowed during tests, the 1mm diameter probe demonstrates that an IPXXD rated system remains penetrable to wire. Therefore, it could be concluded that when an IP4X compliant system is specified and installed, a more robust provision is ensured and a more reliable approach achieved. However, the specification of which IP rating to use should be made at the discretion of the electrical contractor, as there are a number of key factors to take into account that could influence this decision. These include: • The level of protection required at the place of the installation. • Type of application. • The people who are likely to use or come into contact with the equipment. • The suitability of the enclosure for the intende ܚ[[\ۛY[ \H][ۜ‘][]T ٙ\Y\\ܛX[H[XH[[X[ۋ]\\[\HH[X[܂XYZ[T \Z[ٙ[HX\] H[\X^HYH[BX]][ۜXXY]HT \X[H]H]KY[[Z]Y˜\HXH[\\˂Y][ۘ[K\H[[][ۜš[HXX[H\YۙY[[X\ܚY\]ٝ[X[܂Y][ۘ[[[X[ۙ\XY[Y\ˈۜ\]Y[KH[[][ۂܘ[[YH\[[YX]\HB\]Z\YX\ܚY\[][\H]Z[XHH\X]ܜ\[\ˈ]\\\H[][XX[۝Xܜ]H\[HY[\][[[XX[T \X[XB۝Z[Y[\[\˂]\Y[\[HXBX[Y[Y[X\]ٙ\[H[ܙBXX[[XۛZX[]H’T \X[KX^HYۚYX[B[H\]X][ۋ^\[\B۝Z[Y[][ۜ[[\[[X]\Hٙ]K\[\[]\T X[ۋY][ۘ[X\ܚY\\H[\]Z\Y[\[\H\[H[و[\[[]܈ZY[B\[H]Yݙ\H[]Y[Y]]HYY܈Z[ܙYX\ܚY\ˈ\[\\]Y[[[[^\YHۛXY܂YX\[[[[][ۋ\H\HX\Y[Y\[XYZ[[\\[[HXHX[Y[Y[\[K[Y]’[H]XH۝Z[Y[][ۋB[Y]وHYXYXY[YH\[[™HH[]\HوH[\[[œ\[H\]Z\Y]\]XH\[]ZYHوH\B[[\[H][Y\ۈXX[BX[YX\YX\ܚY\ˈ\H\HX\Y[Y\[XYZ[[\\š[[HXHX[Y[Y[\[K\B[YH[\[]H\[H]Z[š]\X[X[ [[T \X[\[H[HۜY\XB]ZX\[[ܙHYXY[ [\[Y]و[[]XY]\T \X[HH[\Z[œ[\\Y\\]]\YX[BZ]Y܈]ٚ]ڙXˈ[^\[š[[][ۜ[XH۝Z[Y[\[\[H]ٚ]XH[\B\[[ۈH[[]\[XYB[XKH[[[[X]H]\H\[H[HXYH\X[B[[[\܈Y[^[]H\Bݙ\][\\]Z\Y ]Y[\Z[BX\\YܙK]]ٚ]XH[\[[]\]XY]\T YX][H[Xܙ[H]H\[”Y[][ۜ\H^Hܝ\ XYY\[[BX\\Y]HYY][’T ^HݚYH[[\˜[\XH[[Y\HۙY[H]B\[H[H\Y\]HY[\]Z\[Y[وB\[Y[][ۜˈ[XX[۝Xܜ\ۜXH܈BXYX][ۈ[[[][ۈقXH۝Z[Y[][ۜœ[HT ݙ\T\H[\܈\XXKX[YX\\[YZ\\ܝH[Y[X]YXT \X[B[Z\[KH\Y\]ݚYH[\X][ۜX\HY\XH’T ][\HXZ[H]]B۝X][ۈH\HZ[BX\[XY[Y\YX[›X]\X[[\ܝ[B\Z[XKYH[\X[XHX[Y[Y[][ۋ[XX[۝Xܜ&B[X][ۈۈ[HڙX[[^\HXY]H[][BXYX][ۋXY]H][ YXH\]Z[XHB^\X[YX\\ۈB[\X]H[[œ][ۈ]\Y\]B][\۸&]\Z\HBڙX8&\XY[Y\˂‚LXHX[Y[Y[8$Y]X˚[ ‚N ̌ M L‚