Basic Electrical Installation Work

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. The sealing pot filled with sealing compound, which is pressed from one side only prevent air pockets forming, and the pot closed crimping home the sealing disc with crimping tool such as that shown Fig 7. not affected water, oil the cutting fluids used engineering and can withstand very high temperature or even fire. All excess magnesium oxide powder must wiped from the conduc- tors with clean cloth. The cable diameter small relation its current carrying capacity and should last indefinitely correctly installed because is made from inorganic materials. 14. This can achieved using a rotary stripper tool or, only few cables are terminated, the outer sheath can removed with side cutters, peeling off the cable simi- lar way peeling the skin from piece fruit with knife. Such assembly suitable for working tempera- tures 105°C. These characteristics make the cable ideal for Band emergency circuits, boiler-houses, furnaces, petrol stations and chemical plant installations. The conductors are not identified during the manufacturing process and so necessary identify them after the ends have been sealed.26 for conduit.5), see Table 14. reduce the risk dam- age the outer sheath during installation, cables should straightened and formed hammering with hide hammer block wood and a steel hammer.8.3 shows brass screw-on seal and gland assembly, which allows termination the cables standard switchgear and con- duit fittings.4. Connection cables can made directly motors, but absorb the vibrations 360° loop should made the cable just before the termina- tion. Cable ends must terminated with special seal prevent the entry of moisture. Figure 6. The cable can be work hardened over-handled over-manipulated. The cable supplied coils and should run off during installation and not spiralled off, described Fig.Basic Electrical Installation Work 318 The cable may laid directly the ground, ducts, cable tray or clipped directly structure. simple continuity polarity test, described later this chapter, can identify the conductors which are then sleeved identified with coloured markers. This makes the cop- per outer sheath stiff and may result fracture. When bending cables the radius the bend should not cause the cable become damaged and clips should provide adequate support (Regulation 522. When enough conductor has been revealed, the outer sheath must cut off square to facilitate the fitting the sealing pot, and this can done with ringing tool. excessive vibration expected the cable should termi- nated conduit through box and the final connection made flexible conduit. Other compounds powdered glass can increase the working temperature 250°C. The outer sheath the cable must not penetrated, otherwise moisture will enter the magne- sium oxide insulation and lower its resistance.5. The cable must prepared for termination removing the outer copper sheath reveal the copper conductors. This prevent moisture from penetrating the seal capillary action