Estimation of Electrical Wiring Multi Choice Questions & Answers

Estimation of Electrical Wiring Multi Choice Questions & Answers Points : estimation of electrical wiring multi choice questions and answers, estimation of electrical wiring mcqs, objective Multi Choice Questions & Answers

1. In bath rooms, all non-electrical metal work including must be bonded together and earthed.
   (a) Bath tubs
   (b) Water pipes
   (c) Sinks
   (d) All of above
2. Do not exceed per circuit
   (a) 800 watts
   (b) 10 lights or fans
   (c) 15 lights
   (d) All of above
3. Do not exceed per circuit - numbers of plug points for power circuit.
   (a) 2
   (b) 3
   (c) 4
   (d) 1
4. Use heavily insulated, flexible cables for _______ appliances.
   (a) Domestic & Commercial
   (b) Industrial
   (c) Commercial
   (d) Domestic

Estimation of Electrical Wiring True & False

Estimation of Electrical Wiring True and False Points : estimation of electrical wiring true and false estimation of electrical wiring objective True & False

1. Anyhow material handling charges should not be more than 5% (max.) of material cost. (T)
2. Overhead charges will generally be assumed as 10% to 25% of the total cost. (F)
3. In large installations, tool charges aren’t be included. (F)

Estimation of Electrical Wiring blanks

Estimation of Electrical Wiring blanks: Points : estimation of electrical wiring fill in the blanks, estimation of electrical wiring objective Fill in the blanks

1. Length of conduit required can be calculated by going through the plan of the building.
2. Allow 10% of total length for wastage in any system.
3. To calculate the length of wire, take the length of conduit after allowing wastage.

Estimation of Electrical Wiring Short Question and Answer

Estimation of Electrical Wiring Short Question and Answer Points : estimation of electrical wiring short question and answer Q # 1: What should be the resistance of earth continuity conductor in the completed installation? Answer: Circuit-breaker measured from the connection with the earth electrode to any points in the earth continuity conductor in the completed installation shall not exceed one ohm. Q # 2: What should be the estimate of length of wire for wiring? Answer: The length of wire can be taken as 2.5 times the length of conduit for looping system and 2 times for junction box system. Q # 3: What should be the estimate of length of wire for switch boxes? Answer: The length of the looping wire etc. in switch boxes shall not be lesser than 0.5 times of the height of the box itself.

Power Wiring Installations

Power Wiring Installations Points : power wiring installations, electrical power wiring installations

1. I.E.E. rules Nos. 22, 50, 51 are to be satisfied,
2. Wiring is to be installed either in surface conduits system or recessed conduit system.
3. Earth wire of 8 S.W.G. must run along the pipes.

Points To Be Considered While Preparing The Estimate

Points To Be Considered While Preparing The Estimate of Electrical Wiring Points : points to be considered while preparing the estimate, building wiring estimating & costing, estimate the installation of an electrical distribution, electrical design and estimation Points To Be Considered While Preparing the Estimate

1. Length of conduit required can be calculated by going through the plan of the building.
2. Allow 10% of total length for wastage in any system.
3. To calculate the length of wire, take the length of conduit after allowing wastage.
4. The length of wire can be taken as 2.5 times the length of conduit for looping system and 2 times for junction box system.

Fans and Exhaust Fans

Fans and Exhaust Fans Points : fans and exhaust fans, exhaust fans, testing of installation, insulation resistance test, testing of earth continuity path, earthed electrode resistance test Fans and Exhaust Fans Fans The fans shall be suspended from hooks or shackles by means of suspension rods. Rubber insulators (shackle) shall be provided between the hooks and suspension rods. There shall be no joints in the suspension rod. The canopies on top of the suspension rod shall hide the suspension. The lead-in-wire from the ceiling rose shall be of 1.5 mm2 size and shall be protected from abrasion. The fan blades shall be kept at least 2.75 metres above the floor unless specified otherwise.

Miniature Circuit Breakers

Miniature Circuit Breakers Points : miniature circuit breakers, distribution boards Miniature Circuit Breakers The current limiting miniature circuit breakers shall be I.S.I. marked of category M 91M 3 conforming to International standards of IEC: 8828-1978, BS-3871 part 1 and VDE-0641.

(i) Standard: “Standard KOPP” brand from 0.5 A to 63A
M 9 SP, SPN, DP, TP, TPN (four poles).

(ii) M.D.S.: “Load Konkatk” brand S 210-series, from

Switch (Panel) Boards

Switch (Panel) Boards Points : switch (panel) boards, rising mains The L.T Switch (Panel) Boards shall be factory fabricated and of the approved manufacturer. The switch board shall be fixed such that there shall be a clear space of either less than 230 mm or more than 762 mm in width behind the switch board measured from the farthest outstanding part of any attachment of conductor and more than 1000 mm in width in front of the switch board. There shall be a passage way from either end, both in front of or behind the switch board, clear to a height of at least 1829 mm.

No apparatus shall project beyond and edge of the panel. No switch body shall be mounted within 25 mm of any edge of the panel and no holes, either than meant for fixing the panel shall be drilled within 13 mm of the edge of the panel. The various live parts shall be effectively screened by barriers of non-hygroscopic, non-inflammable insulating material or shall be so spaced that an arc cannot be maintained between such parts and earth. All items of switch gears shall be readily accessible and all connections, including those to instruments and apparatus, easily traceable. The switch shall be as arranged that fuses are not “alive” when the switch is in the “Off’ position. No fuse other than those in instruments circuit shall be fixed at the back or behind a switch board, panel or frame.

Protection of Building Against Lightning

Protection of Building Against Lightning Points : protection of building against lightning, zone of protection, component parts and their installations, air terminations, down conductors, earth termination, earth electrodes , completion report General The protection of building against lightning shall generally and those of special structures like livestock in fields, structures for highly combustible materials etc. shall strictly be done in accordance with I S 2309-1969. For the purpose of protection of buildings against lightning both the vertical and horizontal conductors may be used as air terminations depending upon the type of building to be protected. Horizontal air terminations may be used in buildings with flat roof extending over a large area such as R.C.C. framed structure, multistoried buildings etc. Vertical air terminations may be used in buildings having towers and domes etc. A system of both vertical and horizontal conductors might be necessary for protection of bigger buildings. The materials of lighting protective system shall be copper or galvanized steel as specified. Brief specifications are described here below:

Overhead Electric Lines and Street Lights

Overhead Electric Lines and Street Lights Points : overhead electric lines and street lights, poles, cross arms, insulators, stay set, struts, conductors, lightning arrestors, insulators, stay set, struts, conductors, lightning arrestors, painting of poles, completion report, type of earth electrodes, pipe earth electrode, watering arrangement, artificial treatment of soil, earthing lead, protection of earthing lead, completion report Poles Overhead lines shall be supported on steel tubular poles or steel rail poles. The steel tubular poles shall be of seamless / swaged and welded type and shall be in three stepped sections. Normally one sixth of the length of the pole shall be embedded in the ground. This length of the poles shall be coated with black bituminous paint, both internally and externally. The remaining portion of the pole shall be painted with one coat on its external surface. The pole shall be complete with .a cap and base plate. Steel tubular / steel rail poles shall be fixed over 1.5 cm thick bed of 1:3:6 (1 cement: 3 coarse sand : 6 graded stone aggregate of 40 mm normal size) foundation with not less than 20 cm thick layer of cement concrete all round the foundation being continued up to 30 cm above ground level and tapered suitably into a collar. The excavated portion shall be filled back with earth and consolidated properly using water, if necessary. The cement concrete foundation shall be cured properly using moist gunny bags before leading the pole.

Under Ground Electric Cables

Under Ground Electric Cables Points : under ground electric cables, testing, cable conductor, handling of cables, cable route, laying of cables, laying in pipes / closed ducts, laying on surface, cable identification tag, completion report Testing The cable shall be tested for continuity and insulation between conductors and conductor and earth before and after installation. Test results shall be submitted in the proforma given in Appendix 1. Cable Conductor The cable shall have either solid or stranded aluminum conductor and shall be P.V.C. insulated and P.V.C. sheathed and l.S.I. certified.

The cables may be armoured or unarmoured. Unarmoured cables may used only when the runs are short and the cables are laid in pipes or closed masonry trenched or protected and secured enclosures. Single core cables armoured with steel wire or tape shall not be used for alternating current supply. Selection of Cables: The final current carrying capacity of the cable, after allowing for derating, shall not be less than the current ills required to carry. The current carrying capacity of P.V.C. insulated and P.V.C. sheathed cables and the derating factors are given in Appendix 5.

Concealed (Recessed) Conduit Wiring System

Concealed (Recessed) Conduit Wiring System Points : concealed (recessed) conduit wiring system, selection of-size conductors, capacity of sub-circuits, passing through walls and floors, fittings and accessories, socket outlet and plugs, laying of conduit in slab, main switches and switch boards, main and branch distribution boards, boards for mounting switch gear, hinged type metal boards, hinged type wooden boards, fixed type wooden board, lighting fittings, fittings wire, fluorescent tube fittings, high pressure mercury / sodium vapour lamps, lamp holders, outdoor fittings, height of fittings This system of wiring shall comply with all the requirement described above under ‘surface conduit system’ and, in addition, conform to the requirements described here under. The conduit shall be fixed in position by means of staples not more than 60 cm apart by making a chase in the wall. The conduit shall be fixed so that its top is 6 mm below the surface of wall. The chase shall be ample of dimension to permit the conduit to be fixed properly and shall be made neatly in the wall. The chase shall be filled up neatly erection of conduit and finished to original finish and color of the wall.

All curves shall be maintained by bending the conduit pipe itself with a long radius or by solid type long bends. Fixing of standard bends elbows shall be avoided. Fish steel wire of 16 SWG size shall be provided along with laying of conduit to facilitate drawing of wires in the conduit.

Suitable inspection boxes shall be mounted, flush with the wall ceiling,, at suitable intervals to facilitate drawing and removal of wires. Inspection boxes shall be of cast iron or sheet steel. Suitable ventilating holes shall be provided in the covers of the inspection boxes.

The outlet boxes shall be same as for surface conduit system and shall be mounted flush with the wall ceiling.

Miscellaneous Electrical Tools and Supplies C Clamps

Miscellaneous Electrical Tools and Supplies C Clamps Points : Miscellaneous Electrical Tools and Supplies C Clamps, Ordinary 3 in. malleable C clamps are very useful for clamping large sets of plans to end of the estimating table. This reduces the space taken up by plans to a minimum, and as the sheets are turned over, their weight will not pull the set of the table. It is often necessary to turn sheets back and fourth for reference purposes, it is much easier to handle then with clamps on the table than it is to have to fold them under. Pencils and Crayons Colored pencils are also indispensable for checking materials taken of the plans. There are all kinds of colored pencils on the marked. Some of them are not suitable for estimating because the markings are too hard to remove from the plans. One should select pencils that will leave a plain mark without too much pressure. The markings should also be such that they can be easily removed what an easier .or a cleaning fluid. It is well for an estimator to form the habit of using a set color scheme for checking, such as orange for lighting, red for power, yellow for signals. The same color scheme can be used making notes on the plans, underscoring notes already overlooked when it comes time for the take off.

Estimating of Electrical Wiring

Estimating of Electrical Wiring Points : Estimating of Electrical Wiring, What Is Estimating Electrical Wiring, Steps of Form and Estimate Are, Estimating and Its Importance, Estimating of Electrical Wiring Tools, The Map Measure, Tape Measures, The Tally What Is Estimating Estimating means to determine the quantities of various items required to execute a job and to assess the cost of the execution. The estimator keeping in view the requirements arrived at during initial planning, chalk out a list of items and quantities. The cost is determined by him by consulting the price catalogue and schedule of labour rates. Steps of Form and Estimate Are (1) Chalk out a list of items and quantities required.
(2) Consult the rate catalogues for pricing the various items.
(3) Assess the exact number of workmen required to complete the job and after consulting the schedule of labour rates add the labour cost to the estimate under preparation. It should be noted that number of workmen required is dependent upon the time limit fixed to complete the service.
(4) Add supervision charges and executor’s profit.
(5) In case of Govt. Organization, where the work is to be executed the contractor, the tenders are floated only after correctly specifying the description of each item, to avoid any misunderstanding while execution.

Electrical Wiring Planning Short Questions with Answers

Electrical Wiring Planning Short Questions with Answers Points : electrical wiring planning short questions with answers Q # 01: What are the steps of consideration at design stage of installation? Answer : Every design must consider the following steps Flexibility: Depending upon the type of building electrical system must be designed to provide required flexibility in distribution, distribution panels and circuits. Accessibility: Every electrical system should rate high in accessibility. In its final form, design of the system must provide ease of access to equipment for maintenance and repair and for any possible extensions, modifications or alterations in the system. Reliability: Due to the nature of activities, a building continuity of electrical supply and over-all reliability of the wiring system should be ensured. But in many industrial plants, hospitals and buildings with essential equipment electrically powered, standby power plants or multiple services must be used for absolute reliability of supply.

Diversity and Sub-Main Calculations

Diversity and Sub-Main Calculations Points : diversity and sub-main calculations, diversity, use diversity table, use a power load for per socket outlet, use a base load per ring circuit and try to anticipate other heavy loads Having detailed the final circuits we have now to consider how each of these fuse-boards are to be supplied. Diversity Table lB (copy below) within the lEE On-Site Guide, Appendix 1, Allowances for Diversity gives guidance with regard to typical allowances for diversity which may or may not be applied as you feel appropriate. The lighting for example is reasonably simple.

Summary of General Guidelines -Circuit Design

Summary of General Guidelines -Circuit Design Points : Summary of General Guidelines -Circuit Design, Lighting Circuits, Power Circuits Lighting Circuits 1. Unless the accessories being used are designed to accept wiring larger than 1.5 mm, (or you intend to use connector/junction boxes at each luminaire location which will accept larger cable sizes), or unless the sub-main cables are very short (so that they have no effective voltage losses) then aim to fuse circuits at 5-6 Ampere and load the protective device to around 1000 VA (5A), 1200 VA (6A) for normal circuits and 500- 600 VA for essential or ‘means of escape’ circuits.
2. Remember to use the ‘1.8’ factor for discharge lighting.
3. Keep a circuit to a maximum length of 25 metres if fully loaded.

Practical Advice on Choice of Electric Cables

Practical Advice on Choice of Electric Cables Points : Practical Advice on Choice of Electric Cables, Example of Choice of a electric Cable Advice on Choice of Electric Cables Fig sets out in a convenient manner, recommended cables for most conditions of installation. To find the correct range of cables for a particular method of installation, look up in the first column the method that will be used, and opposite that will be found’ a range recommended V.R.I. and P.VC., insulated cables manufacture. All these cables are illustrated in Figs. Together with their respective reference numbers. Having previously determined the size of conductor, number of cores, voltage grade and type of insulation, the cable best suited for- the job can then easily be selected and ordered.

Earth Electrodes

Earth Electrodes Points : Earth Electrodes, Earth Electrodes, Sizes and Grades of Cables, Size of Main and Sub-main Cables, Size of Final Sub-Circuit Cables, Single or Multi-Core Cables, Which Voltage Grade to Use? The following types of earth electrode are recognized for the purpose of these Regulations:
• Earth rods or pipes,
• Earth tapes or wires,
• Plates,
• Electrodes embedded in foundations.
• Metallic reinforcement of concrete.
• Metallic pipe systems, where not precluded by Regulations 542—14 and 542 — 15.