Electrical Abstract-National Electrical Code-NEC
August 19, 2014 17 Comments
| Capacitor Bank for Power Supply Voltage | |
| System Voltage | Minimum rating of capacitor bank |
| 3.3 KV , 6.6KV | 75 Kvar |
| 11 KV | 200 Kvar |
| 22 KV | 400 Kvar |
| 33 KV | 600 Kvar |
| Capacities of PVC conduits | ||||
| Nominal conductor Size mm | 16 mm | 20 mm | 25 mm | 32 mm |
| Number of Cables (maximum) | ||||
| 1.0 | 6 | 5 | 19 | 30 |
| 1.5 | 5 | 4 | 15 | 24 |
| 2.5 | 3 | 3 | 11 | 17 |
| 4 | 2 | 2 | 8 | 13 |
| 6 | 2 | – | 6 | 10 |
| 10 | – | – | 4 | 6 |
| 16 | – | – | 3 | 4 |
| 25 | – | – | 2 | 3 |
| 35 | – | – | – | 2 |
| System Highest and Lower Voltage | ||
| Ref: NEC(India) :2011 | ||
| System Voltage | Highest Voltage | Lowest Voltage |
| 240 V | 264 V | 216 V |
| 415 V | 457 V | 374 V |
| 3.3 kV | 3.6 kV | 3.0 kV |
| 6.6 kV | 7.2 kV | 6.0 kV |
| 11 kV | 12 kV | 10 kV |
| 22 kV | 24 kV | 20 kV |
| 33 kV | 36 kV | 30 kV |
| 66 kV | 72.5 kV | 60 kV |
| 66 kV | 72.5 kV | 60 kV |
| 132 kV | 145 kV | 120 kV |
| 220 | kV 245 kV | 200 kV |
| 400 kV | 420 kV | 380 kV |
| Number of Points for Dwelling Unit | ||||||
| Ref: NEC(India) :2011 | ||||||
| No. | Description | Area for the Main Dwelling Unit (m2) | ||||
| 35 mm2 | 45 mm2 | 55 mm2 | 85 mm2 | 140 mm2 | ||
| 1 | Light points | 7 No | 8 No | 10 No | 12 No | 17 No |
| 2 | Ceiling fans Pont | 2 No | 3 No | 4 No | 5 No | 7 No |
| 3 | Ceiling fans No’s | 2 No | 2 No | 3 No | 4 No | 5 No |
| 4 | 6A Socket outlets | 2 No | 3 No | 4No | 5 No | 7 No |
| 5 | 16A Socket outlets | – | 1 No | 2 No | 3 No | 4No |
| 6 | Call-bell (buzzer) | – | – | 1 No | 1 No | 1 No |
| Recommended Schedule of Socket-Outlets | ||
| Ref: NEC(India) :2011 | ||
| Description | Number of Socket | |
| 6A Socket | 16A Socket | |
| Bedroom | 2 | 1 |
| Living room | 2 | 2 |
| Kitchen | 1 | 2 |
| Dining room | 2 | 1 |
| Garage | 1 | 1 |
| For refrigerator | – | 1 |
| For air-conditioner | – | 1 for each |
| Verandah | 1 per 10mter2 | 1 |
| Bathroom | 1 | 1 |
| Power requirements of the building | ||
| Ref: NEC(India) :2011 | ||
| Part of ElectricalInstallation | Part of the Total Power Requirement in % | DiversityFactor |
| Ventilation, heating (air-conditioning) | 45% | 1.0 |
| Power plant (drives) | 52% | 0.65 |
| Lighting | 30% | 0.95 |
| Lifts | 20% | 1.0 |
| Kitchen | 10% | 0.6 |
| Laundry | 5% | 0.6 |
| Lift Car Speed | ||
| Ref: NEC(India) :2011 | ||
| Occupancy | No. of Floors Served | Car Speed m/s |
| Office building | 4 to 5 | 0.5 to 0.75 m/sec |
| Office building | 6 to 12 | 0.75 to 1.5 m/sec |
| Shops and departmental stores | 13 to 20 | More than 1.5 m/sec |
| Passenger lifts for low and medium lodging houses | – | 0.5 m/sec |
| Hotels | 4 to 5 | 0.5 to 0.75 m/sec |
| Normal load carrying lifts | – | 2.0 to 2.5 m/sec |
| Hospital passenger Lift | 4 to 5 | 0.5 to 0.75 m/sec |
| Hospital passenger Lift | 13 to 20 | More than 1.5 m/sec |
| Hospital bed lifts (Short travel lifts insmall hospitals) | – | 0.25 m/sec |
| Hospital bed lifts (Normal) | – | 0.5 m/sec |
| Hospital bed lifts (Long travel lifts inGeneral hospitals) | 0.6 to 1.5 m/sec | |
| Capacitor Ratings at Rated Voltage | ||||||
| Ref: NEC(India) :2011 | ||||||
| Motor Rating(Kw) | Capacitor Rating in kVAR for Motor Speed | |||||
| 3 000rev/min | 1 500rev/min | 1 000rev/min | 750rev/min | 600rev/min | 500rev/min | |
| 2.25 | 1 | 1 | 1.5 | 2 | 2.5 | 2.5 |
| 3.7 | 2 | 2 | 2.5 | 3.5 | 4 | 4 |
| 5.7 | 2 | 3 | 3.5 | 4.5 | 5 | 5.5 |
| 7.5 | 3 | 4 | 4.5 | 5.5 | 6 | 6.5 |
| 11.2 | 4 | 5 | 6 | 7.5 | 8.5 | 9 |
| 15 | 5 | 6 | 7 | 9 | 11 | 12 |
| 18.7 | 6 | 7 | 9 | 10.5 | 13 | 14.5 |
| 22.5 | 7 | 8 | 10 | 12 | 15 | 17 |
| 37 | 11 | 12.5 | 16 | 18 | 23 | 25 |
| 57 | 16 | 17 | 21 | 23 | 29 | 32 |
| 75 | 21 | 23 | 26 | 28 | 35 | 40 |
| 102 | 31 | 33 | 36 | 38 | 45 | 55 |
| 150 | 40 | 42 | 45 | 47 | 60 | 67 |
| 187 | 46 | 50 | 53 | 55 | 68 | 76 |
| :Maximum Current Demand for Motor: | ||
| Ref: NEC(India) :2011 | ||
| Nature of supply | Size of installation | Maximum current demand |
| Single phaseor Three phase | Up to and including 0.75 kW | Six times the full load current |
| Above 0.75 kW and up to 7.5 kW | Three times the full load current | |
| Above 7.5 kW up to and up to11 kW | Two times the full load current | |
| Above 11 kW | One and half times the full load current | |
| Rated Basic Insulation Level (BIL) | |
| Ref: NEC(India) :2011 | |
| Nominal System Voltage (kV) | Rated BIL (kVp) |
| 33 KV | 170 |
| 22 KV | 125 |
| 11 KV | 75 |
| 6.6 KV | 60 |
| 3.3 KV | 40 |
| Illumination Level | |
| Ref: NEC(India) :2011 | |
| Location | Illumination Level (Lux) |
| Residence | |
| Entrance / Hallways | 100 |
| Living room | 300 |
| Dining Room | 150 |
| Bed Room (General) | 300 |
| Bed Room (Dressing , Bed Heads) | 200 |
| Kitchen | 200 |
| Kitchen sink | 300 |
| Bathroom | 100 |
| Sewing | 700 |
| Workshop | 200 |
| Staircase | 100 |
| Garage | 70 |
| Study Room | 300 |
| Office Building | |
| Entrance hall / Reception | 150 |
| Conference Room / Executive Office | 300 |
| General Office Space | 300 |
| Business Machinery Operation | 450 |
| Drawing Office | 450 |
| Corridors | 70 |
| Stairs | 100 |
| Lift landing | 150 |
| Hospital Building | |
| Reception & Waiting | 150 |
| General ward | 100 |
| Bed Side | 150 |
| Toilet | 70 |
| Stairs | 100 |
| Operation Theatre (General) | 300 |
| Operation Theatre (Operation Table) | Special |
| Laboratories | 300 |
| Radiology | 100 |
| Causality | 150 |
| Dispensaries | 300 |
| Laundry | 200 |
| Dry Cleaning | 200 |
| Ironing | 300 |
| General Office | 450 |
| Kitchen | 200 |
| Assembly & Concert Halls | |
| Foyers | 100 to 150 |
| Auditoria | 100 to 150 |
| Platform | 450 |
| Corridors | 70 |
| Stairs | 100 |
| Cinema Halls | |
| Foyers | 150 |
| Auditoria | 50 |
| Corridors | 70 |
| Stairs | 100 |
| Theatres | |
| Foyers | 150 |
| Auditoria | 70 |
| Corridors | 70 |
| Stairs | 100 |
| School / College Building | |
| Assembly Halls | |
| General | 150 |
| Examination center | 300 |
| Platform | 300 |
| Classes | |
| Desktop | 300 |
| Blackboard | 200 to 300 |
| Libraries | |
| Shelves | 70 to 150 |
| Reading Room | 150 to 300 |
| Reading Table | 300 to 700 |
| Cataloguing | 150 to 300 |
| General | |
| Office | 300 |
| Staff Room | 150 |
| Corridors | 70 |
| Stairs | 100 |
| Lamp’s Lumen Data | ||
| Rating (Watt) | Life (Hours) | Initial Lumens |
| Incandescent Lamp | ||
| 60 | 1000 | 870 |
| 100 | 750 | 1750 |
| 150 | 2000 | 1740 |
| 200 | 2000 | 2300 |
| 500 | 2000 | 6500 |
| Fluorescent Lamp | ||
| 18 | 7000 | 1120 |
| 20 | 7000 | 1020 |
| 36 | 7000 | 2800 |
| 40 | 7000 | 2700 |
| 2X40 | 7000 | 4000 |
| Compact Fluorescent Lamp | ||
| 5 | 10000 | 220 |
| 7 | 7000 | 380 |
| 11 | 7000 | 560 |
| 13 | 7000 | 680 |
| 15 | 7000 | 810 |
| 18 | 7000 | 1050 |
| 23 | 7000 | 1500 |
| 26 | 7000 | 1800 |
| 32 | 7000 | 2400 |
| Mercury Vapour Lamp | ||
| 100 | 18000 | 3700 |
| 175 | 24000 | 8600 |
| 250 | 24000 | 12100 |
| 400 | 24000 | 22500 |
| 1000 | 24000 | 57000 |
| Metal Halide Lamp | ||
| 50 | 15000 | 3400 |
| 70 | 15000 | 5600 |
| 100 | 15000 | 9000 |
| 150 | 10000 | 13500 |
| 175 | 10000 | 15000 |
| 250 | 10000 | 20500 |
| 400 | 20000 | 36000 |
| 1000 | 12000 | 110000 |
| High Pressure Sodium Vapour Lamps | ||
| 35 | 16000 | 2250 |
| 50 | 24000 | 4000 |
| 70 | 24000 | 5800 |
| 100 | 24000 | 9500 |
| 150 | 24000 | 16000 |
| 250 | 24000 | 27500 |
| 400 | 24000 | 47500 |
| 1000 | 24000 | 140000 |
| Pulse Start Metal Halide Lamp | ||
| 50 | 15000 | 3400 |
| 70 | 15000 | 5600 |
| 100 | 15000 | 9000 |
| 150 | 15000 | 15000 |
| 175 | 15000 | 17500 |
| 200 | 15000 | 21000 |
| 250 | 15000 | 26300 |
| 320 | 20000 | 34000 |
| 400 | 20000 | 44000 |
| 450 | 20000 | 50000 |
| :Duty Type of Motor: | ||
| Ref: IS-325 | ||
| Duty Type Symbol | Duty Type | Application |
| S1 | Continuous Duty | Pumps, Bowers, Compressors, Fans |
| S2 | Short Time Duty | Siren, Flood relief Gates |
| S3 | Intermittent Periodic Duty | Valve, Actuators, Wire drawing machine |
| S4 | Intermittent Periodic Duty with starting | Hoist, Cranes, Lifts, Escalators |
| S5 | Intermittent Periodic Duty with starting / Breaking | Hoist, Cranes (with electronics Breaks), Rolling mills |
| S6 | Continuous Duty with Intermittent Periodic Duty | Machine tools, Conveyors |
| S7 | Continuous Duty with starting / Breaking | Machine tools, |
| S8 | Continuous Duty with periodic load changes | Pole Channing Applications |
| Type of Distribution System | |
| As per IEC 60364-3 | |
| Unearthed System | Earthed System |
| IT | TT / TN (TN-S,TN-C,TN-C-S) |
| First Letter (the neutral point in relation to earth):T= directly earthed neutral (from the French word Terre)I =unearthed or high impedance-earthed neutral (e.g. 2,000 Ω) | |
| Second letter (Exposed conductive parts of the electrical installation in relation to earth):T =directly earthed exposed conductive partsN =exposed conductive parts directly connected to the neutral conductor | |
JIGNESH PARMAR
Thanks sir
REGARDS
SUMIT SHARMA
+91-9654110362
Very useful information
Regards
Hemant Behl
An excellent add ups for electrical proffessionals.
Regards ,
Subrata Roy.
Dear sir,
This is excellent job you are doing
thanks and regards
Mohammed Mohsin Pasha
Hello sir
I want to take training from you.
Please provide me training for electrical designing.
Or guide me from where i have to take training.
thanks for notes. Is it possible that you can post about selection of de-tuned reactors for capacitor bank in detail [type formula as well theory associated with it and general practice during design?
excellent job indeed and thanks a lot
Dear Mr Jignesh
Could you please arrange one sample GA drawing of 66 kV substation, outdoor type and needs for my son project work.
Thanks and regards.
Paruchuri Venkateswara Rao KHAMMAM Phone: +919441248821
Dear Jignesh bhai,
Could you provide me download link for KSEI Handbook. I need to refer.
Dear sir thanks a lot
Dear Sir,
For UPS incomer how is the cable size is selected. Whether we require a isolation at output side or not
Regards
Ajay
Dear Sir,
lots of thanks.
give the formula to calculate the rquired to every quipments and design (ex. 45kw motor how many ratings c.b. and realy fuse and etc )
Dear sir my query s not related to the above posts… So I need a formula to find out fuel consumption of a diseal generator per hour in ( gallons or liters)….
Thank you very much ….
Great work done
Dear Sir, Kindly guide me for Specific testings and certificate for chemical earthings . We are manufacturer for the same items and we have sold more then 400 earthings in 5 year
We need to guide for approval for railway, Highway, CPWD and all other government department specifications for make our brand stables in India.
Thanks & Regards, Subhash Bochiwal On 19-Aug-2014 9:50 pm, “Electrical Notes & Articles” wrote:
> Jignesh.Parmar posted: ” Size of Cable on Secondary Side of Transformer > (11KV/433V) Ref: KSEI Handbook Rating of T/C (KVA) Primary current (Amp) > Secondary Current (Amp) Min. Size of Neutral Earthing Conductor (mm2) > Minimum Size of Cable (mm2) 63 ” >
Hi this article is very informative thanks for sharing keep up the good work