Demand-Diversity Factor Value Quick Reference
April 1, 2018 6 Comments
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Diversity Factor (NBC) |
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| Type of Load |
Type of Building |
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| Individual House Hold , Individual Dwelling of a Block | Small Shops, Stores, Offices & Business Premises | Small Hotels, Boarding Houses, etc | |
| Lighting | 66% of total current demand | 90% of total current demand | 75% of total current demand |
| Heating and power | 100% of total current demand up to 10 A+ 50 % of any current demand in excess of 10 A | 100% of full load of largest Appliance + 75% of Remaining appliances | 100% of full load of largest appliance+ 80% of second largest appliance + 60% of remaining appliances |
| Cooking appliances | 10 A +30 percent full load of connected cooking appliances in excess of 10 A + 6 A if socket-outlet incorporated in the unit |
100 % of full load of largest appliance + 80% of full load of second largest appliance + 60% of full load of Remaining appliances | 100 % of full load of largest appliance + 80 % of full load of second largest appliance + 60% of full load of Remaining appliances |
| Motors (other than lift motors which are subject to special consideration) | 100% of full load of largest Motor + 80% of full load of second largest motor | 100 % of full load of largest Motor + 50%of full load of remaining motors | |
| Water heater (instantaneous) | 100 % of full load of largest Appliance + 100%of full load of second largest appliance + 25 %of full load of remaining appliances | 100 % of full load of largest Appliance + 100%of full load of second largest appliance + 25 %of full load of remaining appliances | 100 % of full load of largest Appliance + 100%of full load of second largest appliance + 25 %of full load of remaining appliances |
| Water heater (thermostatically controlled) | No diversity | ||
| Standard arrangements of final circuits in accordance with good practice | 100 percent of the current demand of the largest circuit + 40 percent of the current demand of every other circuit | 100 percent of the current demand of the largest circuit + 50 percent of the current demand of every other circuit |
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| Socket outlets other than above and stationary equipment other than those listed above | 100% of the current demand of the largest point + 40%of the current demand of every other point | 100% of the current demand of the largest point+ 75 % of the current demand of every other point |
100%of the current demand of the largest point + 75%of the current demand of every point in main rooms (dining rooms, etc) + 40 % of the current demand of every other point |
| After calculating the electrical load on the above basis, an overall load factor of 70 to 90 percent is to be applied to arrive at the minimum capacity of substation. | |||
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Demand Factors (As Per Table 220.42 NEC) |
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| Type of Occupancy | Electrical Load | Demand Factor |
| Dwelling units | First 3000 VA | 100% |
| From 3001 to 120,000 VA | 35% | |
| Remainder over 120,000V A | 25% | |
| Hospitals | First 50,000 VA or less | 40% |
| Remainder over 50,000 VA | 20% | |
| Hotels and motels, including apartment houses without provision for cooking by tenants | First 20,000 VA | 50% |
| 20,001 VA to 100,000 VA | 40% | |
| Remainder over 100,000 VA | 30% | |
| Warehouses storage | First 12,500 VA | 100% |
| Remainder over 12,500 VA | 50% | |
| All others | Total volt-ampere | 100% |
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Non-dwelling Lighting Loads Demand Factors (As Per 220.44 NEC) |
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| Type of Occupancy | Electrical Load | Demand Factor |
| Non-dwelling Receptacle Loads | First 10KVA | 100% |
| Remainder over 10KVA | 50% | |
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Diversity (The Electricians Guide 5th Edition by John Whitfield) |
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| Type of final circuit | Type of premises | ||
| Households | Small shops, stores, offices | Hotels, guest houses | |
| Lighting | 66% total demand | 90% total demand | 75% total demand |
| Heating and power | 100% up to 10 A + 50% balance | 100%X + 75%(Y+Z) | 100%X + 80%Y + 60%Z |
| Cookers | 10 A + 30% balance + 5 A for socket | 100%X + 80%Y + 60%Z | 100%X + 80%Y + 60%Z |
| Motors (but not lifts) | 100%X + 80%Y + 60%Z | 100%X + 50%(Y+Z) | |
| Instantaneous water heaters | 100%X + 100%Y + 25%Z | 100%X + 100%Y + 25%Z | 100%X + 100%Y + 25%Z |
| Thermostatic water heaters | 100% | 100% | 100% |
| Floor warming installations | 100% | 100% | 100% |
| Thermal storage heating | 100% | 100% | 100% |
| Standard circuits | 100%X + 40%(Y+Z) | 100%X + 50%(Y+Z) | 100%X + 50%(Y+Z) |
| Sockets and stationary equip. | 100%X + 40%(Y+Z) | 100%X + 75%(Y+Z) | 100%X + 75%Y + 40%Z |
| X = the full load current of the largest appliance or circuit | |||
| Y = the full load current of the second largest appliance or circuit | |||
| Z = the full load current of the remaining appliances or circuits | |||
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Diversity factor for Building (Horizon Power) |
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| No of customer | Diversity factor |
| 1 | 3 |
| 2 | 2.57 |
| 3 | 2.2 |
| 4 | 2 |
| 5 | 1.89 |
| 6 | 1.8 |
| 7 | 1.74 |
| 8 | 1.71 |
| 9 | 1.69 |
| 10 | 1.64 |
| 11 | 1.61 |
| 12 To 14 | 1.57 |
| 15 To 17 | 1.5 |
| 18 To 20 | 1.46 |
| 21 To 23 | 1.42 |
| 24 to 26 | 1.4 |
| 27 To 29 | 1.38 |
| 30 To 59 | 1.37 |
| ≥60 | 1 |
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Demand Factor (The Electricians Guide Fifth Edition) by John Whitfield) |
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| Area | Demand Factor |
| Office / School | 40% |
| Technical Blocks / Hospital | 50% |
| Air Port / Banks / Department Store / Shopping Center / Public Place | 60% |
| Restaurants / Factories (for 8 Hours Shifts) | 70% |
| Workshops / Factories (for 24 Hours Shifts) | 80% |
| Arc Furnace | 90 % TO 100% |
| Arc Welding | 20 % TO 50% |
| Compressor | 20 % TO 50% |
| Conveyor Crane | 90 % TO 100% |
| Had tool | 20 % TO 40% |
| Paper Mills | 50 % TO 70% |
| Induction Furnace | 80 % TO 100% |
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Demand Factor As per No of Appliances |
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| No of Appliances | (A) Less than 3.5 KW | (B) 3.5 KW to 8.5 KW | (C) Less 12 KW |
| 1 | 80% | 80% | 8% |
| 2 | 75% | 655 | 11% |
| 3 | 70% | 55% | 14% |
| 4 | 66% | 50% | 17% |
| 5 | 62% | 45% | 20% |
| 6 | 59% | 43% | 21% |
| 7 | 56% | 36% | 22% |
| 8 | 53% | 35% | 23% |
| 9 | 51% | 34% | 24% |
| 10 | 49% | 32% | 25% |
| 11 | 47% | 32% | 26% |
| 12 | 45% | 32% | 27% |
| 13 | 43% | 32% | 28% |
| 14 | 41% | 32% | 29% |
| 15 | 40% | 32% | 30% |
| 16 | 39% | 28% | 31% |
| 17 | 38% | 28% | 32% |
| 18 | 37% | 28% | 33% |
| 19 | 36% | 28% | 34% |
| 20 | 35% | 28% | 35% |
| 21 | 34% | 26% | 36% |
| 22 | 33% | 26% | 37% |
| 23 | 325 | 26% | 38% |
| 24 | 31% | 26% | 39% |
| 25 | 30% | 26% | 40% |
| 26 To 30 | 30% | 24% | 15KW+1KW for Each |
| 31 To 40 | 30% | 22% | |
| 41 To 50 | 30% | 20% | 25KW+0.75KW for Each
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| 51 To 60 | 30% | 18% | |
| More Than 60 | 30% | 16% | |
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Lighting Demand for Building (As per NBC) |
| Lighting demand for buildings should be considered as per type of building. |
| Where nothing is specified, for lighting demand of any type of building a maximum of 13 W/m2 of all built-up areas including balconies. |
| Covered parking areas may be considered at 3.23 W/m2 including balconies, service areas, corridors, etc, may be considered with very basic diversity of 80 % to 100 %. |
| Power requirements shall be considered at least 55 W/m2 with an overall diversity not exceeding 50 %. These shall be excluding defined loads such as lifts, plumbing system, fire fighting systems, ventilation requirement, etc. |
JIGNESH PARMAR
Dear jignesh
the electrical articles what are posted is very useful and easy to understand.but i want buy yours electrical pdf book so guide me how to buy.
THANKS & REGARDS
ABDULLAH
Very Handy and Great appreciable Job done.
Thank you!
Thanks Jignesh.
For sharing very very useful notes. Could you please define the term “Current Demand”?
It will be very helpful if a example of load calculations on the basis of information sent by you is made available to us.
Thanks again
Hi Mr.Jignesh,
I am an Electrical Engineer in profession and working in the industry for 4 years. I need your kind advise for a practical problem I am facing. one of our Printing plant have 03 No of sub panel boards which are parallel. Each has several 3ph RCCB(40A,100mA). One specific RCCB from each sub panel getting tripped at once. but just after that we can switched on and work for 10 min and again tripped.these are connected to printing machines which are rotating itself by a motor. I couldnt find any fault there. When I check the harmonics from the DB analyser I noticed that the Nuetral harmonics level is about 187%. Please advice.
B/R Asanka Dilhari(BSc.Eng, Hons) Elec. Eng Jay Jay Mills Lanka (Pvt) Ltd A6, SEPZ Avissawella Sri Lanka
On Sun, Apr 1, 2018 at 5:51 PM, Electrical Notes & Articles wrote:
> Jignesh.Parmar posted: ” Diversity Factor (NBC) Type of Load Type of > Building Individual House Hold , Individual Dwelling of a Block Small > Shops, Stores, Offices & Business Premises Small Hotels, Boarding Houses, > etc Lighting 66% of total current demand 90%” >
THANKS FOR THE POST