|
Diversity Factor (NBC) |
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| 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% 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 |
|
| 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) |
||
| 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 | |||
|
Diversity factor for Building (Horizon Power) |
|
| 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) |
|
| 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 |
|||
| 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
|
| 51 To 60 | 30% | 18% | |
| More Than 60 | 30% | 16% | |
|
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. |
April 01, 2018 at 05:51PM by Department of EEE, ADBU: https://ift.tt/2AyIRVT
