portermattcorp
Member
- Location
- Huntington Beach, CA USA
I need help with this one I believe I am doing it correctly but the answer is just not there. Can anyone assist me with this? I have checked all of the examples in the exam prep book but I is not helping. I will show you how I am calculating it. Can you tell me where I am going wrong? I am using 2008 NEC
1) Given a multi family dwelling with 16 units fed with a single 120/240 1 phase 3 wire system. Do not include any laundry or house loads. Each unit has 800 sq ft and each of the following.
6 KVA range
.4 KVA amp garbage disposal
2.2 KVA dish washer
4.4 KVA240 volt water heater
18 amp 120 volt Air conditioning unit
Using the standard method for load calculations the feeder load is???
800 sq ft X 3 = 2400 VA (220.12)
2 - 1500 VA small appliance circuit = 3000 VA (220.52 (A))
1 ? 1500 VA laundry circuit = 1500 VA (220.52 (B)) DO NOT INCLUDE AS DIRECTED
5400 VA General Lighting Load X 16 units
86400 VA
1st 3000 VA 100% = 3000 VA
2nd 83400 VA 35% x .35 = 29190 VA
32190 VA General Lighting Load Demand
Range 6000 VA (220.55) Column C 31 KW
31000 VA Range Load
Garbage Disposal .4 KVA = 400 VA
Dish Washer 2.2 KVA = 2200 VA
Water Heater 4.4 KVA - 4400
Total Connected Appliance Load = 7000 VA X 16 Units = 112000 VA multiply by .75 (220.53) = 84000 VA
84000 VA Appliance Calculated Load
A/C 18 amp X 120 volt = 2160 multiply by 16 units 34560 VA
34560 VA Total AC Load
32190 VA General Calculated Load
31000 VA Range Calculated Load
84000 VA Fixed Appliance Calculated Load
34560 VA AC Calculated Load
181750 VA - Total Connected Load/240Volt = 757.29 round up
ANSWER = 758 Amps total calculated load
1) Given a multi family dwelling with 16 units fed with a single 120/240 1 phase 3 wire system. Do not include any laundry or house loads. Each unit has 800 sq ft and each of the following.
6 KVA range
.4 KVA amp garbage disposal
2.2 KVA dish washer
4.4 KVA240 volt water heater
18 amp 120 volt Air conditioning unit
Using the standard method for load calculations the feeder load is???
800 sq ft X 3 = 2400 VA (220.12)
2 - 1500 VA small appliance circuit = 3000 VA (220.52 (A))
1 ? 1500 VA laundry circuit = 1500 VA (220.52 (B)) DO NOT INCLUDE AS DIRECTED
5400 VA General Lighting Load X 16 units
86400 VA
1st 3000 VA 100% = 3000 VA
2nd 83400 VA 35% x .35 = 29190 VA
32190 VA General Lighting Load Demand
Range 6000 VA (220.55) Column C 31 KW
31000 VA Range Load
Garbage Disposal .4 KVA = 400 VA
Dish Washer 2.2 KVA = 2200 VA
Water Heater 4.4 KVA - 4400
Total Connected Appliance Load = 7000 VA X 16 Units = 112000 VA multiply by .75 (220.53) = 84000 VA
84000 VA Appliance Calculated Load
A/C 18 amp X 120 volt = 2160 multiply by 16 units 34560 VA
34560 VA Total AC Load
32190 VA General Calculated Load
31000 VA Range Calculated Load
84000 VA Fixed Appliance Calculated Load
34560 VA AC Calculated Load
181750 VA - Total Connected Load/240Volt = 757.29 round up
ANSWER = 758 Amps total calculated load