I correctly answered 4 out of the 7 questions on the Washington State Administration Major Calculations exam this Saturday. I've taken this final section four times now. I'm using (to the best of my knowledge) the Mike Holt technique for standard multi family dwellings
Using Mike Holt's o2 electrical calculation book's multifamily dwelling unit standard load calcultaion I am unable to correctly answer the following question. For the integrity of the test I will maintain nearly the exact form of the question but use different numbers.
What is the feeder demand load on a 120/240 volt service for a 43 unit multifamily dwelling where each 750 square foot unit contains: There are no house or laundry loads to consider.
1 7.7 kw Range
1 14500 watt baseboard heater
1 .6 kva garbage disposal
1 1200 watt water heater
1 1400 watt dishwasher
43 units times 750 square feet times 3 va per square foot equals 96750va
two small appliance branch circuits in each of the 43 dwellings equals 129000va
There are no laundry loads to cinsidder so this is it for the general lighting and receptacles, small-appliance and laundry circuits
the total is 225750va
Using the 220.11 lighting demand factors in the 02 nec, dwelling unit lighting and receptacle loads are permitted to be 100% for the first 3000va 35% for the next 117000va and 25% for the remainder. This brings the lighting and receptacle load to 70387.5va
the total heat load is 623500va
The appliance load using the 220.17 appliance load demand factor is 103200va
There is no clothes dryer to consider.
The cooking equipment load using 220.19 collumn b is 66220va.
the total comes to 3597 amps
This hypothetical answer does not match the hypothetical test answers. If I'm doing something wrong I'd like to know. If there is a problem with the question I'd like the points.
Using Mike Holt's o2 electrical calculation book's multifamily dwelling unit standard load calcultaion I am unable to correctly answer the following question. For the integrity of the test I will maintain nearly the exact form of the question but use different numbers.
What is the feeder demand load on a 120/240 volt service for a 43 unit multifamily dwelling where each 750 square foot unit contains: There are no house or laundry loads to consider.
1 7.7 kw Range
1 14500 watt baseboard heater
1 .6 kva garbage disposal
1 1200 watt water heater
1 1400 watt dishwasher
43 units times 750 square feet times 3 va per square foot equals 96750va
two small appliance branch circuits in each of the 43 dwellings equals 129000va
There are no laundry loads to cinsidder so this is it for the general lighting and receptacles, small-appliance and laundry circuits
the total is 225750va
Using the 220.11 lighting demand factors in the 02 nec, dwelling unit lighting and receptacle loads are permitted to be 100% for the first 3000va 35% for the next 117000va and 25% for the remainder. This brings the lighting and receptacle load to 70387.5va
the total heat load is 623500va
The appliance load using the 220.17 appliance load demand factor is 103200va
There is no clothes dryer to consider.
The cooking equipment load using 220.19 collumn b is 66220va.
the total comes to 3597 amps
This hypothetical answer does not match the hypothetical test answers. If I'm doing something wrong I'd like to know. If there is a problem with the question I'd like the points.