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Do the following:

Divide the total
lighting load (from Home work 4.1) by 3. Punch in these loads under
the three bus load columns against the feeder circuit in power panel
schedule.
Find out the
loads (in watts) of all convenience outlet circuits (#2 - #8). Load
of one convenience outlet is 180 W.
Punch in the
above loads against their respective circuit nos. in the power panel
schedule.
Punch in the
loads in such a way that all the columns have approximately the same
load when you add up the column loads (within 10% of one another).
Find the water
heater load from equipment schedule. This is a 208 V, 1-phase equipment.
Divide this load equally into two parts and punch them under any two
columns against the relevant circuit number in the power panel schedule.
Find the HVAC
load from equipment schedule. This is a 208 V, 3-phase equipment. Divide
this load equally into three parts and punch them under all three columns
against the relevant circuit number in the power panel schedule.
Do the above
loading in such a way that total loads for all three columns in the
power panel schedule are within 10% of one another.
Quantify some
additional circuits as spares and spaces (equal to 50% of the poles
i.e. cells in which you have punched in loads in watts).
Add the above
to the total number of cells in which you have punched in loads in watts.
If the number is odd, add one more pole to make the number additional
circuits quantified in #8.
You can use
the number of circuits calculated in #9 as: (a) all spares, (b) all
spaces, or (3) some of them as spares, some of them as spaces.
Punch in the
loads of the spare circuits (use the load for 6 convenience outlets
as the total load for one spare circuit)
Distribute
the loads of the spare circuits equally among all the three bus load
columns in the power panel schedule.
No load is
required to be calculated for spaces, if any.
Show the circuit
breaker ratings for water heater circuit and HVAC circuit (look up <
electrical wiring information > on my web page)
Use 20 A circuit
breakers for spare circuits
Show the conductor
sizes for all circuits (look up <electrical wiring information>
on my web page)
Complete service
entry data

EQUIPMENT
SCHEDULE

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Symbol

General

Volts (V)

Current

Power

Circuit #

Conductor

Termination

Phase

  

description

 
 

rating (A)

rating (W)

 
 

size

method

 
 
   
  
  
  
  
  
  
  
 
  

Water

208

21

4410

9

10

Plug-in

1

  

heater

 
  
  
  
  
  
  
 
   
  
  
  
  
  
  
  
 
  

HVAC

208

10

3600

10

12

Hardwire

3

   
 
  
  
  
  
  
  
 
   
  
  
  
  
  
  
  
 

POWER
PANEL SCHEDULE

 
 
 

Circuit #

Circuit breaker

Conductor

General

Bus loads (in watts)

 
  
 
  

rating (A)

size (AWG)

use