Standard Residential Service Calculations

Ampacity Correction
Temperature Correction
Continuous Load Correction
Conduit Fill Correction
Minimum Number of Circuits
Bus Bar Ampacity
Conductor Resistance
Resistance Change
Motor Disconnect Sizing
Full Load Current Interpolation
Motor Conductor Sizing
Motor Overcurrent Protection
Motor Overload Sizing
Lighting Loads
Fixed Appliance Loads
Range Loads
Range Loads Note 1
Range Loads Note 2
Dryer Water Heater Loads
Heat AC
Standard Residential Service
Optional Residential Service
Standard Multi Family Service
Optional Multi Family Service
Commercial Services
Optional School Services
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The calculation for a single family dwelling is the most difficult service calculation to make. There are numerous special rules which all need to be considered when answering the question of what is the smallest allowable service size.

NEC 220 lists all the details. Here is a run-down of the various article numbers which need to be considered:

Find service aspect practice problems here by topic:

Residential Lighting Loads 153    Audio Support
Net Lighting and Appliance Demand 154   Audio Support
Non-coincident Loads 157    Audio Support
Complete Service Calculations 167    Audio Support
Residential Electric Service Calculations Worksheet
Residential Service Calculations 171
Residential Service Calculations 172
Residential Service Calculations 173
Residential Service Calculations 174
Residential Service Calculations 175



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