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Residential Feeder Load Calculation Quick Start

Posted on July 22nd, 2014. Last updated on June 14th, 2023.

This article shows you how to set residential feeder load calculations in Design Master Electrical. This will help you avoid the most common errors customers encounter when first using the calculation.

Set the Load Calculation Method Correctly

1. Run the Panels command.1a. Create a panel if you have not already.
2. Press the Feeder and Service Calculation Settings button.
3. Make sure Load Calculation Method is set to Default.
4. Beside Load Calculation Method, press the Set Default button.
5. Choose the Load Calculation Method that you want to use for your project. This will be the default Load Calculation Method setting for all of the panels and other distribution equipment in your project.For more information about the options available, see this article on feeder and service calculations.
6. Press the OK button to return to the Feeder and Service Calculation Settings dialog box.6a. If you selected a Multifamily Dwelling, Marina, Mobile Home Park, or RV Park option, and you are configuring the most downstream panel, enter a value in the Multifamily Dwelling Units, Shore Power Receptacles, Mobile Homes, or Recreational Vehicle Sites field. The value you enter will carry over to upstream panels. For example, panel H1 feeds three panels—A, B, and C—that each serve a single dwelling unit. On panels A, B, and C, the value should be set to 1. On panel H1, the value should be set to 0.

Set the Default General Lighting Circuit Value Correctly

1. In the Feeder and Service Calculation Settings dialog box, make sure the Default General Lighting Circuit Value is set to Default.
2. Beside Default General Lighting Circuit Value, press the Set Default button.
3. Select No, then press the OK button to return to the Feeder and Service Calculation Settings dialog box.

Set Occupancy Areas Correctly

1. In the Occupancy Areas section of the Feeder and Service Calculation Settings dialog box, set Area 1 to Dwelling Unit, 3 VA / sf.
2. For Area 1, enter the area of the dwelling unit in the Area field, then set Demand Factor to Dwelling Unit.
3. Press the OK button to return to the Panels dialog box.

Set General Lighting Circuit Setting on Circuits Correctly

1. Press the Go to Circuiting button to open the Circuiting dialog box.
2. Connect devices or use the Set Fixed Loads button to set the loads on the circuits.2a. For circuits that have lighting connected to them, change the General Lighting Circuit value from Default to Yes. The load on these circuits will be ignored in the total panel load. It is assumed they are part of the general lighting load defined by the occupancy area specified for the panel.

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