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Most home inspectors and many experienced electricians guess at the electrical service size requirements using rules of thumb (usually involving only square footage).  With the rapid growth in the number of electrical appliances and electronic equipment during the past few years, making a guess could be a costly mistake. 

The Residential Electrical Service Size Calculator takes the guesswork completely out of determining the electrical service size requirement.  The Calculator requires no special knowledge of electrical systems or codes.  All you do is make basic observations about the house and fill in the blanks.  The Calculator lets you enter electrical loads in either Amps or Watts.  the required information can almost always be found on the nameplates of appliances and mechanical equipment.

The Calculator will tell the "Demand Load" (a trade term, different from "connected" load), the nearest standard size panel and main breaker, the conductor (wire) size and the conduit size.    

The Calculator's worksheet can be filled out in about three to four minutes and can be included with any inspection in PDF format.      

Features of the Calculator:
-Automatically calculates the total demand load for a residential single family dwelling
- provides the demand load in both volt-amperes and Amperes
- Automatically adds the minimum of small appliance and laundry branch circuits
- Automatically determines the heating and air conditioning demand load
- Determines the standard service panel size for the system
- Determines the service wire gauges in both aluminum and copper
- Calculations are based on the National Electrical Code (optional method)
- NEC section references under each heading

NOTE: This worksheet is intended to be used as a general guide.  It does not account for all possible factors involved in determining the size of an electrical service. Consult a qualified electrician or the NEC® for additional information.

Digital download

Download the Calculator Free

or
Purchase
The entire collection of electrical calculators on CD

$9.⁹⁹

Residential Single Family Service Calculator

Electrical Conduit Fill/Size Calculator
Enter any combination of up to 30 different conductor sizes or types in any quantity to determine the conduit size for every type of conduit recognized by the NEC^®.

Power Factor Correction - 3 Calculators in one
Allows you to choose either Voltage and Amperage input or Wattage input. 

The calculator can also be used to determine transformer size 

3 Phase 4 Wire Wye - 8 Calculators in one
Neutral current
Phase leg power in V-A
Phase leg power in Watts
System power in V-A
System power in Watts
Line to neutral voltage
Transformer phase current
Transformer phase power  

Fault Current Calculator
Utility to service equipment
Service equipment to panel
Panel to sub-panel
Sub-panel to load
Transformer vault

The calculator is essentially an Ohm's Law calculator.  The difference between the BestInspectors.Net  Voltage, Current and Power calculator and most Ohm's Law calculators is that Ohm's Law calculators are usually geared toward electronics, not power systems.  This calculator is for power distribution systems.  The calculator has a Power Factor component to it.  Most Ohm's Law calculators do not.  Calculations can be performed quickly and easily using name plate data or actual measurements.

The calculator is also a training calculator.  There is a list of relevant electrical terms and units of measure on the screen at all times.  Every time you enter a value, the related terms are highlighted.  Once you have entered the values needed to complete the calculations, the remaining input fields are blacked out so you don't inadvertently enter a conflicting value.  For example, if you have entered Voltage and Wattage values, the Current input field is blacked out so you can't insert an invalid value.  The Current in this case would be among the calculated values in the results section.

Digital download

Download the Calculator Free

Inspection Report Comparison Chart

Note: all BestInspectors.Net ™ inspection report systems include the complete BestInspectors.Net ™ set of Business Tools and customizable Pre-inspection Agreement

MS International, LLC
Best Inspectors Network
P.O. Box 326
Sylvania, Ohio 43560-0326

Software is not refundable or returnable.  Defective media may be exchanged for the same title within 30 days of purchase. After 30 days, replacement CD's are available for a nominal fee.

Mail your payment to:

Management Science Institute
Best Inspectors Network
P.O. Box 326
Sylvania, Ohio 43560-0326

For fastest service, pay by credit card.  It's fast, safe, and secure.

Make your PayPal payment to:
"msipp AT bestinspectors.net"
Replace "AT" in the e-mail address above with the "@" sign

Software is not refundable or returnable.
Defective media may be exchanged for the same title within 7 days of purchase.

Be sure to visit the Home Inspection  Store (hosted eBay) for additional items
The Home Inspection  Store features software, self-study courses, and training CD's

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Please consult our Frequently Asked Questions (FAQ) pages before calling for technical support