Template · Engineering
Single-phase voltage drop calculator
Estimate two-wire loop resistance, voltage drop, percentage drop, and load voltage from current, one-way distance, and conductor resistance.
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XLSXCSVODSXMLNumbers| Single-phase voltage drop calculator | |||||||||
| Example data — replace the blue input cells with your own. | |||||||||
| Estimate two-wire loop resistance, voltage drop, percentage drop, and load voltage from current, one-way distance, and conductor resistance. | |||||||||
| Populated records | 6 | Prepared capacity used | 10.0% | ||||||
| Maximum voltage drop (V) | 19.4400 | Peak: Load volts | 340.5600 | ||||||
| Average: Load volts | 217.3491 | ||||||||
| Active rows bar | ██ | ||||||||
| 60 record rows (6 sample rows shown). Blue cells are inputs; dark cells calculate. | |||||||||
| Circuit | Supply volts | Load amps | One-way length m | Conductor ohm per km | Loop resistance ohm | Voltage drop V | Drop share | Load volts | Scale bar |
| Subpanel feeder A | 240.0000 | 16.0000 | 40.0000 | 4.5000 | 0.3600 | 5.7600 | 2.4% | 234.2400 | ████████ |
| Lighting branch B | 120.0000 | 10.0000 | 25.0000 | 7.2000 | 0.3600 | 3.6000 | 3.0% | 116.4000 | ████ |
| Outdoor pump run C | 240.0000 | 20.0000 | 60.0000 | 3.0000 | 0.3600 | 7.2000 | 3.0% | 232.8000 | ████████ |
| Subpanel feeder A (4) | 360.0000 | 24.0000 | 60.0000 | 6.7500 | 0.8100 | 19.4400 | 5.4% | 340.5600 | ████████████ |
| Lighting branch B (5) | 96.0000 | 8.0000 | 20.0000 | 5.7600 | 0.2304 | 1.8432 | 1.9% | 94.1568 | ███ |
| Outdoor pump run C (6) | 300.0000 | 25.0000 | 75.0000 | 3.7500 | 0.5625 | 14.0625 | 4.7% | 285.9375 | ██████████ |
Showing the first 16 of 72 rows and 10 of 10 columns. Cells with formulas show the formula on hover.
| Single-phase voltage drop calculator |
| Method, inputs, and limits for this workbook. |
| What it does |
| Estimate two-wire loop resistance, voltage drop, percentage drop, and load voltage from current, one-way distance, and conductor resistance. |
| How to use it |
| Replace the fictional records in blue cells with your own data. Keep the dark formula cells. Use the units stated in the column headers and keep each record on one row. Read the calculated columns and inspect the results before using them.… |
| Formulas and method |
| Loop resistance equals twice the one-way length in kilometers times conductor resistance in ohms per kilometer. Voltage drop multiplies load current by loop resistance, and load voltage subtracts voltage drop from supply voltage. |
| Assumptions and limits |
| Models resistive single-phase DC or unity-power-factor AC circuits. Three-phase factors, cable reactance, ambient temperature derating, and electrical code limits must be checked separately. |
| Missing numeric inputs |
Showing the first 16 of 72 rows and 4 of 4 columns. Cells with formulas show the formula on hover.
What does this template do?
Estimate two-wire loop resistance, voltage drop, percentage drop, and load voltage from current, one-way distance, and conductor resistance.
Loop resistance equals twice the one-way length in kilometers times conductor resistance in ohms per kilometer. Voltage drop multiplies load current by loop resistance, and load voltage subtracts voltage drop from supply voltage.
Models resistive single-phase DC or unity-power-factor AC circuits. Three-phase factors, cable reactance, ambient temperature derating, and electrical code limits must be checked separately.
The working tab keeps editable inputs separate from formulas, with 6 populated sample rows, summary KPIs, an in-cell scale bar, and room for 60 records. The Notes tab explains the method and how to extend the range. All example records are fictional and can be replaced. Download a workbook format to retain formulas, or CSV when you need calculated values only.
What’s inside
- Loop resistance equals twice the one-way length in kilometers times conductor resistance in ohms per kilometer. Voltage drop multiplies load current by loop resistance, and load voltage subtracts voltage drop from supply voltage.
- 60 prepared record rows with blank-row guards and in-cell scale bars
- Summary KPI block with peak, average, and capacity tracking
- Blue input cells, typed dates and numbers, and frozen column headers
- Notes with the method, assumptions, and range-extension instructions
Which tabs does the workbook have?
| Tab | What it holds |
|---|---|
| Worksheet | Estimate two-wire loop resistance, voltage drop, percentage drop, and load voltage from current, one-way distance, and conductor resistance. |
| Notes | How to use the workbook, formula method, assumptions, and file format limits. |
What formulas does this template use?
This template holds 306 formulas in 374 cells across 2 tabs, so 82% of its cells calculate. They use 12 distinct functions; the longest formula is 134 characters.
| Function | Uses | What it does |
|---|---|---|
IF | 664 | one result when a test is true, another when false |
COUNT | 242 | counts numeric cells |
MAX | 183 | largest value |
OR | 120 | true when any test is true |
MIN | 61 | smallest value |
REPT | 61 | repeats text |
ROUND | 61 | rounds to a number of digits |
ISNUMBER | 60 | true for a number |
NOT | 60 | reverses true and false |
COUNTA | 4 | counts non-empty cells |
COUNTIF | 2 | counts cells meeting one condition |
AVERAGE | 1 | mean of numbers |
Counted from the workbook itself. Only functions that Excel, LibreOffice Calc, Google Sheets and Apple Numbers evaluate the same way are used, so the formulas survive every download format.
How do you use it?
- Replace the fictional records in blue cells with your own data. Keep the dark formula cells.
- Use the units stated in the column headers and keep each record on one row.
- Read the calculated columns and inspect the results before using them. Clear unused input rows; keep their formulas.
- The prepared range holds 60 records in rows 11–70. Extend formulas and summary ranges together if you add more rows.
What is it good for?
- Estimate two-wire loop resistance, voltage drop, percentage drop, and load voltage from current, one-way distance, and conductor resistance
- Replacing the labeled fictional records with your own figures
- Checking a calculation before adapting it to a larger workbook
Questions about this sheet
How is the result calculated?
Loop resistance equals twice the one-way length in kilometers times conductor resistance in ohms per kilometer. Voltage drop multiplies load current by loop resistance, and load voltage subtracts voltage drop from supply voltage.
What assumptions should I check?
Models resistive single-phase DC or unity-power-factor AC circuits. Three-phase factors, cable reactance, ambient temperature derating, and electrical code limits must be checked separately.
Can I add more than 60 records?
Yes. Copy the formula columns into new rows and extend every summary range to include them. Keep inputs and formulas in their original columns.
Are the example records real?
No. All example data is fictional and intended to demonstrate the formulas. Replace it before using the workbook for your own work.