This article will show how to convert electrical resistance measurement units from milliohms (mΩ) to Ohms (Ω). We will cover essential definitions, provide examples, share relevant formulas, and present tables, along with answers to common questions.
Definitions of Ohm and Milliohm
Let’s get started by understanding the key definitions of Ohm (Ω) and Milliohm (mΩ). Understanding these terms will enable you to perform conversions with confidence.
What is Ohm?
The ohm (Ω) is the SI derived unit of electrical resistance. It is defined as the resistance between two points of a conductor when a constant potential difference of one volt is applied across those points, producing a current of one ampere in the conductor, assuming no additional electromotive force is present.[1]
According to SI prefixes[2], which are based on powers of 10, an ohm (1 Ω) is equivalent to one thousand milliohms (103 mΩ or 1,000 mΩ).
What is Milliohm?
A milliohm (mΩ) is a unit of electrical resistance in the SI system equal to one thousandth (1/1,000) of an ohm (10-3 Ω).
It is commonly used in fields such as power distribution, precision electronic testing, and industrial motor evaluation. Accurately measuring very low resistance values is essential for determining the efficiency and reliability of these systems.
mΩ to Ω formula
Let’s take a closer look at the conversion formula so you can carry out these conversions independently, whether using a calculator or doing it manually with pencil and paper.
The milli- prefix in the International System of Units (SI) corresponds to a multiplier of 10-3 (0.001).
To convert milliohms (mΩ) to ohms (Ω), divide the resistance value in milliohms by 103 (1,000,000), since 1 ohm equals 1,000 milliohms.
R(Ω) = R(mΩ) ÷ 103 = R(mΩ) ÷ 1,000
Or remember the mΩ-to-Ω conversion factor: 1 mΩ = 10-3 = 0.001 Ω
mΩ to Ω conversion table
The conversion table below provides a handy reference for converting electrical resistance measurement units from milliohms (mΩ) to ohms (Ω). It covers a range from 0.1 mΩ to 1,000 mΩ, allowing for easy and quick conversions between these units of measurement.
| Milliohms (mΩ) | Ohms (Ω) |
|---|---|
| 0.1 mΩ | 0.0001 Ω |
| 0.5 mΩ | 0.0005 Ω |
| 1 mΩ | 0.001 Ω |
| 2 mΩ | 0.002 Ω |
| 4 mΩ | 0.004 Ω |
| 5 mΩ | 0.005 Ω |
| 10 mΩ | 0.01 Ω |
| 20 mΩ | 0.02 Ω |
| 30 mΩ | 0.03 Ω |
| 40 mΩ | 0.04 Ω |
| 50 mΩ | 0.05 Ω |
| 60 mΩ | 0.06 Ω |
| 70 mΩ | 0.07 Ω |
| 80 mΩ | 0.08 Ω |
| 90 mΩ | 0.09 Ω |
| 100 mΩ | 0.1 Ω |
| 200 mΩ | 0.2 Ω |
| 500 mΩ | 0.5 Ω |
| 800 mΩ | 0.8 Ω |
| 1,000 mΩ | 1 Ω |
Examples
Now, let's look at an example that illustrates the calculations required to convert from milliohms to ohms (mΩ to Ω).
Example: PCB Trace Resistance Evaluation
High-speed printed circuit boards (PCBs) demand very low resistance on their traces to minimize signal loss. Converting trace resistance values from milliohms to ohms provides clarity in circuit simulation and analysis.
If a PCB trace has a resistance of 5 mΩ, what is the equivalent measurement in ohms?
Solution
Since 1 ohm (Ω) = 1,000 milliohms (mΩ), we can convert 5 mΩ to milliohms by using the following formula:
Therefore, the 5 mΩ electrical resistance is equivalent to 0.005 Ω.
To solve the problem with our calculator, follow the steps below:
- Enter the value in milliohms: For this example, enter
5into the From box. - View the result: The converter instantly calculates and displays the equivalent value in ohms:
0.005 Ω.
FAQs
Is 1 milliohm or 1 ohm larger?
An ohm (Ω) is a thousand times bigger than a milliohm (mΩ). Here are the relationships between the units:
1 Ω = 103 = 1,000 mΩ1 mΩ = 10-3 = 1 ÷ 1,000 = 0.001 Ω
How to convert from milliohms to ohms?
To convert electrical resistance from milliohms (mΩ) to ohms (Ω), follow these simple steps:
- Step 1: Write down the electrical resistance value in milliohms (mΩ).
- Step 2: Divide it by a thousand (
1,000). - Step 3: The result is the value of the electrical resistance in ohms (Ω).
Why do I need to convert milliohms to ohms?
Converting milliohms to ohms is especially useful when you need to express resistance in the standard SI unit, which is ohms (Ω). By converting to ohms, you ensure that your measurements are expressed uniformly, which simplifies comparisons and integration with formulas like Ohm’s Law.
For instance, if you measure a resistance of 2.5 mΩ, converting it to ohms (2.5 mΩ × 0.001) gives you 0.0025 Ω. This conversion aligns your data with common engineering practices and reduces errors in documentation and computation.
You now know how to convert electrical resistance from milliohms (mΩ) to ohms (Ω). You can quickly use our calculator to convert between the electric resistance measurement units to save time for future calculations.
