Subject: Online Coil Inductance Calculators yeild different Results
Designing an open air coil wound on PVC pipe with the following specs ...
Wire = 12 gauged insulated electrical wire from Lowes
- Wire Diameter = .125 including the insulation
- Turns per inch = 8
- Total Turns = 212
- Coil Diameter = 2 inches (5.08 cm)
- Coil Radius = 1 inch (2.54 cm)
- Coil Length = 26.5 inches (67.31 cm)
- Relative Permeability = 1
I get different results depending on which online calculator I use... (see 4 examples at the end of this post)
Calculator 1, 2, 3, & 5 shown below are at least between 5% & 10% the same ...
But Calculator # 4 is way different
I've also run the numbers myself using the equations offered on each site and get the same results as the sites calculator ...
Question 1: Which Calculator is most accurate
Question 2: Which Equation for an open air inductor is most accurate?
(Understanding that in practice results may differ)
Calculator links, inputs, and outputs listed below.
Thanks for any help.
-------------------------------
Calculator # 1:
All About Circuits Coil Inductance Calculator
At: https://www.allaboutcircuits.com/tools/coil-inductance-calculator/
Input:
Coil Radius = 2.54 cm
Solenoid Length = 67.31 cm
Nummber of turns = 212
Relative Permeability = 1
Output:
170.07 uH
-------------------------------
Calculator # 2:
Telsa Scientific Coil Inductance Calculator
At: https://www.teslascientific.com/products/coil-inductance-calculator/
Input:
Coil Diameter = 2 inches
Coil Length = 26.5
Number of turns 212
Output:
164.029 uH
-------------------------------
Calculator # 3:
TranslatorCafe.com Single-Layer Coil Inductance Calculator
At: https://www.translatorscafe.com/uni...tor/coil-inductance/?D=2&Du=cm&l=1&lu=cm&N=10
Input:
Coil Diameter = 2 inches
Number of turns = 212
Length of Coil = 26.5 inches
Output:
179.7369 uH
-------------------------------
Calculator # 4:
EEWeb Coil Inductance Calculator
At: https://www.eeweb.com/tools/coil-inductance/
On the right of the Inputs ... Select "Coil Inductance Calculator"
Inputs:
Number of Turns = 212
Loop Diameter = 2 inches
Wire Diameter = .125 inch (diameter of insulation surrounding 12 guage wire)
Relative Permeability = 1
Output:
0.00409 H or 4.09 mH
-------------------------------
Calculator # 5:
Rimstar.org Inductance Calculator
At: https://rimstar.org/science_electronics_projects/coil_design_inductance.htm
Input:
Relative Permeability = 1
Number of Turns = 212
Radius= 1 inch
Length = 26.5 inches
Output:
170.5218 uH
Designing an open air coil wound on PVC pipe with the following specs ...
Wire = 12 gauged insulated electrical wire from Lowes
- Wire Diameter = .125 including the insulation
- Turns per inch = 8
- Total Turns = 212
- Coil Diameter = 2 inches (5.08 cm)
- Coil Radius = 1 inch (2.54 cm)
- Coil Length = 26.5 inches (67.31 cm)
- Relative Permeability = 1
I get different results depending on which online calculator I use... (see 4 examples at the end of this post)
Calculator 1, 2, 3, & 5 shown below are at least between 5% & 10% the same ...
But Calculator # 4 is way different
I've also run the numbers myself using the equations offered on each site and get the same results as the sites calculator ...
Question 1: Which Calculator is most accurate
Question 2: Which Equation for an open air inductor is most accurate?
(Understanding that in practice results may differ)
Calculator links, inputs, and outputs listed below.
Thanks for any help.
-------------------------------
Calculator # 1:
All About Circuits Coil Inductance Calculator
At: https://www.allaboutcircuits.com/tools/coil-inductance-calculator/
Input:
Coil Radius = 2.54 cm
Solenoid Length = 67.31 cm
Nummber of turns = 212
Relative Permeability = 1
Output:
170.07 uH
-------------------------------
Calculator # 2:
Telsa Scientific Coil Inductance Calculator
At: https://www.teslascientific.com/products/coil-inductance-calculator/
Input:
Coil Diameter = 2 inches
Coil Length = 26.5
Number of turns 212
Output:
164.029 uH
-------------------------------
Calculator # 3:
TranslatorCafe.com Single-Layer Coil Inductance Calculator
At: https://www.translatorscafe.com/uni...tor/coil-inductance/?D=2&Du=cm&l=1&lu=cm&N=10
Input:
Coil Diameter = 2 inches
Number of turns = 212
Length of Coil = 26.5 inches
Output:
179.7369 uH
-------------------------------
Calculator # 4:
EEWeb Coil Inductance Calculator
At: https://www.eeweb.com/tools/coil-inductance/
On the right of the Inputs ... Select "Coil Inductance Calculator"
Inputs:
Number of Turns = 212
Loop Diameter = 2 inches
Wire Diameter = .125 inch (diameter of insulation surrounding 12 guage wire)
Relative Permeability = 1
Output:
0.00409 H or 4.09 mH
-------------------------------
Calculator # 5:
Rimstar.org Inductance Calculator
At: https://rimstar.org/science_electronics_projects/coil_design_inductance.htm
Input:
Relative Permeability = 1
Number of Turns = 212
Radius= 1 inch
Length = 26.5 inches
Output:
170.5218 uH