1. Parameters . The variables used in this tool are the diameter of the wire conductor and the diameter of the wire loop. Description The inductance calculated using this tool is the inductance of the loop bounded by the flat conductor and the ground planes above and below the conductor. The inductance of a straight wire and coil with a given inductance in micro Henry the. Corrected Inductance is the Current Sheet Inductance value with corrections for round wire and frequency included. Ground plane is assumed to be perfectly conducting and of infinite extent. The round-wire geometries are loops of wire with various shapes. 2. The geometrical mean distances for a round conductor with radius r, for a flat wire of width a, and for a square wire with side b are: R e . L L = length of the wire. As a result of this effort, this inductance calculator will return only a single value of inductance. Inductance of a Square Loop of Wire. Dimensions are in meters. The variables used in this tool are the diameter of the wire conductor and the diameter of the wire loop. The equation of the circular spiral coil, motivated by the Archimedean spiral coil can be described by. N is the number of turns in the coil. The outer diameter of the wire (with insulation) should be using in this calculator. Moving between the boxes by clicking or using the 'TAB' button on your keyboard, will update the result. 65 mm without insulation and 0. Serway, John W. u r = relative permeability of the core material (air = 1) turns = number of turns on the coil. As opposed to deliberate inductance, which is introduced into the circuit by the use of an inductor, parasitic inductance is almost always an undesired effect. Berkner, K. 99 – £ 44. Wind the wire as cleanly and closely as possible, and apply CA glue during the process to secure. 4 mm. The wire length is calculated as an average of the evenly spaced turns, this results in a estimated spiral length from being calculated as single circles. Multi-Layer Coil Inductance Calculator. Assumptions and Limitations Dimensions are in meters. Wire is assumed to have circular cross section. 4) + (wire spacing / 25. These two signals make a complete loop. Parallel conductors ( current in opposite directions)There are several little different from each other empirical formulae for calculating the inductance as a rectangular loop of wire. Grover} IvductanceofPolygonalCoils. 00032 Henry) when the frequency is 3333 kc (3333000 cycles/sec)R ≈ l σ(δs2πa) (δs ≪ a) The impedance of a wire of length l and radius a ≫ δs is given by Equation 4. The length of wire used is also calculated. In the model, the wire width of the coil is modelled as constant current-carrying filaments. Inductance is a property of electrical circuits that causes a voltage to be induced in a conductor when the current in the conductor changes. This formula applies at 'low' frequencies (<30MHz) ) using enameled copper wire. Dimensions are in meters. The first thing to know when calculating the impedance of a wire is whether it's a coaxial or twisted pair cable. Impedance of the coil inductance is defined under the formula: XL = 2πƒL. The effective diameter Deff obtained from here is used to calculate the inductance of the single-layer helical coil: where: μ: permeability of the coil core. Its a little thought experiment. Meter can measure 0. R = R i + a θ, θ i ≤ θ ≤ θ o. Internal self inductance; External self inductance; Mutual inductance; Any capacitive reactances; For now we can ignore wavelength as it pertains to cable length as my specific question pertains to frequencies less than 100kHz and wire lengths less than 100m so these effects can be ignored. This correction, in microhenrys, is added to the inductance. Plug these values into the formula: L = (N^2 * μ * A) / l. r = average winding radius in inches. The inductor impedance calculator calculates the impedance of an inductor based on the value of the inductance, L, of the inductor and the frequency, f, of the signal passing through the inductor, according to the formula, XL= 2πfL. To actually make the coil, [Drew] recommends some means of magnification, and a supply of CA glue. On the left side, the LCR meter measures one cable. To find out how much inductance a coil has, do the following: Step 1: Enter the coil radius Rc or the coil diameter Dc (in Advanced mode). Now lets put this equation to use. Coaxial Cable Inductance. You can choose from single-layer solenoid, multi-layer solenoid and flat spiral coil forms. To calculate the inductance of a single-layer, air-core coil: 1. Discrete Structures: z Wire Inductance Calculator z Strap Inductance Calculator z Air Core Solenoid. I also have a formula for the AC resistance of a solid wire derived in the book Electromagnetic compatibility Handbook by Kaiser and is very simply derived as follows:. The first thing to know when calculating the impedance of a wire is whether it's a coaxial or twisted pair cable. If the windings are fixed in place, then this force is unable to do work (i. H H = height of the wire above the plane. w = width of winding (in inches) N = number of turns. Inductors, also know as choke, coil, or reactor is a passive electrical component that stores energy in its magnetic field. Enter then number of turns in the coil, one half of the coil radius (also called average radius) and the width of the coil. 37mm2, and a Rubadue S11NC133ECC-7 has an area of 4. Example 11. 2 µH to 10 µH. 5 times larger cross section to be selected. W. 1 Inductance of a circular antenna, where: Lant 31. e. The equation of the circular spiral coil, motivated by the Archimedean spiral coil can be described by. You can select measurement units - mm or inches, and also AWG or SWG wire number - the wire diameter will be determined automatically. PI Network Impedance Matching. radius. Example 1: Find the inductive reactance of a coil that has an inductance of 320 µH (0. Select your coil geometry, enter the dimensions, and select the units. The inductance calculated in this tool is the self-inductance, which is used in some simulations and is only part of a total loop inductance. Six Inductor Parameters 4. k. The capacitance calculated using this tool is the capacitance between a flat conductor and the ground plane over the conductor length. Using the LC Constant Calculator. Flat Wire Inductance Calculator. eff. Or even simpler: l = c, D = 2c. The calculator allows calculating the number of windings of the multilayer air core coil on a rectangular former at the design stage. Measuring Capacitance Range: 0. 01 pF - 100mF. The inputs to this calculator are length distance between the two conductors and diameter of the wire. The equation above is from “Inductance Calculations” by F. If the radius (for circular coils) or half the average side length (for rectangular coils) exceeds twice the coil length (F21), the coil is. Robert N9NQCables with copper-clad aluminium wire (CCAW) should have two AWG sizes larger (e. Low frequency, perfect conductor: no skin effect. Find Wire Self Inductance Calculator at CalcTown. The capacitance calculated using this tool is the capacitance between two coplanar flat conductors. R= radius of coil in inches. The user enters target inductance and maximum operating current : the first thing. Wire Loop Inductance Description. Calculate the parallel wire impedance, inductance, capacitance, and propagation delay using this online electrical calculator. This method is derived by solving Neumann’s integral formula in a cylindrical coordinate system, and a numerical tool is used to determine the value of mutual inductance. The inductance calculated using this tool is the external inductance of the loop bounded by the flat conductor and the ground plane. Find magnetic permeability and inductance factor of an unknown ferrite toroid core. The round-wire geometries are loops of wire with various shapes. Use our free online coil inductance. Finally, we have two equations for the inductance of microstrip and stripline traces. The HCV utilize flat-wire construction with low DCR and high efficiency performance. The mutual inductance M21 of coil 2 with respect to coil 1 is the ratio of the flux through the N2 turns of coil 2 produced by the magnetic field of the current in coil 1, divided by that current, that is, M21 = N2Φ21 I1. Coplanar Waveguide With Ground Calculator. It is independent of the potential difference between the conductors and the total charge on them. Frequency: You must enter a frequency for the calculator to work Calculating inductance: To calculate the inductance, input the capacitance into the appropriate cell Calculating capacitance: To calculate the capacitance, input the inductance into the. For very high frequencies the inner inductance gets zero and the overall inductance tends to its outer inductance. Formula. . Having this in consideration, together with the particularities of planar coils previously mentioned, the complexity associated with the auto-inductance calculation for flat. wire inductance L int = µ 0/8π, and the resulting inductance is higher than the inductance at high frequency when the skin effect becomes dominant. Spiral Coil Inductance Calculator. Most of online calculators enable to find inductance of the coil knowing its winding dimensions and number of turns. Similarly, the leakage inductance can be a part of a reso-nant impedance that enables soft switching [3], [4]. F. Many magnetic field coupling circuits, such as chokes and transformers, take advantage of a coil’s magnetic storage properties. Below you see a transmission line consisting of 2 parallel wires. Wires are assumed to reside in a homogeneous medium. 5Turns 25-100MHZ. Very suitable for small value capacitor and inductor measurement. r = average winding radius in inches. Coil Inductance Calculator. For a notionally thin wire, you can say that the magnetic flux produced by any part of the flow of current couples to flux produced by all other parts of the flow of current. Use this calculator to find the inductance of a multi-layer coil. The calculation is based on the classic Wheeler's formula for single-layer inductance (air core, tightly wound), which dates back to the radio days of the 1920s: L = 0. Calculate the A. 67r and the frequency is less than 10 MHz. A twisted-pair cable is simply two wires that are twisted together so as to reduce radiated EMI (electromagnetic interference) and mitigate the effects of received EMI. LC Meter LC200A. H = Factor corresponding to coil length/diameter ratio. Coil Geometry: Select the geometry of your coil from the list. Please feel free to use them. Can we obtain the same low inductance by twisting two wires at audio frequencies?. The value of M neatly encapsulates the physical properties of circuit elements and allows us to separate the physical layout of the circuit from the dynamic quantities, such as the emf and the current. In all cases, the current is assumed to flow in the outer surface of the conductors. Rectangle Loop Inductance Calculator. A is the cross-sectional area of the toroid core. For single turn coils, formula #58 from F. 50 cm in diameter and 4. Note that the measurement unit may be chosen for the loop diameter and wire diameter. Formula in Inch Units: L = r2N2 / (9r + 10A); N. Figure 14. Table 6 shows the cross-section area for a round wire versus. S. Lay (=pitch) direction. For my results, I find that the minimum inductance is 292 nH per meter when ( w/h) = 1. Voltage (V)A circuit element used to provide self-inductance is known as an inductor. 000uH to 100. H= height of coil in inches. PCB Trace Width Calculator This tool uses formulas from IPC-2221 to calculate the width of a copper printed circuit board conductor or "trace" required to carry a given current while keeping the resulting increase in trace temperature below a specified limit. Optimization results for example 2. where N is the number of turns, r is the inside radius in cms, and L is the inductance in uH. An alternative formula is:This calculator is designed to measure the wire coil inductance, given the number of turns, the diameter of the loop, the diameter of the wire, and the permeability of the medium. 081 uH. b. Calculate the inductance using a mathematical formula. ) coils, by setting the number of turns per layer, NT to 1 and setting the. length. The program has additional plugins to. The inductance of the loop. The Smith Chart graphically maps S11=reflection coefficient= (ZL-Z0)/ (ZL+Z0) to Load Impedance (ZL), normalized to Z0 (source impedance = center of chart). Inductance is the tendency of an electrical conductor to oppose a change in the electric current flowing through it. For this calculation the diameter and length units are in cm. Loop length and width must be greater than the wire diameter. I selected a 56-pF NPO capacitor for the tuned circuit because it is in the right range, and a dozen or so were in my junk box. 2. Equation 4 allows us to calculate the inductance of a wire loop [1]. The formula to Calculate the inductance of parallel wire ( Power and Ground System) L = 10. With this approx-imation, the effective diameter D. Choose units for a and W. No closed-form exists to calculate the inductance of a generic polygon of wire. where d is the mean diameter of the winding, in centimeters, and N is the total number of turns. 25664 * 10-6 T*m/A. Internal inductance is not included in this model, but may be calculated using the Wire Internal Inductance tool. Where: Lwop L w o p = inductance of the wire over plane in henries (H) μ0 μ 0 = permeability of free space = 4π×10−7. 68 × 10^(-8) Ω × m . The larger the mutual inductance M, the more effective the coupling. The inductance of a rectangle loop has three geometric variables: W – rectangle long side; h – rectangle short side; d – wire diameter; Rectangle Loop Inductance Model. Straight conductor. . (2) θ = 2 π N. Lwire=2l⎧⎨⎩ln⎡⎣(2LD)⎛⎝1+√1+(D2L)2⎞⎠⎤⎦−√1+(D2L)2+μ4+(D2L)⎫⎬⎭Lwire=2l{ln[(…[μH] where L flat: inductance of the conductor [μH] ℓ : length of the conductor [mm] w: width of the conductor [mm] t: thickness of the conductor [mm]This tool is designed to calculate the inductance of a square loop of wire given its dimensions (width, height and diameter of the wire used). D D = diameter of the wire. Coax Inductance Description. "Coil64" is a free coil inductor calculator, that allows calculating: single-layer and multilayer air core inductors, toroidal air core coil inductance, inductors on ferrite rings, in pot core, flat coils on the PCB, and also LC tank parameters. 005 in × 92 (36-n)/39. This Coil Calculator is a professional and easy-to-use electrical tool for electrical engineers and designers. For example, if the coil bobbin width is 30mm, a distance of 15mm is at the coil edge. Air Core Flat Spiral Inductance. If you have any suggestions for improvement please email [email protected]. 1 inch = 0,0254m=2,54cm = 25,4mm. Rule of Thumb # 7: In the special case of two flat, wide conductors, adjacent to each other, with a spacing comparable to their line width, the total inductance of either one is just 10 nH/inch. Loop diameter is assumed to be much larger than wire diameter. Obviously, a very natural description for every electrical engineer is the usage of lumped element networks constructed from resistance, inductance and capacitance (RLC). R = R i + a θ, θ i ≤ θ ≤ θ o. Inductance is one of the transmission line parameters. Coplanar Capacitance. In all cases, the current is assumed to flow in the outer surface of the. Graph Paper. To use this tool, just fill in the required fields and click on the "calculate" button. A rectangle loop inductance calculator is a tool used to calculate the inductance of a rectangular loop of wire. Value of inductance is normally directly proportional to diameter of the coil and a square of number of turns. Table of Contents. All of the above logic of reasoning and derivation of formulas, starting from the Neumann formula. Reset the calculator after each calculation for best results. Multiply the number of turns and diameter of the coil. Enter the width of the conductor:imity factor Φ. I've been working on a project recently which requires me to build an inductor, however in my research I found many different equations (with a range of variables used and giving very different results to the same coil specifications) and I was wondering what equation I should use. Consider a MCU SPI dataline, 1mm from the sensitive signal trace, and parallel for 40mm. where M is defined to be the mutual inductance between the two devices. Flat Wire Inductor For a flat wire, ribbon or PCB track, showing the formula used. Keep in mind that this formula applies mainly to solenoid-shaped inductors with a uniform cross-sectional area and. This calculator computes the inductance of a microstrip etched on a PCB. Calculate the inductance (L) in henries (H). Lcoil = μrμ0N 2A l = μrμ0N 2πr2 l L c o i l = μ r μ 0 N 2 A l = μ r μ 0 N 2 π r 2 l. (Primary. H H = height of the wire above the plane. The auto-inductance of a coil is dependent on the mutual inductance between each current turn, the self-inductance of the coil’s wire, and the environment surrounding it. A long solenoid with length l and a cross-sectional area A consists of N1 turns of wire. One formula for inductance is as follows: Where: L = inductance. The length of wire used is also calculated. r is the coil radius. The actual bus bar design parameters may need to vary according to detailed structural requirements, working conditions etc. Many conductor properties are frequency dependent and dynamically affect electromagnetic characteristics of circuitry and systems. For each case, we use a different cable impedance formula: To calculate the impedance of a coaxial cable, we use the following formula: Impedance = 60 × ln ( D 2 / D 1) ε r. The capacitance of a pair of parallel identical wires is depended on the wire's radius, their length and the. Inductive Reactance/Admittance. It is more difficult to calculate the mutual inductance of theEaton's HCV family high current power inductors are high current ferrite inductors using secure 3 terminal mounting in a variety of sizes and inductance offerings. L is the inductance, so you need the resistance (R) and the. A sample 14 turns, half radius of 3 inches and a width of 12 inches yield an inductance of. μr is the relative magnetic permeability of the core material. N: number of turns. Additionally, since the inductance is dependent upon its material surrounding, use Table-4 to determine an appropriate "K" factor (multiplier) for the inductance. It is important to determine the characteristic impedance of a twisted-pair cable because this impedance should match the impedance. The next point is very important. The inductance for the two wire inductance might be useful in measuring the inductance for a signal and ground on a ribbon cable. 1 inch = 0,0254m=2,54cm = 25,4mm. It is important to note that in industry we can find that some differential pairs are routed this way for a strong coupling, but the actual return for the signal is on a. 1 inch = 0,0254m=2,54cm = 25,4mm. Using the Ampere-Turn Calculator to compare two coils. 5 cm apart (about one inch). Wire sizes, AWG # chosen to meet current specification. 84µH. F. ТThus, to calculate the inductance of a Tesla's flat spiral coil by the Maxwell's method. Regards JimFlat Spiral Coil. L = (0. The Reactance Calculator will calculate the inductive reactance and the capacitive reactance of a coil or capacitor, and display a live example of how to perform the calculation. Calculator of the ferrite core inductor at radio frequency. 9 r r r0----- = ln 4. EEWeb offers a free online twisted pair impedance (transmission line) calculator. Velocity factor is a fractional value relating to a transmission line’s propagation. A wire loop creates inductance. Select the. Dimensions are in meters. Enter the number of turns (windings). Studying transmission lines I am confused about a "missing" factor of two in the formula L =μ0a/b L = μ 0 a / b for the inductance per unit length of two "infinite" parallel sheets. Trace Inductance Calculator. C. Inductance Calculator. 10. Contact us today!Transformer & Inductor Tools. Yes, I'm using a flat trace circuit, in an equation for "round wires". Also, please read our Disclaimer at the bottom of the page. Install multiple ground straps at each corner of the equipment to lower the. Use DigiKey’s Ohm’s Law calculator to calculate the relationships between current, voltage, resistance, and power in simple resistive circuits. Choose units for a and W. Introduction of Coil Physical Properties Calculator. 3 Self-Inductance of a Toroid Calculate the self-inductance of a toroid which consists of N turns and has a rectangular cross section, with inner radius a,. The microstrip is designed so that its length is one-quarter or one-half of the wavelength of the signal propagating through it. The straight wire inductance of "X" is reduced by 1/10th, and the same with "Y". Inductance of a Square Loop of Wire. Use Calculator B: If you need to. Any material that has current flowing through it and produces a magnetic flux has inductance. Measure the distance between the plates, d. The formula to calculate impedance is: Where. Step 2: To calculate the resonance frequency, click the "Calculate x" button. 85 mΩ or 1. This paper presents a novel real-time power-device temperature estimation method that monitors the power MOSFET's junction temperature shift arising from thermal aging effects and incorporates the. To use this tool, just enter the diameter of the loop, the diameter of. Coil Inductance Calculator. Enter the coil diameter (form diameter + wire diameter - see diagram). 00pF to 100. C. L = (μ₀ × μr × N² × A) / (2π × d) L is the inductance per turn (in henries per turn). 2. CiteThe choices of wire are solid, stranded, foil, and Litz wire. This Coil Calculator is a professional and easy-to-use electrical tool for electrical engineers and designers. sum is used as wire length, we may confirm: the straight wire equation overestimates the inductance value l_wire=l1+l2+l3+l4+l5 AKB2014, J. For more information see About our calculators See full list on allaboutcircuits. When the length of this line is equal to λ / 4 (λ. W. For example, the electrical conductivity of copper is σ ≈ 5. Effective equivalent circuit; effective equivalent circuit: effective series inductance at the design frequency from Corum’s sheath helix waveguide formula, corrected for field non-uniformity and round. I selected a 56-pF NPO capacitor for the tuned circuit because it is in the right range, and a dozen or so were in my junk box. A microstrip is a flat conductor separated by insulating dielectric from a large conducting ground plane. Kanthal A1 Nichrome N80 Nickel Ni200 Stainless Steel 316 Titanium Custom. 17mm2. Wire Loop Inductance Description. ZL = XL ∠90 ∘ or ZL = XL∠ π 2. Effective equivalent circuit; effective equivalent circuit: effective series inductance at the design frequency from Corum’s sheath helix waveguide formula, corrected for field non-uniformity and round wire 1,3,6,7 (L_{ ext{eff,s}}) µH: effective series reactance of the round wire coil at the design frequencyAir Cored Inductor Calculator - Includes Q - Size units in mm - Computes Inductance, Q and wire length AL Inductance Calculator ### - Input two values and get the third - Inductance units: mHenrys,. Flat wire has a high winding factor of 95 %, so only 5 % is unused space in the gap between each winding compared to 30 % unused space in round wire. 2 x d2x N2) / (3d + 9l =10b) L = Inductance (in μH) d = Diameter of the inductor coil (Inches) l = Length of the indutor coil (inches) b = Diameter of the coil winding wire (inches) N = Total turns of wire. to D. Inductance Calculator. Thanks to the flat wire winding, the chokes have very compact dimensions of only 33 x 33 x 15 mm. The trace capacitance is defined with respect to the nearest ground plane in the particular configuration presented above. Planar coils are mostly used in high frequency applications and designed as tracks on a circuit board. Single layer air core inductor calculator. Refer to the bottom of the page for explanation of input variables and other notes. To estimate the mutual inductance, when the gap between the two coils is larger than wire diameter, the thick coil can be denoted by equation of planar spiral coil [ 23 ]. Overview. Wire Inductance. Use the Coil Capacitance Calculator to calculate the self-capacitance of air-cored single-layer solenoid coils, and learn how with the integrated live example. Air Core Inductor Calculator - Wide choice of coil size units - Computes Inductance with choice of units Air Core Inductor Designer - Calculator - Input in mHenrys and inches - Extensive output on a new page. This planar spiral coil inductor calculator determines the inductance of one-layer circular, square, hexagonal and octagonal planar (flat) spiral coils, which are often used in near-field communication (NFC) and radio frequency identification (RFID) tags. Solution for Let say that a flat coil of wire, having 5 turns, has an inductance L. Single Dual Triple Quadruple. For single turn coils, formula #58 from F. This search is often complex. Publisher: Cengage Learning. formulas to calculate the self inductance L. 127mm times 92 raised. Rectangle Inductance Description. Matching Pi Attenuator A two part calculator which gives ideal and preferred value resistors, showing most formulas used and a link to the others. The single layer air core coil formula is most accurate when the coil length is greater than 0. It is represented by the symbol shown in Figure 14. To use this tool, just. )ISBN: 9781337553292. D is the coil diameter in meters. Ferrite Rod Coil Calculator. Grover's Inductance Calculations - Working Formulas and Tables, is used. Matching T Attenuator Updated calculation of bandspread or tracking capacitors. 25mm). At VHF and UHF frequencies the inductance of a wire may have a great effect on a circuit. Let's calculate using 9 gauge wire with descent insulation. 1. Relative Permeability is assumed to be 1. All conductors have inductance. W. μr μ r = relative permeability. Figure 14. Microstrip Inductance Calculator Trace Width (W) in mm: Substrate Height (h) in mm: Calculate Inductance FAQs. However, in Amateur radio practice, we often deal with toroids having a square cross section, although with a. For coil inductance in Henrys: L = N 2 * µ * A / Cl. 739 althoughtheplanofcalculationhereadopteddiffersfromthat ofNiwa. Dimensional units:. Calculates the dc Resistance of a single rectangular cross section strip (or track/trace) of common conducting materials using the equation below. The inductance and inductive reactance of three single phase cables is provided by the formulas below. its self-inductance, Maxwell uses the concept—”geometric mean distance”—GDM (g), for a round wire: g = e0. Units for M are (V ⋅ s)/A = Ω ⋅ s, which is named a. To use this calculator, just enter the required values and press the "calculate" button. The calculator uses Bob Weaver's equation with round wire corrections. Where r w - cross-section radius of the wire. 6. Grover [2, pp. The loop self inductance, distributed per inch of circumference, is roughly 150nH / 6 inches, or 25nH per inch of circumference. Conductors are assumed to have zero thickness. Table 1 shows how to calculate inductance (L). Flat spiral air core coil inductor design calculator solving for inductance given wire coil number of turns, core material permeability, coil area and average coil length. 4. This calculator help for you to estimate the number of turns of your home-brew one-layer R. Table 1: Calculating Inductance (L) Equation: Parameter: Parameter Description. Dimensional units: mm mils d1 (outer diameter) = d2 (inner diameter) = N (number of turns) = L (Inductance, nH) =. Pieper X z 50u 150u 500u 50u 100u 350u 450u 200u 300u l1 l2 l3 l4 l5 P1 P2 P3 P4 P5 P6 r/u dz/mm G (S/m) L_ADS/pH l_wire/um L_straight/pH deviation z 0 200 300 300 200 0Calculate the height of the object by the length of shadow. To make things easier, R is the resistance while f is the frequency. s. 001N2D/ ( (228D/2) + 254l) Where: L is the inductance in henry's. Edge Coupled Trace Inductance Calculator. Description. 1. Parallel Wire Impedance, Inductance, Capacitance and Propagation Delay Calculator Results. Two -Wire Transmission Line The two -wire transmission line is just two long -straight wires running parallel to one another. (Copper is non-magnetic, just like air, and stores. Calculate the self-inductance of a 50. Broadside coupled traces are on adjacent planes and the return is identical to the trace in width and length. Mutual Inductance. The transmission line geometries are cross sections and the values calculated are the inductance per unit length. The inductance allows one to understand the amount of energy that can be stored in magnetic fields. Here you can see the formulas that the calculator uses to calculate the inductance. 66.