MWS Wire /
Efficient Power, High Frequency Litz Wire
Litz wire is a special type of multistrand wire engineered for carrying alternating current (AC) efficiently at high frequencies.
Litz wire is constructed of individually insulated magnet wires bunched or braided together in a uniform pattern so that each strand takes all possible positions in the cross section of the overall conductor.
MWS offers served or unserved, insulated litz wire with a single build of polyurethane, polyurethane nylon or a heavy build of polyurethane, polyurethane nylon. Additional insulation options are available on request.
MWS can help you start your litz wire journey by providing quick turnaround for small quantities in hard to source sizes for R&D or special projects while providing engineering
support. We can stay on that journey with you by seamlessly supporting the ramp up to larger wire volumes so our service grows according to your needs.
MWS not only brings many decades of experience in finding or developing optimal litz wire design, we also control the entire production process ensuring quality and performance according to each customer's specifications, from prototype to production line.
Litz Wire Technical Data
Need more info about Litz Wire? See the Data Sheet in our Tech Book.
What is "Litz"?
The term "Litz" is derived from the German "litzendraht" meaning woven wire.
What are the benefits of Litz Wire?
Litz wire offers many benefits primarily for high frequency AC applications due specifically to the controlled gauge, winding and insulation of its multiple strands.
The primary benefit of litz wire is in reducing AC losses in high frequency windings and increasing efficiency though with wire by circumventing the "skin effect," a natural phenomenon affecting the way AC current flows through a wire.
Designers can virtually eliminate the skin effect with Litz wire. The key is to choose the diameter of individual wire strands twisted into the Litz construction that are like the skin depth for the given frequency. Doing so causes current to flow through nearly the entire cross section of each wire, thus minimizing AC resistance and heat losses.
By increasing the number of wire strands, one can increase the total current available through the wire as a whole.
Circumventing the skin effect isn't the only benefit of litz wire. Closely spaced wires can also introduce unwanted eddy currents leading to similar issues with power loss and lower AC resistance. The use of insulation and a specific stranding pattern help prevent these losses.
By reducing both the skin effect and the proximity effects, litz wire can have higher efficiency and cooler operation in inductors, transformers, motors and other high frequency devices.
The Skin Effect
AC current through a single wire
AC current through multiple smaller wires
AC current flowing through a single wire conductor increasingly pushes the current toward the surface "skin" of the conductor as frequency increases. This physical phenomenon accelerates the wire's AC resistance in direct proportion to the frequency of the current. Over 98% of the current will flow within a layer 4 times the skin depth from the surface. This behavior is distinct from that of direct current which usually will be distributed evenly over the cross-section of the wire.
Common Applications of Litz Wire
There are a tremendous variety of applications for litz wire, from small lighting ballasts to large wind turbines, each with distinct technical requirements. Applications include:
- Antenna Systems
- Bottling Equipment
- Electric & Hybrid Vehicles
- EV Charging Stations
- Electric Motors
- Florescent Lighting Ballast
- Plastic Mold Injection Machinery
- Power Transformers
- Toroidal Transformers
- Solar Inverters
- Magnetic Resonance Imaging (MRI)
- Industrial Motors
- Maglev Trains
- Medical Electronics
- Microwave Transmission
- Motor Drives
- Oil & Gas Equipment
- Specialty Audio Interconnections
- Wireless Transmission Systems
- Wind Turbines
How to build your own Litz Wire
Step 1:
Determine the desired operating frequency of your litz wire.
Operating frequency is the most important question to consider when specifying litz wire. The operating frequency will determine both the litz construction and the individual wire gauge. The following table shows the recommended strand gauge versus frequency for most constructions.
| Frequency | Recommended Wire Gauge | Nominal Copper Diameter | Max DC Resistance (OHMS/1000FT) |
|---|---|---|---|
| 60 HZ to 1 KHZ | 28 AWG | .0126 | 66.37 |
| 1 KHZ to 10 KHZ | 30 AWG | .0100 | 105.8 |
| 10 KHZ to 20 KHZ | 33 AWG | .0071 | 211.7 |
| 20 KHZ to 50 KHZ | 36 AWG | .0050 | 431.9 |
| 50 KHZ to 100 KHZ | 38 AWG | .0040 | 681.9 |
| 100 KHZ to 200 KHZ | 40 AWG | .0031 | 1152 |
| 200 KHZ to 350 KHZ | 42 AWG | .0025 | 1801 |
| 350 KHZ to 850 KHZ | 44 AWG | .0020 | 2873 |
| 850 KHZ to 1.4 MHZ | 46 AWG | .00157 | 4544 |
| 1.4 MHZ to 2.8 MHZ | 48 AWG | .00124 | 7285 |
Operating frequency is the most important question to consider when specifying litz wire. The operating frequency will determine both the litz construction and the individual wire gauge. The table shows the recommended strand gauge versus frequency for most constructions.
| Select Frequency: | |
|---|---|
| Select AWG Size: |
Step 2:
Chose your Type/Construction
Type 1/Construction 1:
Type 1 Litz Wire is individual strands twisted together in a single operation.
Type 2/Construction 2:
Type 2 Liz Wire is bundles of type 1 Litz Wire twisted together. This is also known as multi-stage twisting.
Step 3:
Choose Served or Unserved
Served Litz Wire is wrapped with nylon to provide extra mechanical strength to protect the individual strands from scratches or abrasion during handling, processing, or installation.
Litz wires are often insulated with an overall single or double wrap, (or serve) of nylon textile that affords additional abrasion resistance and a space factor in the winding.
Unserved Litz Wire lacks the nylon protection and consists only of the individually insulated wire strands.
Most popular Litz Wire configurations offered by MWS
7-28 HPN Unserved
Litz Wire
20-30 SPNSN Served
Litz Wire
40-38 SPNSN Served
Litz Wire
50-34 SPNSN Served
Litz Wire
70-36 SPNSN Served
Litz Wire
75-40 SPNSN Served
Litz Wire
100-44 SPNSN Served
Litz Wire
150-46 SPNSN Served
Litz Wire
1000-48 SPNSN Served
Litz Wire
Need a Litz Wire expert? Contact Us!
With over fifty-five years of experience in the wire business, MWS is ISO9001: 2015 compliant and has a built solid reputation for same day shipment from our inventory or producing a wire to meet just-in-time schedules. And if we don't have it, we can manufacture litz wire according to customer requirements.
Looking for something specific?
We probably have it in stock. If we don't, we can make it faster than you'd think!
Why Choose MWS?
Quick and Right Answers.
We invest heavily in our customer service and engineering team so that we can give you the right answers and the most effective customized solutions. Our success, as well as our very purpose, is directly linked to the long-term satisfaction of our customers using our wire products.
Unrivaled Availability, Low Minimum Order Quantity, and Quick Delivery.
MWS has one of the largest inventories of stainless-steel wire and other wire products. We provide wire from 1/4lb to 50lb spools. Ninety percent of our stock orders go out within a week. Short production runs and quick turnarounds are our specialty.
Pre-cut Wire Lengths and Other Custom Orders.
We can provide straight wire cuts from one inch to 6-foot lengths holding the tolerances you require for your specific application. Need shaped wire? We have a variety of special shapes including square wire, flat wire, and ribbon wire. Special coatings and finishes are available as well.
Headache Free Compliance Documentation.
Let us help you satisfy your customer's needs for clear and comprehensive compliance documentation including RoHS, REACH, DFARS, MADE IN USA, USMCA, etc. Chemical and physical testing reports are also available upon request.
Let Us Manage Your Inventory for You.
With 40,000 sq. ft. of warehouse space and thousands of products in stock, inventory management is our specialty. It doesn't have to be yours. Whether it's same day shipment from inventory or producing a wire to meet just-in-time schedules, we can get what you need when you need it. Ask about scheduled shipments synchronized to work with your inventory control, JIT, or Kanban system.