Many believe that taking a “least cost” approach is best in sourcing a supplier for the building of their custom cable assembly. What does that approach guarantee? Well, it guarantees a low price but does it guarantee on time delivery of a high quality product? Unfortunately, when accepting a low price as the main driver for supplier selection you usually get what you pay for, a great price, but, also long lead times and a product of marginal quality. Custom assemblies are usually unique in their design and are quite involved when it comes to design and assembly. To effectively source a supplier to build your unique custom cable assembly you should consider many factors on the way to your final decision. These factors are:

• Reputation
• Experience
• Ability to provide prototypes
• Willingness to provide samples for test
• Ability to adjust to design changes quickly
• Ability to meet deadlines
• Ownership and financial stability

When you start your search make sure you look for companies who have a reputation of supplying quality products. You will avoid unnecessary risks by limiting your search to those who know how to deliver quality products. Make sure your selection originates from only those with a great reputation for quality. This will provide a great foundation for making the proper supplier selection. Within this group of potential suppliers find out which have experience in building and supplying cable assemblies. If you are looking for complex harnesses make sure you look for those with harness expertise. If you are looking for more simplistic assemblies such as grounding assemblies, for example, go with a supplier who has expertise in supplying quality grounding assemblies.

When it comes to having a uniquely designed custom cable assembly it is always best practice to have a prototype made from the original specification for your consideration. This will allow your engineer(s) and possibly your customer a chance to review the original assembly build to insure it meets everyone’s expectations. Product modifications can usually be spotted at this time. Very few first articles are perfect right from spec. If a potential supplier will not agree to provide a prototype, move on and find a supplier who will.

Once a final version of the prototype is established it may be necessary for a number of samples to be built for testing purposes. If this is the case for your assembly make sure you find a supplier who is willing to provide test samples of the assemblies you need. Testing is usually necessary to insure the assembly can perform as expected from the prototyping phase. Like prototyping this too can lead to additional design changes. This is a critical step in the process of cable assembly development. Like prototyping, if your prospective supplier is not willing to provide samples, consider moving on with your selection.

Another important consideration is your prospective supplier’s ability to ship on time and meet deadlines. We’ve all been involved with projects that are held up due to longer than expected lead times. Yes, sometimes things happen that are beyond your control, but, many suppliers eager to get the business often quote shorter lead times simply to win business. When this occurs, nobody wins as lead times often stretch well beyond project deadlines bringing the project to a halt. During your selection process ask your prospective supplier how they quote lead times. Additionally, always ask what their on-time delivery performance is for the type of assembly you are sourcing.

Finally, supplier ownership and financial stability is key for a prospective supplier producing a critical piece of your project. Why take the risk of having your supplier potentially struggle to buy parts and raw materials for your assembly; or even worse, suspend operations altogether leaving you at square one. Nobody wants to be in this position so make sure you check out your prospective supplier’s financial credentials before entering into a contract.

It’s not as easy as you might think to choose a supplier to manufacture your customer cable assembly. Make certain you do your due diligence. This will allow you to make the appropriate selection for a supplier perfect for your project. Although this may take some time up front, it is far better to take the time to learn rather than suffer the consequences of poor judgement after it’s too late.

Interested in what we do? Click the button below to see our custom assembly capabilities. 

It may seem like common sense, but it’s important to make sure your grounding and bonding straps are working properly. It is essential that your clips are making a good connection. 

• Ensure your clips are clean and clear of debris.
• Check to see that you are getting a solid metal-on-metal connection. If there is paint on the surface the clips connect to, make sure the clips are breaking through that paint.
• Inspect your grounding equipment regularly and take measurements with a multimeter to ensure there is a low resistance.
• Replace any clips or straps that are too rusted to perform properly

Remember that bonding and grounding serves an important safety purpose, and regularly checking up on the grounding and bonding straps can prevent sparks and explosions.

To read more on static electricity in industry, check out our whitepaper here

If you are interested in custom-made grounding or bonding equipment, you can see our capabilities here

Static Electricity and Fluids

Some fluids that are flammable and combustible (like fuel and other chemicals) can be a static electricity hazard depending on how conductive they are.

As fluids move through pipes or a hose they can build up a static charge because they cannot conduct electricity unless the pipe is grounded. A spark can result if enough of a charge has built up, and an explosion can occur. Solvents that are water soluble like alcohol generally do not build up static electricity because the water is conductive. However when the liquids are transferred into a non-conductive container like glass or plastic, a charge can build up because the plastic or glass does not adequately dissipate the charge in the solvent.  Other factors are the flash point of the liquid, vapor pressure, air humidity, elevation, and temperature. For example, vapor levels in the air around the container will be higher in a hot room or on a hot day rather than on a cold day.

At high elevations the air pressure is lower and a solvent can boil and spark at a lower temperature

Some fluids that are flammable and combustible (like fuel and other chemicals) can be a static electricity hazard depending on how conductive they are.

As fluids move through pipes or a hose they can build up a static charge because they cannot conduct electricity unless the pipe is grounded. A spark can result if enough of a charge has built up, and an explosion can occur. Solvents that are water soluble like alcohol generally do not build up static electricity because the water is conductive. However when the liquids are transferred into a non-conductive container like glass or plastic, a charge can build up because the plastic or glass does not adequately dissipate the charge in the solvent.  Other factors are the flash point of the liquid, vapor pressure, air humidity, elevation, and temperature. For example, vapor levels in the air around the container will be higher in a hot room or on a hot day rather than on a cold day.

At high elevations the air pressure is lower and a solvent can boil and spark at a lower temperature.

Grounding and Bonding

Electric sparks can result from transferring a liquid from one metal container to another as a result of static electricity buildup.  To prevent sparks and electrostatic buildup, it is necessary to bond or ground the containers before pouring. Bonding is making an electrical connection with metal clamps and a wire between all the containers which will equalize the electrical potential between the containers. Bonding containers establishes a metal-on-metal connection between two or more containers.

Grounding is attaching a wire from the container to an already grounded object which will cause the static electricity to run into the ground. 

Both methods will guarantee that there will be no difference in electrical potential between the containers pouring and receiving the liquid. Bonding the containers and then grounding one of them will drain off the static charges from everything and will prevent static discharge and sparks.

For more information on static electricity and grounding, read our whitepaper. 

Mueller provides a huge selection of components used for medical devices

These products include: 

• Wires and Connectors for Home and Hospital Devices
• Plungers for Cardiac Procedures
• Components for Medical Kits and Trays
• Hooks and Clips for Hanging IV bags
• Clips and Insulators for Medical Monitors

Some examples of where our products are being used:

• A microscopic connection on the cable end of Diaphragm Pacing Regulators
• Pacemaker Kits
• Medical Monitors
• Pericardiocentesis Kits
• Home Galvanic Units

Please view our catalog and have a look at our most popular items and contact us for a quote. If you don't see something, just ask (we probably have it!). 

We make a really great assortment of cables here at Mueller, and one of the things we really excel at is doing custom bulk orders. We have a huge inventory of wires and terminations with custom over molding capabilities, and sourcing whatever we need for a project. We also have a great production team of 10 people who specialize in building custom assemblies right here in Ohio, engineering support and helpful staff. We can design and build exactly what you need.  

We are already known for manufacturing high quality grounding and bonding cables, but we can make other electrical cables and assemblies as well. So if you need something and don't see it as part of our ready-made selection feel free to talk to us and see if we can create what you need and save you money in the process. If you currently order parts and make cable assemblies in-house at your facility, we may also be able to save you money and time on production. In fact, our customers have saved as much as 25% by sourcing their cable assemblies from us. 

When people and businesses contact us to design something custom, we want to make the process easy and painless.

The design process can vary depending on the customer's need. Some people know exactly what they want (or have a prototype that they just want us to quote on) and others may need some guidance and recommendations to accomplish their goal. 

When you contact us, we will discuss your application and your thoughts on what you think the design could be. If you already have specs and sketches ready, that is very useful to us, but it isn't required. If you have any challenges we can go over solutions and ideas for your consideration. Then we'll put together a prototype and send it to you for a test. From there we can either modify the prototype or quote you on manufacturing the part. 

We look forward to working with you. Click on the button below to reach out to us and get a no-obligation quote. 

If you are in need of a wire or cable assembly that is custom made for your specific requirements, there are a number of options to consider. On the surface it's pretty simple - You have a wire, and then something on the ends of the wire (or not). But there are tons of options to customize and get it just right for what you need. 

If you are not 100% sure of your needs, we are here to help. Click the button below and fill out the form on the page to consult with our team or get a quote. 

From electrical design to maintenance, engineers must determine what electrical clips (also called alligator or crocodile clips) are best suited for their project.

These clips can range from small to large, be made of a wide range of materials, come in various jaw types, handle wide ranges of electrical current and can be certified for safety by being UL-listed.

With such a wide range of options, there are many factors to come into play when selecting clips

Amperage

Typically, electrical and electronic clips are rated by their ability to handle varying levels of current which is measured in amps so you will need to know the amount of current that you will be dealing with.

Once you know the level of current, you can calculate the amperage rating required for the clip.

The formula for Amps is Watts divided by Volts.

The amperage capacity of a clip is typically listed right on the clip itself.

Generally speaking, larger clips are able to handle more current, however, that doesn’t always mean a larger clip is always necessary. Solid copper clips are able to handle higher levels of current and carry a higher amperage rating than its zinc plated steel counterpart. For example, a heavy duty clip for battery and test work applications may be rated at 50 AMPS for the zinc-plated steel version while the same sized clip made in solid copper is rated at 100 AMPS. 

Clip Jaw Types

Another factor to be considered is how the clip needs to connect to its point of contact. Clips come in all shapes and sizes with different types of jaws and teeth. Clip jaws can come flat nosed, with teeth, or wrap around a terminal or pipe. Some clips have flat wide noses with teeth and others may be rounded to grab round objects. Deciding which clip to use is dependent of what the clip is grabbing on to and will vary per application.

Flat nosed clips are typically used in paint grounding.

Smaller clips with teeth are used for test and measurement.

Larger clips that wrap around will provide a strong grip and may penetrate a layer of paint. These are often used for battery charging and grounding.

Flat wide jaws with teeth are perfect for grounding and work holding uses.

There are, however, a tremendous number of applications for all types of jaw styles. As technology progresses, so do clips, with new types being invented all the time.

For more on different types of clips and what they are used for, check out our guide to clips. 

Clamp Pressure

Clip grabbing strength, or clamp pressure, is another factor to take into consideration when selecting the right clip. Clamp pressure usually increases as clip and spring size increase. Larger clips will have a stronger grip than smaller clips. In some cases clips can be made to have less clamp pressure which can be helpful for delicate or detailed situations.

Clip Size

There are many different sizes of clips and size can sometimes be important to consider. One determining factor is if there is a space requirement. Another factor is the amount of clamp pressure required, as well as the amperage rating needed.

Some clip sizes are determined by the application itself as there may be limited space where the clip can fit.  Naturally if you have a small space then you probably will pick a smaller clip.

Higher amp rated clips tend to lend themselves to uses where a tight space is not a concern. The environment may dictate what a clip size may need to be as the larger clips tend to hold up better in harsh environments such as electroplating.

There is no real guideline on determining what clip size to use. Some engineers try to make sure they have the right amperage rating, clamp pressure and jaw type in the smallest package possible to reduce the possibility of “overkill” and inflating costs unnecessarily. Other engineers go one step up in size to ensure all bases are covered. In most cases, several different sizes of clips are used in various prototypes to test first hand which clip size is best.

Material

Clips are made with zinc or nickel plated steel, stainless steel, solid copper, gold plating and even nickel-silver.

Generally speaking, zinc or nickel plated steel is the most cost effective material used in clips.

Solid copper clips can handle higher levels of current better than similarly sized clips made of other materials.

The environment where the clip will be used can determine what material should be used for a clip. For example, stainless steel clips can withstand marine, caustic or corrosive environment better than other materials. Other clips that can be used in marine environments are marine rated clips which are made of solid copper for greater connectivity but with moisture resistant springs which significantly extend the life of a clip used in the vicinity of water and salt.

We did an experiment to show how marine and stainless steel clips hold up compared to other clips. Read about it here. 

Read about different metal finishes for clips here.  

Safety

Safety is always a consideration when working with electrical components, but some more than others.

For instance, when using clips and cables for grounding and bonding, an exposed clip works just fine, while other applications it may call for an insulated clip.

UL Listed products are certified for safety. UL Listed clips and connectors are certified to insure that human hands cannot come in contact with the conductors while in use and energized.

Other applications may call for clips to be utilized in a “hands free” environment which means that the clips are not manipulated or touched while a circuit is energized. The clips still need protection from touching each other or other parts which could interfere with the electrical signal or cause a short, so insulators or “boots” are placed over the clips to protect them.

For help in selecting clips with different features, try our clip selector.

Underwriter Laboratories has set the standards for product safety and has a through certification process. Mueller Electric is proud to provide UL Listed items and this blog post will provide some insight into what it means for something to be UL listed.

Underwriter Laboratories (UL) is the best known, largest and oldest independent testing laboratory in the United States and a world leader in product safety testing and certification. They set safety standards for different product categories and test products to make sure they meet those standards.

UL tests over 19,000 different products annually, ranging from consumer electronics, alarms and security equipment, to lasers, medical devices and robotics. 

There are two types of UL products that Mueller has. One is a listed product that is sold to an end consumer, and the other is a UL listed component that is meant to be used as part of other UL listed products.

A product that is UL listed has been thoroughly tested for safety and sometimes includes features that make it safer than similar products. For example, the Mueller BU-65 alligator clip is fully insulated and includes a guard near the teeth to prevent fingers from accidentally touching the teeth and has a fully shrouded connection. 

Mueller’s UL listed test probes and banana connecters also have a finger guards for safety, while the BU-6161-M-@ test lead has shrouded banana plugs at each end. These fully shrouded plugs ensure there is no exposed metal.

UL inspects Mueller's facilities on a quarterly basis to ensure the products continue to be manufactured to the high safety standards that they were originally reviewed under. 

Check out our high voltage test & measurement page.

For a general overview of clips, check out our guide to clips.

 Learn more about banana connectors here. 

Raw uncoated steel can easily oxidize and corrode/rust over time when exposed to various environmental conditions and/or corrosive applications.  Sometimes it’s necessary to use different metals for electronic parts that will not corrode or to plate them with different metals that will provide protection against corrosion. Different metals are useful for different applications, although sometimes it’s also a matter of aesthetics.  

Stainless Steel

Stainless steel remains stainless – meaning it does not rust or corrode because of the interaction between its alloying elements and the environment. It forms its own film layer on the outside of the metal that protects itself from attack by the elements. The downside to stainless steel for electronic parts is that it is difficult to solder to so it’s not always an ideal metal for all situations.

Stainless steel is generally silver colored but it can be plated/tinted to various colors.

Gold Plated Steel

Gold has relatively high electrical conductivity and stable contact resistance. It is one of the most conductive of all metals.

Electroplating gold increases the substrates resistance to corrosion. Gold is the most nonreactive of all metals. Gold will generally not rust/oxidize in the outdoor elements. Due to cost, gold is normally plated very thin on connectors.  This along with gold being so soft, allows it to wear off from the connector rather easily which exposes bare steel. Also, if the connector is used to connect or disconnect a live circuit above an amp or so, then the plating will burn off the contact area in a short time.  Generally, gold is used for connectors where low resistance is important and that do not see many mating cycles.

All of these factors makes gold plating a popular choice for electrical components such as semiconductors and connectors. The downside to gold plated parts is the cost, as gold is not an inexpensive material.  It is also soft and easy to wear/burn off.

Nickel Plated 

Nickel plating provides a bright finish and can harden the surface of a substrate which can increase resistance to wear and corrosion. There are different types of nickel finishes that can range from dull silver to bright and shiny to black. Nickel’s corrosion protection is used across a wide range of industries including heavy equipment, oil & gas, power transmission & distribution, automotive, and marine.

Copper Plated Steel

Copper is an excellent conductor of electricity. All-copper and copper electroplating is a preferred metal finishing choice in the manufacturing of electronic circuit boards, semiconductors, and other electronic parts and components. Copper is an excellent conductor of electricity. All-copper and copper electroplating is a preferred metal finishing choice in the manufacturing of electronic circuit boards, semiconductors, and other electronic parts and components.   Circuit boards, semiconductors and most electronic parts use solid copper, not copper plating.  Copper plating is not always a good functional choice, but it does have an aesthetical appeal.

Check out our Guide To Clips for more information on alligator clips. 

When selecting a clip for an application, there are often environmental considerations that may affect the clips over time. One of the toughest environments is a marine environment where there is a lot of moisture and salt which corrodes many types of metal. 

I performed an experiment with our 46 series clips to see how well the marine clip actually withstands a salty marine environment. 

We already know that Stainless Steel and Copper both hold up in a marine environment pretty well, but how well? One of the primary uses for clips is for safety and electrical/grounding applications, so it's important that the clip holds up well and works the way it's supposed to. Clips that cannot hold up in a marine environment would need to be replaced often, which also adds a cost consideration. 

Stainless Steel and Copper are both excellent choices for a marine environment and the main difference when selecting a clip that is right for you would be if you need to solder to the clip. Stainless steel is nearly impossible to solder a wire to. Copper is easily solderable. In most cases the 46M (M for Marine) would be the clip of choice because of that soldering capability. 

Now onto the experiment!

The Setup:

I took 1 of each of the following clips and I put them in a plastic ziploc bag partially filled with with salt water to simulate a wet salty environment with both water and air. Salt water corrodes metal five times faster than fresh water does and the salty, humid ocean air causes metal to corrode 10 times faster than air with a normal amount of humidity.

I documented the changes in the clips over time with exposure to that environment. 

An introduction to the different clips taking part in this experiement:

BU-46A :  Copper Plated Steel with a Steel Rivet and Spring

BU-46C : Solid Copper with a Steel Rivet and Spring

BU-46X : Stainless Steel with a Stainless Steel Rivet and Spring

BU-46M :  Copper with a Stainless Steel Rivet and Spring

Note - these clips can also come with insulators. For the purposes of this experiment, none of the clips are used with insulators.  

Here's an image of the clips before they go into their salty environment - tops and sides. 

Day 0 (January 4th 2018): the clips were placed in their respective ziploc baggies with salt water. 

Day 1: There are some changes already! 

The 46C bag shows green discoloration in the water from the salt reacting with the steel rivet, but the clip itself looks ok. The water in the 46A clip bag has taken on a slightly yellow tinge. No change in the 46M or 46X. 

 Day 5:

The bag with the BU-46C is pretty funky looking from the steel spring and rivet corroding. The BU-46A is also looking funky but not quite as much.  The BU-46M has a slight green tinge to the water as expected with copper, but the stainless steel rivets are not corroding. The BU-46X is looking fine!