Clip leads made with fake wire

Summary

In this video, the creator tests cheap clip leads from China, focusing on their high resistance due to poor crimping and the use of low-quality materials like iron instead of copper. Through resistance measurements and heating tests, it’s shown that iron wires result in inefficient connections, causing higher resistance and heat buildup. Despite using thin wires and copper coatings, these clip leads are unsuitable for precision tasks. The creator emphasizes the importance of checking connections and suggests that such clip leads are only appropriate for low-power applications like powering a mouse.

Takeaways

• 😀 Cheap clip leads often have high resistance due to poor crimping and low-quality materials.
• 😀 Soldering the clip leads can help reduce resistance, but the wire's inherent quality remains a concern.
• 😀 Thin wires, commonly used in cheap clip leads, can cause excessive heating when current passes through them.
• 😀 Resistance measurements are crucial for identifying poor-quality wires, with some clip leads showing resistance as high as 308 milliohms.
• 😀 Homemade clip leads with thicker wires perform significantly better, with much lower resistance (19 milliohms).
• 😀 Using a power supply to run 1 amp of current through various leads helps identify which wires get warm due to high resistance.
• 😀 Infrared thermometers and voltmeters are useful tools for measuring heat buildup and voltage drop across clip leads.
• 😀 The actual resistance of wires often deviates from theoretical calculations due to the presence of low-quality materials like iron.
• 😀 Iron is commonly used in cheaper clip leads and wires, resulting in much higher resistance than copper.
• 😀 A magnet test is an effective way to confirm whether a wire is made of iron or copper, as iron will be attracted to a magnet.
• 😀 Despite the subpar performance of some Chinese-made clip leads, it's still important to understand why they fail and how to choose better alternatives.

Q & A

Why is it important to check the resistance of clip leads?

Checking the resistance of clip leads helps identify any potential issues with the connections. Poorly crimped or low-quality leads can have higher resistance, leading to inefficient performance or overheating, which can negatively impact the circuit or device they're connected to.

What problem does poor crimping of clip leads cause?

Poor crimping results in a high contact resistance. This happens because the wires are simply folded over and squeezed shut, rather than being properly joined. This increases the overall resistance and reduces the efficiency of the connection.

What did the user find when measuring the resistance of the clip leads?

The user found that the resistance of several cheap clip leads was high, often ranging from 293 milliohms to 316 milliohms, which is much higher than desired. This indicates that the leads were poorly made, with high resistance due to either poor connections or inferior materials.

Why does the resistance of some wires cause them to heat up?

When current flows through a wire, the resistance causes some of the energy to be converted into heat. If the wire has high resistance, more energy is lost as heat, causing the wire to warm up. This is particularly noticeable in low-quality wires with thin conductors.

What did the user discover about the materials used in cheap clip leads?

The user discovered that many of the cheap clip leads were made of iron instead of copper. Iron has a much higher resistance than copper, which increases the overall resistance of the wire and makes the leads less efficient for electrical connections.

How did the user confirm that the clip leads were made of iron?

The user confirmed the presence of iron in the clip leads by testing them with a magnet. Iron is magnetic, so when the magnet attracted the wire, it indicated that the wire was made of iron rather than copper.

What is the main issue with using iron instead of copper in clip leads?

Iron has a resistance about six times higher than copper, which leads to increased power loss, overheating, and reduced performance in electrical connections. Copper is preferred for its lower resistance and better conductivity.

How did the user attempt to calculate the expected resistance of the wire?

The user measured the wire's diameter using a micrometer and calculated its cross-sectional area. They then used known resistivity values for copper and iron to estimate the expected resistance. However, they found the actual resistance to be higher than their predictions, indicating the presence of iron.

What are the practical implications of using clip leads with high resistance?

Using clip leads with high resistance can cause excessive heating, inefficient power delivery, and potential damage to connected devices or components. For sensitive electronics or higher-power applications, low-resistance leads are crucial to ensure proper functionality and safety.

Can cheap clip leads still be useful despite their high resistance?

Yes, cheap clip leads can still be useful for low-power applications where resistance and heat buildup are less of a concern, such as powering low-current devices like mice. However, for more demanding tasks, it is advisable to use higher-quality, low-resistance leads made from copper.