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7. Improve the connection between the receptacles and the wires

Soldering receptacle will be better than any other ones. It's stable and lasting for carrying the high current.

Insertion high current probes

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Larger force contact to soldering pad

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Serrated tip to soldering pad

Rare metal plated layer

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Star tip to via

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Flat tip to golden pad

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Round tip to golden pad

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High current test probe not burned

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Flat Contact to dip

How To Test High Current With Probes

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Round Contact to soldering pad

Insertion receptacle for wire inserting, it is not so strong

With the rapid development of integrated circuits, many electrical and automotive applications have adopted high-current functions. How to safely and effectively test this type of product is becoming a new challenge.

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Sharp Contact to soldering pad

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Flat Contact to soldering pad

How to improve the high current probe's effectiveness on high current testing

1. Increase the contact area between probes and DUTs

Increasing the contact area is making the current crossing area larger that enlarge the channel of the electric charges. Here are some suggestion for better contact between probe tips and DUTs.

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Standard force contact to soldering pad

4. Create more space for heat dissipation

Heat dissipation is the issue after heat generating, when the current is passing over the conductor, the conductor will generate the heat, the dissipation and generating ratio is less than 1, the dissipation will reduce the burning issue rate. We should use the disipated the fixture boards to install the probes and sockets.

5. Pay attention to the important influence of continuous current and peak current

Pay more attention on the continuous current and peak current, the high current probes face the tough power test situation, continuous current is a persistent electric signal. So they are very important.

6. Improve the connection between probes and receptacles

What we do is to make sure more tighter much better, screwing and insertion are both can be tighten between the probes and receptacles.

Here is the link for high current probes selection Click Here

2. Increase the contact spring force.

It's not useful to apply the light force probes, for high current we need over-estimate 25% compared to standard probes. The puncture depth of larger force contact is deeper than the standard force contact see as Fig.⑭ and Fig.⑮. So obviously the contact of Fig.⑮ is more stable and more contact area between the soldering pad and probe tip.

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Crown Contact to dip

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More contact points

Click to High Current Probe List

3. Improve the materials and structural characteristics of the test probes

Materails to high current spring probes are very significant. Compared to the standard contact probes, high current version ones are made of high conductive materail with uncommon metal plating treatment to ensure the high current carry aptitude.

Structural design increases more and more extremly contact inside of the probe to carry high current stablely.

Screw high current probes

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Few contact points

And we also developed high current test probes which are usually used to test large-scale charging and discharging equipment.

Seeing from the parameter characteristics, the current value to pass over is the most important performance on high current test probes. Physically speaking, a test probe will generate heat when it is carrying the current as a conductor, We can simply consider the probe can continue to work at the high current that passing over the test probe and doesn’t burn the probe.

The measure of heat is expressed by the temperature, the high current probe can test the value of high current is determined by that the high current probe bear the temperature and still working smoothly. We can test the high current with the temperature by the device.

Why we need to choose a spring contact test probe for high current test conductor?

Why not use a copper bar to contact?

Because compared to the copper bar( a rigid lead), the spring contact test probe will safely protect the DUT with a durable cycles under the automatic test fixture.

So to a high current test probe, the spring is the key point component, usually the spring will be made from stainless steel wire or music wire, both of those two wires are made of carbon( a high resistance ratio element), For example, The resistivity of stainless steel reaches(20℃): 0.73Ω·m. In contrast, the resistivity of copper is only 1.75 × 10-8 Ω·m. if we straighten a stainless steel wire made spring and test it, the resistance is high over 40Ω. So if the current pass from the spring to the barrel and this caused fatal influence. the spring will be burned and stuck. The probe now will become a rigid pin and break the DUT in high probability.

Generally, the thin spring wire will burn black or melt at a high temperature 120°C. This is the biggest challenge of the high current test probe.

So we need to consider.

The internal structure design of the high current probe affects the aptitude of pass high current.
The heat dissipation problem of the high current probe will affect the performance on carrying the high current.

We have to pay attention to a lot of problems in the high current test process

1.The high current probe is not fully contacting to the DUT

Fully contact to the DUTs is very important to very contact test, the means the conductor can pass the signal or current from the DUT to testers through the test probes, here will illustrate some situation that using the wrong probe tips.

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Serrated tip to soldering pad

2. The spring probe force is weak

The spring probe force is pressing power of the test probe, it generates the power to puncture or contact tightly to DUTs, so helping the probe tightly contact the DUTs is very important.

3. The heat dissipation effectiveness of the fixture board is not good.

A probe is a conductor to contact the big current DUT, will dissipate the heat during the big current test process. The heat dissipation is not good that will effect the high current test resault, heat accumulation will cause the spring burn out. That is why heat dissipation so important.

4. Misunderstanding between continuous current and peak current.

We misunderstood the continuous current and peak one,continuous current is supplied continuously as a stable value. it is very different from a peak current, that appears a highest current value during the power suppling. They are abosulutely different consideration on high current probe design.

5. Adopted bad test probe receptacle connection method.

6. It's wrong to select the normal test probe to test high current DUTs.

See Fig.⑥and Fig.⑦, the standard contact probe will be burned when it is used in high current test, but not burn of high current test probe, the spring is burned black in Fig.⑥.