Stairs.  Entry group.  Materials.  Doors.  Locks.  Design

Stairs. Entry group. Materials. Doors. Locks. Design

» Do-it-yourself tester probes. Measuring probes for a multimeter: review of budget and professional options High-quality probes for a multimeter

Do-it-yourself tester probes. Measuring probes for a multimeter: review of budget and professional options High-quality probes for a multimeter

Every owner of a Chinese multimeter DT830 and similar models must have encountered some inconveniences during operation that are not visible at first glance.

For example, the battery constantly drains due to the fact that they forgot to turn the switch to the off position. Or lack of backlighting, impractical wires and much more.

All this can be easily modified and the functionality of your cheap multimeter can be increased to the level of individual professional foreign models. Let's consider in order what is missing and what can be added to the operation of any multimeter without special capital costs.

Replacing multimeter wires and probes

First of all, what 99% of users of cheap Chinese multimeters encounter is the failure of low-quality measurement probes.

Firstly, the tips of the probes may break. When touching an oxidized or slightly rusty surface for measurement, the surface must be lightly cleaned to ensure reliable contact. The most convenient way to do this is, of course, using the probe itself. But as soon as you start scraping, at that moment the tip may break off.

Secondly, the cross-section of the wires included in the kit also does not stand up to criticism. Not only are they flimsy, but this will also affect the error of the multimeter. Especially when the resistance of the probes themselves plays a significant role during measurements.

Most often, a wire break occurs at the connection points at the plug-in contact and directly at the soldering of the sharp tip of the probe.

When this happens, you will be surprised how thin the wiring inside is really.
Meanwhile, the multimeter must be designed to measure current loads up to 10A! How this can be done using such a wire is not clear.

Here are real data on current consumption measurements for flashlights, made using standard probes included in the kit and using homemade probes with a cross section of 1.5 mm2. As you can see, the difference in error is more than significant.

The plug-in contacts in the multimeter connectors also become loose over time and worsen the overall resistance of the circuit during measurements.

In general, the unequivocal verdict of all owners of DT830 multimeters and other models is that the probes need to be modified or changed immediately after purchasing the tool.

If you are the lucky owner lathe or you have a familiar turner, then you can make the probe handles yourself from some insulating material, for example pieces of unnecessary plastic.

The tips of the probes are made from a sharpened drill. The drill itself is a hardened metal and can be used to easily scrape off any carbon deposits or rust without the risk of damaging the probe.

When replacing plug-in contacts, it is best to use the following plugs used in audio equipment for speaker sockets.

If you really are on a collective farm or there are no other options at hand, then as a last resort you can use ordinary contacts from a collapsible plug.
They also fit perfectly into the connector on the multimeter.
At the same time, do not forget to insulate the ends that will stick out outside the multimeter, in the places where the wires are soldered to the plug, with a heat pipe.

When it is not possible to make probes yourself, the body can be left the same, replacing only the wires.

In this case, three options are possible:


After replacement, such wires will very easily be collected into a bundle without getting tangled.

Secondly, they are designed to withstand a huge number of bends and will break no sooner than the multimeter itself fails.

Thirdly, the measurement error due to their larger cross-section compared to the original ones will be minimal. That is, there are continuous advantages everywhere.

Important note: when replacing wires, you should not try to make them much longer than those that came with the kit. Remember that the length of the wire, as well as its cross-section, affects the overall resistance of the circuit.

If you make long wires up to 1.5 m, taking into account all the connections, the resistance on them can reach several ohms!

Those who do not want to do homemade products can order ready-made, high-quality silicone probes with many tips on AliExpress.

To ensure that new probes with wire take up minimal space, you can twist them into a spiral. For this new wire it is wound around the tube, wrapped in electrical tape to secure it, and the whole thing is heated with a hair dryer for a couple of minutes. As a result, you get this result.

In a cheap version, this trick will not work. And when used for heating construction hair dryer insulation may even float.

Refinement of the multimeter mount

Another inconvenience when taking measurements with a multimeter is the lack of a third hand. You constantly have to hold a multimeter in one hand and use the other to work with two probes at the same time.
If measurements take place at your desk, then there is no problem. Put the tool down, free your hands and work.

What should you do if you measure the voltage in a panel or in a distribution box under the ceiling?

The problem can be solved simply and inexpensively. In order to be able to mount the multimeter on a metal surface, on back side device using hot glue or double-sided tape, glue ordinary flat magnets.

And your device will be no different from expensive foreign analogues.

Another option for inexpensive modernization of a multimeter in terms of its convenient placement and installation on a surface for measurements is manufacturing homemade stand. To do this, you only need 2 paper clips and hot glue.

And if you don’t have any surface nearby where you can place the tool, what should you do in this case? Then you can use an ordinary wide elastic band, for example from suspenders.

You make a ring out of an elastic band, pass it through the body and that’s it. Thus, the multimeter can be conveniently mounted directly on your hand, like a watch.

Firstly, now the multimeter will never fall out of your hands again, and secondly, the readings will always be before your eyes.

Caps for probes

The spikes at the ends of the probes are quite sharp, which can hurt you. Some models come with protective caps, some do not.
They also get lost quite often. But in addition to the danger of pricking your finger, they also protect the contacts from breaking when the multimeter is in a bag mixed with another tool.

In order not to buy spare ones every time, you can make them yourself. Take an ordinary cap from a gel pen and lubricate the tip of the dipstick with any oil. This is done so that the cap does not stick to the surface during the manufacturing process.

Then fill inner surface hot glue the cap and place it on the sharp tip.
Wait until the hot glue hardens and calmly remove the resulting result.

Multimeter backlight

A function that the multimeter lacks in poorly lit areas is display backlighting. Solving this problem is not difficult, just apply:

Make a hole in the side of the housing for the switch. Glue the reflector under the indication display and solder two wires to the crown contacts.
They supply power to the switch and then to the LEDs. The structure is ready.

The final result of a homemade modification of the multimeter backlight will look like this:

The backlit battery will drain much faster, so be sure to turn off the switch when natural light will be quite enough.

Replacing the crown in a multimeter with a lithium-ion battery from a phone

IN last years It has become very popular to remake a multimeter by replacing the power supply from the original crown with a lithium ion battery from cell phones and smartphones. For these purposes, in addition to the battery itself, you will need charging and discharging boards. They are bought on Aliexpress or other online stores.

The overdischarge protection board for such batteries is initially built into the battery in its upper part. It is needed to prevent the battery from being discharged beyond its nominal value. acceptable standards(about 3 Volts and below).

The charging board does not allow the battery to be recharged above 4.2 Volts (link to aliexpress).
In addition, you will need a board that increases the voltage from 4V to the required 9V (link to aliexpress).

The battery itself fits compactly on the back cover and does not interfere with its closure.
First, the output voltage on the boost module must be set to 9 Volts. Connect it with wires to a multimeter that has not yet been converted and use a screwdriver to unscrew the required value.

You will have to make a hole in the case for a micro or mini USB charging connector.

The boosting module itself is located in the place where the crown should be.

Be sure to ensure that the wiring from the module to the battery is of the required length. In the future, this will allow you to easily remove the cover and, having halved the body, carry out an internal inspection of the multimeter if necessary.

After placing all the parts inside, all that remains is to solder the wiring according to the diagram and fill everything with hot glue so that nothing moves when moving the device.

It is advisable to fill not only the body with hot glue, but also the contacts with the wires in order to extend their service life.

A significant drawback of such a multimeter on a lithium-ion battery is its operation, or rather not operation, at subzero temperatures.

Once your multimeter sits in the trunk of a car or in a bag in the winter for a long time, you will immediately remember the battery.

And you might think, was such a change useful? Ultimately, of course, you decide, based on the operating conditions of the device.

Refinement of the on/off button on the multimeter

It is advisable to further improve the last option for refining the multimeter with the transition to lithium-ion batteries by placing a shutdown button in the power supply circuit of the converter to the battery.

First, the converter itself consumes a small amount of current, even in standby mode when the multimeter is not working.

Secondly, thanks to this switch, you won’t have to click the multimeter itself again to turn it off. Many devices fail prematurely because of this reason.

Some paths are erased ahead of time, others begin to shorten each other. So a button to turn off the entire device at once will be very useful.

Another tip from experienced users of Chinese multimeters is that in order for the switch to serve for a long time and properly, immediately after purchase, disassemble and lubricate the sliding areas of the switch balls.

And on the board it is recommended to coat the tracks with technical Vaseline. Since new devices do not have lubrication, the switch wears out quickly.

You can make a button like an internal one, if you find it free place, and in the external. To do this, you will have to drill only two micro holes for the power wiring.

Flashlight in multimeter

Another innovation for the multimeter - additional option flashlight. Often you have to use the device to look for damage in switchboards and distribution cabinets in basements, or short circuits in wiring in rooms where there is no light.

An ordinary white LED and a button specifically for turning it on are added to the circuit. It is very easy to check how much luminous flux from a given LED is enough. You don't even have to disassemble it to do this.

Place the anode leg of the diode in connector E, and the cathode leg in connector C (the anode leg is longer than the cathode). All this is done in the connectors for the transistor measurement mode on the P-N-P block.

The LED will glow in any position of the switch and will go out only when you turn off the multimeter yourself. To mount all this inside, you need to find the necessary pins on the circuit board and solder two wires to the emitter (connector E) and collector (connector C). A button is soldered into the wire gap and mounted through a hole in the multimeter body.

You secure everything with hot glue and you get a portable flashlight-multimeter.

The multimeter “suddenly” needed wires with alligator clips. I made temporary ones from what came to hand. Two years ago. The wires turned out to be a bit harsh and therefore periodically break off at the soldering points, then cursing, I solder them again and once again tell myself that I need to find the wires, best quality and finally do something more decent.

Soviet wires in measuring probes

And today at the market I saw used probes with suitable wires. Grandfather, over 70 years old, a radio amateur since the 50s of the last century, was selling his property. We talked (he told me how in those years, before making anything out of radio components, it was necessary to first make these radio components - complete subsistence farming). I bought it solely because of the wires. “Made in the USSR” has become a serious brand in our time.

Probes and wires for multimeters

The wires were long, about twenty meters long. I decided to divide it in half. Make some with crocodiles, the second with original probes (if you can straighten their ends - they were too crooked initially). First, I straightened it on an anvil with a small hammer, after preheating the metal with a hairdryer (for better ductility). I was afraid that they would be fragile.

Measuring probes

After preliminary editing, I unsoldered the probes from the wires and continued to give them a more appropriate appearance and condition using electric sandpaper, and then with emery cloth. In the end, everything worked out. I'm thinking of using them for delicate measurements on small components.

I looked closely at the wires, because they were the ones that interested me in the first place. There were 20 copper cores under the protective sheath. Each with a diameter of 0.2 mm. I calculated the cross section: (0.2 x 0.2) x 0.785 = 0.0314 mm/kV This is the cross section of one. Accordingly, the cross-section of 20 pieces (total wire) will be 0.0314 x 20 = 0.628 mm/kV.

(for comparison: copper wire with a diameter of 1 mm has a cross section of 0.768 mm/sq)

Homemade probes and wires

I managed to make two pairs like this: test leads. With crocodile clips and probes.

Checking wire resistance

Since the accuracy of measurements is affected by the resistance of the wires, I could not resist making comparative measurements (although for my amateur radio practice this is not at all significant). The wire with the probe included with the multimeter is 0.5 Ohm.

Wire with probe from production times Soviet Union- 0.4 Ohm. For the sake of objectivity, I note that it is 20 cm shorter.

Chinese and homemade probes for tester

The photo clearly shows the difference between what was and what has become. It took an hour to do everything about everything. The opportunity for this was made possible by the exceptionally successful acquisition of profile wires. But now, having looked under the sheath, we have a real idea of ​​​​what kind of wire we need to look for for the manufacture of measuring wires (multi-core, with a diameter of one core of 0.2 - 0.3 mm and with a total cross-section of all cores of 1 mm, while the wire sheath should be quite thick and at the same time elastic). Author - Babay iz Barnaula.

And probes are always included with the device. Sometimes these are quite high-quality probes that faithfully serve their owner for years. And sometimes, not even a week has passed since the date of purchase of the device, when one of the probes becomes unusable, for example, the wire from the tip or from the plug breaks, or the insulation breaks, cracks, exposing a thin core.

In such a situation, a person certainly comes to the idea of ​​​​buying new probes, and preferably better ones, more reliable, maximally satisfying the needs and requirements, individual requirements depending on his type of occupation, where a multimeter is used regularly or from time to time.

Of course, in such cases, someone decides to repair the probes themselves, and there is a lot of material on the Internet on this topic. You can generally make improved plugs yourself, select the best wires in good, flexible insulation, develop probes to suit your needs, and you’re done. But what if a person simply doesn’t have time to do this, but needs to use a multimeter, needs new probes quickly, and it’s impossible to make a mistake in choosing.

This article is precisely intended to help the consumer somewhat orient himself in the designated topic. What types of probes are there for multimeters? What are their features? Let's look at the nuances, advantages and disadvantages various probes, as well as their purpose depending on the design.

The cheapest, most universal probes are quite simple. They, of course, are not particularly reliable or durable. The wire insulation is made of PVC, the plugs are plastic, as are the tip holders. The electrodes of the tips are made of steel; a thin wire is soldered to them inside the holder. If you accidentally pull the tip, it may come off, so you need to use these probes with caution.

The plugs of different models of simple probes differ in the length of the central electrode, as well as the size of the protruding plastic part of the plug body.

Each device has its own plug mounting depth. For example, the simplest 830 multimeter comes with probes with a short electrode with a diameter of 4 mm, and the multifunctional 266FT comes with an extended banana-type electrode, which also has a diameter of 4 mm.

Is on modern market probes with plug plugs, differing in the shape of the holder, but these are minor variations. If the wire is made of PVC, and the holders are plastic and without flexible sealed inputs, then this is not the best option for probes. PVC insulation cracks easily when bent, especially near the plug.

If the probe wire has good flexibility, is made of a material close in flexibility to silicone, and the inputs of the holders and plugs are sealed and also allow flexibility, these are the most reliable probes. The flexible sealed input of the holder will prevent the wire from being pulled out of it even with an accidental tug.

The surface near the base of the holder, closer to the electrode, should not be slippery so that the probe can be held comfortably and firmly in the fingers when passing measuring work with a multimeter. It is better if the holder has a rubberized surface with small protrusions where the fingers grip it.

Sealed holder entries can also be made of plastic, but such an entry must allow flexibility, that is, have characteristic recesses. It is good if the electrodes and plugs are covered with protective caps, this will avoid puncture injuries, as well as contamination of the plugs, especially if the work is carried out in a dusty environment, as is the case in manufacturing plants.

Branded probes are always more thoughtful, since they are designed taking into account operating experience and the sad consequences of defects. For this reason, high-quality branded probes are often necessarily equipped with sealed flexible inputs of holders and plugs, and the tips and plugs themselves are protected in the form of caps and plugs. The probe wire is flexible enough and does not crack or break due to accidental kinks.

To carry out measurements when working with, on boards or separately, or even for the purpose of piercing the insulation of the wire that needs to be measured, probes with electrodes in the form of sharp needles are intended. Such tips are usually made from of stainless steel or made of brass.

The needles must have protective caps, obviously to prevent accidental wounds, as well as to avoid damage to the needles themselves, so as not to bend, so as not to get into the wrong place, etc.

If your work involves SMD installation, then probes with needle-shaped tips are what you need. With such a needle, you can optionally scrape off the solder mask from the board and take measurements directly on the board. Despite the fact that the needle looks thin, such a probe will certainly withstand a typical 600 volts for a long time, or a current of 10 amperes for a short time.

Especially for measuring the parameters of SMD components, there are also special probes - pliers. With these pliers you will accurately measure the required characteristics and will not miss a component, whether on the board or on the table.

The length of the wire of this probe is not long, and why is there a long wire here? The device is always located nearby when working with SMD.

When special care is required when taking measurements, and it is important not to touch anything unnecessary with the electrode of the probe tip, probes with tips with holes at the ends come to the rescue. With these probes, measurements will be safe for nearby components if we're talking about O printed circuit board, as well as for neighboring conductors, if we are talking about measurements in the process. An accidental short circuit during measurements will definitely not happen.

In some cases, crocodiles are more comfortable view probe tip than sharp electrodes. There are such solutions on the market today.

Probe leads can be short or long.

Crocodiles can have different size, so there are probes to solve any problems related to measurements using a multimeter. One thing is constant here - the crocodile is necessarily equipped with a reliable dielectric shell.

There are crocodiles in the form of connecting tips, as an addition to standard probes. It often happens that the multimeter comes with probes equipped with fastening crocodiles that can be disconnected if desired.

Speaking about connecting tips, one cannot fail to mention kits in which probes, in addition to connecting wires, contain several types of tips. The tips simply screw in like attachments.

This is very convenient when different tips are needed when taking measurements, for example, a tip in the form of a terminal is screwed to ground, and the crocodile is alternately connected to different points of the chain being measured.

Electronics engineers working with lead-out components will especially appreciate probes in the form of hooks and clamps, which are indispensable when taking measurements on, and simply for conveniently holding lead-out electronic components for the purpose of taking measurements.

These hooks are also found in typical probe kits, along with alligators and needles.

We hope that this short article has given the reader some general idea about what kinds of probes for multimeters there are, and what opportunities are offered by their various types to make work easier, as well as the tips that come in sets.

Andrey Povny

Probes are one of the main components of any measuring instrument, including a multimeter - they are included in its kit, regardless of the type and model. Often this device breaks down within a matter of days or months - the wire of one or two contacts breaks, the insulating base cracks, or the tip breaks off. This is due to the fact that most devices include the cheapest products made from low-quality materials.

Many people think about whether it is possible to make probes for a multimeter with their own hands or how to choose high-quality products in a store in order to bypass frequent problems with them. To answer these questions, you first need to familiarize yourself with the varieties of this component of the measuring instrument.

Types of styli by quality

Conditional on price and quality characteristics wires with tips for a multimeter can be divided into two categories:

  1. Budget (amateur, basic);
  2. Branded (professional).

Budget

The cheapest probes, which are included in almost all low-cost multimeters, are equipped with an insulating wire base made of polyvinyl chloride (PVC), and the tip holders and plug elements in them are made of plastic.

A highly thin wire is attached to the steel electrode inside the holding part, which does not guarantee the durability of the product if handled carelessly, since these tips can often come off and the cable simply break. Repair broken ones budget options probes are problematic.

In different models of multimeters, probes may have different mounting depths of the plug element and electrode lengths. The thickness of the electrode in all products is the same - 4 mm, which does not allow the use of such probes for some types of work and measurements.

In addition, do not forget about the disadvantages inherent in PVC insulation material, which are as follows:

  • Probe cables retain their shape when they are wound for a long time - inconvenient to use;
  • such isolation is scary high temperatures and can be easily damaged by the same soldering iron - low heat resistance;
  • low temperatures make the insulation hard, which can lead to deformation and cracks in the cable - fear of frost.

Branded

The multimeter probe can be made of different materials. Reliable and high-quality probes used for professional purposes must meet the following characteristics:

  • The wire for the multimeter must be made of a highly flexible base;
  • The tip holder entry must also be flexible and sealed, and the conductor in it must be firmly seated and resist unintentional jerking;
  • The base of the holding element must have a low slip coefficient so that it is comfortable to hold the probes in your hand during operation. To do this, the holders must be covered additional material, for example, rubber or synthetic rubber.

Interesting to know. The most popular probes among professionals and amateur electricians are made of silicone, as they have all the required characteristics.

Professional probes in most cases are equipped with special protective caps for electrodes and plugs, which prevent dirt from entering the product elements and also protect a person from getting puncture injuries.

Important! Often the holder inputs are made of plastic. It is necessary to ensure that in such products certain recesses are made on the holding element to ensure the required flexibility of the design.

The cable of such products is characterized by high flexibility, strength, resistance to unintentional jerks and does not crack when used in the cold.

Types by purpose

An important part of a multimeter probe is the tip, which mainly determines the purpose of the product.

According to their purpose, probes can be divided into the following most common types:

  • universal options on which various tips are put on;
  • thin probes for SMD mounting;
  • crocodiles;
  • tweezers for checking SMD;
  • thermocouple for a multimeter (probe for measuring temperature);
  • probes in the form of all kinds of clamps, hooks for electronics.

Probes for SMD mounting

Working with SMD elements requires frequent measurements with a multimeter. Only special devices for this purpose can cope with this, which differ very much. fine needle tip made of steel or brass, which can withstand electrical voltages of even 500-600V for a long period of time. They can pierce the insulation of cable products and scrape off the solder mask on the electrical circuit for further measuring activities.

Using a tester or multimeter, you can check the required parameters of small SMD elements on a board or microcircuit when repairing equipment using special pliers that are similar to tweezers. The use of such tweezers guarantees the quality of contact, since during measurement they tightly clamp the component.

A distinctive feature of these products is a rather short cable, but for these purposes another cable is not needed.

Alligator clips

A very common version of the tips of this product are crocodiles in the form of a clamping mechanism. Such crocodiles can have different dimensional parameters, but in all cases they are distinguished by a reliable shell with dielectric properties.

Such tips can act as an auxiliary element to universal devices, which, if necessary, are simply attached to it. Crocodiles are very convenient for holding thin and inconvenient contacts of small elements, which, due to their shape, securely fix them.

Advice. Recommended for professional activity purchase universal wiring with a set of various tips, which will greatly simplify the measurement process and prevent them frequent repairs. In this case, the tips are attachments that simply screw into the holder.

How to make homemade probes

Many people prefer not to buy new products, but to make probes themselves when factory probes fail and cannot be repaired. There are two common options for making them yourself.

Standard pen probes

In order to make such an element for the meter, you will need fountain pens and darts disassembled without rods. The manufacturing process is as follows:

  1. Select components by trying on dart tips for pens;
  2. Insert them into the handles, having previously heated them with an industrial hair dryer or burner;
  3. Place inside the fountain pen heated and soaked in soldering acid a piece of solder;
  4. Place the wires in it and wait for it to cool and fix all components feeler gauge

On a note. For more reliable fixation, the tip of the dart can be additionally fixed with glue.

Insulation piercing probes

For self-creation thinSMD-probes will need the following materials:

  • sewing needles of the required sizes;
  • collet pencils with replaceable leads;
  • Super glue;
  • solder;
  • cable;
  • heat shrink (optional).

CreationSMD-probes are produced in the following way:

  1. Initially, you need to solder the wires to the needles;
  2. Next, insert them into the central part of the pencil collet and glue them so that when pressed they do not disappear inside;
  3. Solder the plugs to the wires;
  4. It is also recommended to apply heat shrink to the product.

On a note. Protective element in homemade products Ordinary pen caps may protrude.

Probes should be selected according to their quality characteristics and purpose - it is better to give preference silicone options. In many cases it is impractical to repair probes; it is easier and more reliable to make probes yourself.

Video

Despite the fact that multimeters are always equipped with probes, in inexpensive models measuring instruments(DT 181, DT 182, DT 832, etc.) their quality leaves much to be desired. The result does not take long to arrive. It happens that not even a month passes before the owner discovers that it is impossible to take measurements with the device, because a wire has broken in one of the plugs or tips. Figure 1 demonstrates typical problem, characteristic of inexpensive Chinese products.

Figure 1. Broken wire – typical fault for Chinese products

Of course, it is not difficult to fix such a malfunction, but this will not solve the problem as a whole, and a new break will not be long in coming. This means it’s time to purchase high-quality and reliable multimeter probes, for example, Mastech products (T3033, T3009, E3029, etc.) or S-Line (ETL-5, ETL-10, ETL-11).


For the sake of fairness, it should be noted that among the products of unknown manufacturers from the Middle Kingdom, you can find quite decent analogues that will be reliable and, at the same time, in no way inferior to the original products. But to do right choice, you need to know what design features you should pay attention to. let's consider Various types test leads to determine their strengths and weaknesses. Let's start with inexpensive products.

A budget option

Measuring probes, in which the wires are PVC insulated, plastic is used as the material for plugs and holders, and the tips themselves are made of steel, as a rule, the most inexpensive. They are included in the kit for budget models of multimeters, such as DT-838 or DT-830B (see Figure 3).


Figure 3. Inexpensive multimeters are equipped with appropriate probes

Usually, test leads are selected different color to correctly connect the device to the circuit being measured.

The standard electrode thickness for such products is 4 mm, and the length varies depending on the model. The shape of the holders may have several variations, but this is insignificant design feature does not affect reliability.

Such products are not the best option, any careless movement may cause the tip to come off. In addition, we should not forget about the disadvantages inherent in PVC insulation, they are as follows:

  • the shape of the wound wires is retained, which leads to inconvenience during work;
  • low heat resistance, insulation is easy to damage with a soldering iron;
  • The wire becomes stiff in the cold and may crack.

It should also be noted that stylus tips with needles with a diameter of 4 mm are not suitable for all jobs. For example, to take measurements from electronic boards where SMD components are located, thin tester probes will be required.

The only advantage budget models- low price. Such products are fully justified when using a multimeter at a non-professional level, that is, for domestic purposes for minor repairs.

Professional equipment

Here are some typical distinctive features, characteristic of a quality instrument:

  1. wires with silicone insulation, they have good flexibility and heat resistance;
  2. the holder and plug must have flexible sealed inputs; thanks to this design, the wires will not break out of them, even if an accidental jerk is allowed;
  3. the holders have a rubberized coating and are equipped with special protrusions for easy grip with your fingers;
  4. the electrode needles (and often the plugs) are equipped with special removable caps. This type of protection has two functions: it prevents contamination of the contact surface and significantly reduces the risk of getting a puncture injury;
  5. anodized or gold-plated electrodes;
  6. small internal resistance of the wire (ideally about 0.04 Ohm).

Products from the following brands meet these requirements: Fluke, Unitrend, Mastech, etc.


Figure 4. Flucke styli complete with crocodile clips

Generally good professional probes collapsible, this allows you to use special attachments for them. It makes sense to talk about them in more detail.

Overview of various attachments

Many manufacturers provide connection to test leads different types attachments, which makes the probes universal and significantly expands the scope of their application (see Figure 5).


Figure 5. Test leads and attachment set

Thanks to this set, you can choose long or short needles, depending on the need, change the thickness of the tip, for example, when you need to make delicate measurements, etc.

To check SMD components, it is convenient to use a special pliers attachment; testing with it is shown in Figure 6.


Figure 6. Checking the SMD resistor

The alligator clip (see Figure 4) is no less useful; it can be used to connect to a device for taking measurements, while during the testing process your hands are freed, which allows you to make other measurements.

Using an attachment that has a spring-loaded hook (Figure 7), you can connect to most attachments on printed circuit boards.


Figure 7. Spring-loaded hook attachment

A nozzle with a terminal adapter (Fig.) allows you to easily connect to a laboratory power supply to control voltage and current.


Figure 8. Terminal adapter

Concluding the topic of professional measuring leads, you should pay attention to one significant drawback of such products - the relatively high price. For example, original Flucke probes with a set of attachments cost about $60.

Homemade probes

It is not at all necessary to buy new test leads if the old ones cannot be repaired. Moreover, it is not difficult to make multimeter probes with your own hands. The result will be somewhat inferior to professional products, but the cost of the products will be disproportionately lower. As for quality and reliability, their level will be no worse than that of their Chinese counterparts.

First of all, you need to purchase high-quality stranded copper wire in silicone insulation. As a last resort, you can use a PVC sheath, but, as mentioned above, such probes will have a lot of disadvantages.

You can use regular fountain pens, felt-tip pens or pencils with replaceable leads as holders. Sewing needles or dart tips from the game Darts are suitable for electrodes.

  1. We disassemble the fountain pen and remove the tip from the dart.
  2. Heat the tip over the burner gas stove and throw some solder into it.
  3. We insert the wire into the handle and solder it to the tip (Figure 9).
  4. Glue the tip to the handle.
  5. We put a heat-shrinkable tube over the output of the wire and heat it until it tightly wraps around the end of the handle and the wire.

Figure 9. All that remains is to glue the tip and put on the heat-shrinkable casing

Second option: we use a pencil with a replaceable lead as a probe; the role of the tip will be played by a sewing needle. The manufacturing principle is almost the same, only the wire is soldered to a needle.

Related video:

Note that pen caps can be used as protective attachments for such probes.