Probes are one of the main components of any measuring instrument, including a multimeter - are included in its kit, regardless of the type and model. Often this device breaks down after just a few 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.
Conditional on price and quality characteristics wires with tips for a multimeter can be divided into two categories:
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:
The multimeter probe can be made of different materials. Reliable and highly quality probes that are used for professional purposes must meet the following characteristics:
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.
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:
Working with SMD elements requires frequent measurements with a multimeter. Only special devices for this purpose can cope with this, which differ very 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.
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.
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.
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:
On a note. For more reliable fixation, the tip of the dart can be additionally fixed with glue.
For self-creation thinSMD-probes will need the following materials:
CreationSMD-probes are produced in the following way:
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.
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 from 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 originally). 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: a copper wire with a diameter of 1 mm has a cross-section of 0.768 mm/sq.m.)
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 the 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.
Quite often, such a nuisance occurs as a wire (cable) breaking near the plug. This happens especially often with wires that are subject to constant vibrations and movements. For example, with headphones chargers, multimeter probes and the like. We notice the gap, as a rule, only after the thing we are using stops working. And it’s actually quite difficult to notice this. If only by chance we see... The break does not occur immediately, with the exception, of course, of a rough mechanical impact. The cable braid is usually damaged first.
Hi all!
Now on sale various testers, but in most cases the probes for them are of low quality.
There was a case where in the cold the wires of the probes broke like matches. So I decided to make the missing probes myself.
Trying on a dart tip. It needs to fit the size of the pen tip. If it doesn't fit, you'll have to cut off the thread on the handle. If this does not help, then you will have to find other pens.
Take the tip of the dart and heat it gas burner. After sufficient heating, take a piece of solder dipped in soldering acid and throw it inside. We lower the wire there and wait for the solder to cool.
We assemble the dipstick. It is better to glue the tip.
Second set. Probes with needles for puncturing insulation. We take pencils with replaceable leads and take them apart.
We take needles and try them on instead of leads.
Solder the wires to the needles.
Insert the needle and wire into the pencil from behind. It may not work the first time; you need to hit the center of the pencil collet. The needles must be glued into the collet, otherwise they will go inward when pressed.
In general, everything is ready, all that remains is to solder the plugs to the wires and cover the probes with colored heat shrink. Be careful with the hairdryer! The plastic of office supplies may become deformed.
Pen caps came in handy too.
Addition. While disassembling the computer power supply, I discovered a connector whose terminals fit very well on all probes, including Chinese and Soviet ones.
Therefore, I decided to also make crocodile attachments. We remove the terminals; they are held in the block by latches. Press the latch with an awl and remove the terminal. We cut off the shank at the terminal and bend the latch inward.
We take the alligator clip, insert the terminal, and solder it.
The crocodile is ready.
Thanks to all. In conclusion, I will say that I bought wires with frost-resistant insulation with a cross section of 0.75 mm?.
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 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
