Measurements with a multimeter are made using probes. Not all multimeter probes in kits are of good quality, so it would be preferable to make them yourself. It doesn’t take much time, but then it makes it possible not to be distracted by replacing them. It is also possible to equip the probes with crocodile clips, which will free your hands while taking measurements. Sometimes it is useful to have both measuring collapsible thin probes and a model with alligator clips; each of them will be indispensable in certain situations.
Alligator clips are very convenient to use if you need to fix a conductor for accurate measurements with a multimeter. To carry out the work you will need the following tools and components:
Wires use stranded copper because copper has good conductivity and flexibility. Silicone shells are soft, flexible, and will not break or crack over time. You can find an option specifically designed for black and red multimeters.
To make homemade probes, you need to connect the wires with plugs and clamps. If you know how to solder and have everyone necessary tools the procedure will take no more than half an hour.
It is advisable to select the same color for the plug, wire and clamp, so that one probe is, for example, completely red, and the second completely black. In this case, the multimeter will be convenient to use and it will be easy to observe polarity when taking measurements.
First, you need to insert the wires into “bananas”, through which they will be connected to the multimeter. The connection with the plug is not particularly difficult.
A bolt is unscrewed from the banana, after which a wire can be inserted inside, the end of which has been stripped in advance. Then you need to tighten the bolt, thereby securely fixing the wire inside. The same operation is performed with the other wire. At this point, the “bananas” can be considered connected.
On at this stage strip and tin the free ends of the wires that will go to the alligator clips. Next, take a crocodile clip for a wire that matches the color. The insulation is removed from it and the bolt is unscrewed.
Clamping the wire with bolts is not the most reliable solution for multimeter probes. It will be better to solder it in this place, having first made a small soldering pad out of tin. The second “crocodile” also joins.
Now you can start soldering the crocodile. To do this, a wire is inserted inside, bringing the tinned end to the prepared area.
The wire must first be covered with crocodile insulation so that it can then be pulled over the connection.
Solder is taken and the wire is soldered to the crocodile. The soldering must be strong so that the wire does not fly off at the slightest tension. When the wire is soldered, you need to clamp it with the lower edges of the crocodile body; this can be done using pliers.
After this, strong clamps are formed, which will guarantee the long-term serviceability of the homemade probe. Next, the insulation is put on the crocodile. This is necessary for its reliable and safe operation, as well as for its aesthetic appearance.
You can also make thin probes for a multimeter. The cheapest and easiest option is to make them from the body of handles. Everything here is very similar, only instead of clamps you will need the following parts:
As a tip, either buy special thin probes for a dt multimeter, or use thin sewing or medical needles. It is better to use special probe needles, purchasing them on the radio market or in an online store.
Everything else you need is the same as in the previous version of making probes for a multimeter. The plugs are connected in the same way as described above, and securing the tips of future probes has several features.
To begin with, one hole is made in the top caps of the pens. This is necessary for the wire to go inside. It is desirable that their diameter matches the diameter of the wire. Next, the lower part of the handle is disassembled and a needle is inserted into it.
The needle must be soldered to a wire that is previously inserted into the cap. The solder should not be made too thick, but it must be soldered securely. The soldering process was also described above.
When everything is ready, silicone is poured into the lower part of the handle and until it hardens, the needle sticks out according to the level. She should not be disturbed for several hours.
You can do it this way. First, stick the needles out 4-5 cm, then put on the cap. Thus, the tips for the probes will independently take the desired position. When the silicone has hardened, the structure is strong and comfortable.
To check the device for functionality, you need to measure the resistance of the probes. To do this, you need to connect the multimeter to the network and set the switch to measure resistance.
If the multimeter does not have automatic range adjustment, you need to switch to measuring the lowest limit.
Insert the leads of the probes into the sockets of the device, and then connect the probes to each other. The resistance figure should be 0, or as close to zero as possible. If the multimeter is automatic, then a couple of seconds after the circuit is closed, the device itself will set to 0.
If you know the sequence of the process, then all the work will not be difficult. You need to have minimal soldering skills, and then everything will be done quickly, and the device will last for many years.
Probes are an integral part of all multimeters, which comes complete with measuring instrument regardless of its model. Good probes For many years they have been faithfully performing their task. But it also happens that a few days after purchasing a multimeter, one or even both contacts fail due to a broken wire, broken tip or cracked insulation. To protect yourself from such a nuisance, you need to purchase high-quality and reliable multimeter probes, with good wires and durable tips. Many people prefer to make them themselves. In this material we will talk about the varieties and features of these elements, and also figure out how to make homemade probes for a multimeter.
These products are the simplest and cheapest. They are included with most inexpensive multimeter models. The cables of these elements are equipped with PVC insulation, and the plugs and lug holders are made of plastic. Attached to a steel electrode from inside the holder thin wire. Such tips can easily come off if not handled carefully. It is clear that there is no need to talk about durability and high reliability here.
Different models of universal contacts have unequal lengths of the central electrode of the plug and the protruding part of its body. They also differ in the mounting depth of the plug.
The multimeter may have a probe made of various materials. High-quality and reliable contacts can be distinguished by the following characteristics:
The video shows an example of such products:
Silicone probes have all of the above properties. These parameters are responsible for the high popularity of such products.
Often the holder inputs are made of plastic, but in this case they must have special recesses, otherwise the element will not have the required flexibility. On almost all branded models, plugs and electrodes are equipped with caps that protect the elements from contamination and minimize the possibility of puncture injuries.
These products were developed taking into account the experience of using earlier models, and therefore are distinguished by their thoughtfulness and ease of use. The wire of such contacts has sufficiently high strength and flexibility, is resistant to accidental jerks and does not crack when bent.
When working with SMD elements, it is periodically necessary to carry out measurements, which can only be done using devices connected to the tester. thin probes. These products are equipped with sharp brass or stainless steel needle-shaped tips. They are necessarily protected with caps, which minimize the risk of electrode fracture or accidental injury to the technician.
For SMD installation specialists, such elements are most convenient to use. Sharp probes can not only pierce the wire insulation, but also scrape off the desired area solder mask on the surface of the board with further measurement work. Although the thickness of this needle is very small, the element can easily withstand a voltage of 600 V for a long time.
For measuring work when installing SMD components, multimeter probes are also provided. They allow you to measure the required parameters of a part both on the desktop and directly on the board.
During the measurement, the component is clamped with pliers, which guarantees the quality of the contact. These products have a fairly short cable, but a long one is not needed to work with SMD.
If the measurement process requires maximum care to prevent the electrode from touching other parts, then it is best to use probes with holes at the ends.
With their help you can make measurements as printed circuit boards, and during electrical installation work without fear of accidentally causing a short circuit.
This tip option is also available on modern market and is in great demand. In some cases, it turns out to be preferable to sharp electrodes. The size of the “crocodile” may vary, but in any case it must have a reliable shell made of dielectric material.
Connecting tips can be made in the form of “crocodiles”, serving as additional element For standard probe. Often, the kit for the multimeter includes tips in the form of clip-on “crocodiles”, which, if necessary, can be either detached or attached.
It is also necessary to mention the kits, which include several different tips. When starting work, the master himself selects the one he needs and screws it in like an attachment. This feature allows in some cases to significantly simplify the measurement process. So, for example, a crocodile can be connected in turn to different sections of the electrical circuit being tested, while the other tip is attached to ground as a terminal.
Technicians who work with terminal components prefer terminals designed in the form of clips and hooks. With the help of such elements it is convenient to produce measuring work on printed circuit boards, and also hold lead components in place during measurements. These tips, as well as needles and crocodiles, can be included in the delivery package.
As we said above, many people prefer not to buy new ones when factory probes break down, but to make them themselves. Let's consider two popular options for making homemade products.
To make them you will need dismountable fountain pens (without refills) and dart tips for darts.
The operating procedure is as follows:
For additional fixation, the dart tip can be glued.
The entire device is clearly shown in the video:
Now let's figure out how to make thin probes for a multimeter with your own hands. To do this, we will need collet pencils that use interchangeable leads, and sewing needles of suitable thickness.
The production of thin probes is carried out as follows:
It is advisable to apply colored heat shrink to the resulting products. When working with a hair dryer, you need to be careful, as the flow of hot air can cause deformation of the plastic.
Pen and pencil caps can be used as protective elements.
The video shows an example of making needle probes for checking small parts:
From this article you learned what tester probes are needed for, what types of these products there are and what are the features of their use. Well, for those who like to assemble on their own electrical devices and products, you will probably be interested in information on how to make multimeter probes with your own hands.
Price: $2,3
The probes that come with inexpensive testers (multimeters) are often not best quality. And sometimes they deteriorate: sometimes the wire breaks, sometimes you accidentally burn it with a soldering iron. And so, we already have to throw away cheap disposable probes and look for a replacement for them.
These probes looked very solid in the photos in the store. Colored plastic, caps and plugs, good length (107 cm). The price is absolutely ridiculous.
And now I’m already printing out the parcel.
The first impression is great. Everything is very neat and beautiful. The wire is soft, silicone. The probes are simply pleasant to hold in your hands. They immediately registered on my work multimeter.
I've been using them for almost a year now. During this time, I realized that their price is quite justified.
Yes, they are beautiful, the handles are molded from two-color plastic.
There are grooves on the contacts, which is very convenient for measurements. The total resistance of the two probes is 0.9 Ohm. The caps and plugs got lost very quickly, but I don’t need them. Their main drawback is the banana connectors that are inserted into the sockets of the multimeter. They are beautifully made, filled with plastic, but they constantly lose contact.
I cut the protective plastic so that they would go deeper, but that didn't help much. The contact also fell off from time to time. I endured as long as I could. But this is very inconvenient, especially when you call many different circuits, there is no short circuit everywhere, and then you connect two probes and there is no contact there either. You understand that all the work needs to start all over again. And the question arises: “Do I need such probes if they are not trusted and constantly let me down and complicate my life?” I felt sorry for throwing them away; I was already used to them, so I decided to replace the unreliable link.
The connectors were mercilessly cut off and thrown away, and to replace them I picked up gold-plated “bananas” with a rotating slip ring. This is convenient because the connectors will not “break” the multimeter sockets when rotating and the contact should be more reliable. New connectors are inserted into the tester sockets very tightly and are fixed securely. They also have holes where you can insert the same “banana”, sometimes this can be very useful. Why did I choose these "bananas"? I just didn’t find specialized connectors for testers, but I had already used these “bananas” and I really liked them for their “tightness” in the socket and ease of rotation while maintaining excellent contact. And besides, they were bought from me a long time ago and are lying idle
In order to solder new connectors to the probes, I strip the insulation.
And here is another disappointment. Although the wire itself seems thick and solid, the twisted copper core in it is thin...
Now it’s clear why there is such resistance, the copper there is a cat crying... The quality of the wire is no good, it wouldn’t be a bad idea to change it. But the probe handles with contacts themselves are cast and non-removable. Changing the wire in such probes is the same as simply throwing them away. Therefore, I decide to leave the wire as is for now, and at my leisure, look for blanks for probes and a good wire and make new probes myself.
In the meantime, we attach the new “golden” connectors to the wire. They are connected without soldering. Simply insert into the connector tube and secure with a screw.
To prevent the wire from breaking at the base of the connector, I reinforced it with heat shrink.
Then another heat shrink, shorter.
I run the clamping screw so that it can tighten easily.
And on top is the plastic part of the connector.
Here, in fact, is the result.
The first tests showed that the probes (which were far from ideal initially) began to behave noticeably better. The contact in the multimeter sockets is now quite reliable (in several months they have never popped out and the contact has never been lost), the probes themselves are movable and can be easily turned. Additional functionality has appeared in the form of additional contact holes for bananas.
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.
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 wires of better quality and, in the end, make 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: 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 these two pairs 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.
