How to check battery terminals with a multimeter
Dirty, corroded or loose terminals will lead to starting problems or no starting, and is one of the main reasons people think they have a “dead battery”. Sometimes such problems are difficult to detect with a simple visual inspection..
Here you will use a voltmeter (or multimeter set to voltage) to check the battery terminals for voltage drops so you can understand the status of your battery connections..
Turn off the ignition system first. Do this by temporarily disconnecting the ignition coil or removing the fuse or fuel pump relay (if necessary, look for your vehicle manual or your vehicle repair manual to find the coil or fuse). This will prevent your engine from starting..
With the red positive wire, touch the positive pole of the battery and hold. With the black wire (minus) of your meter, touch the terminal of the minus wire that is put on the battery. Ask an assistant to crank the engine. If your meter reads more than 0.5 volts, you need to clean or check the physical condition of the terminal and terminals.
Now check the other battery terminal. This time, however, with the black test lead of your meter, touch the negative pole of the battery. Now touch your meter’s red probe to the cable terminal connecting the same battery lead. Have your assistant start the engine and check the voltage reading on your meter. If it exceeds 0.5 volts, check the battery terminal for damage or clean it.
Software ways to check the battery on Android
Android in encrypted form in the system contains a log of battery information. This information can be obtained using special utilities. For example, the Battery app, “Battery Care” and other analogs.
You can find various magic codes on the Internet, but they do not work in new versions of Android. In addition to the number of charge and discharge cycles, these utilities demonstrate the operating temperature of the battery. You should pay attention to this parameter if the battery gets very hot..
How to check the battery level while charging?
Many of the newest chargers are equipped with additional indicators that allow you to accurately determine the state of charge of the battery during the course of the charging process itself. Some of the more advanced devices have a display that shows the current voltage value that the battery has managed to reach at the moment..
So, how to know that the battery is charged and it’s time to complete the process?
If the charger is equipped with an indicator, then when the battery is fully charged, it usually lights up green. If there is a display on the charger, you can see the value of the battery voltage: its value in the range from 12.6 V to 12.9 V indicates that the battery capacity is fully restored. In addition, you can always use a multimeter, measuring the voltage at the battery terminals with it, if you use the simplest charger that is not equipped with additional functionality for charging..
Some chargers with a digital display have a special button to check the battery level. Having disconnected the charger from the mains, hold this button down and read the readings from the scoreboard.
As you can see, there are many options to determine if the car battery is charged. Which one to use, decide for yourself. In many respects, this will be determined by the selected charger, with the help of which the battery is charged..
How to find out the real indicator of capacity
In practice, the actual and declared by the manufacturer values of the battery capacity of the phone may differ several times. To get information about the actual indicator, it is necessary to conduct special testing, resorting to the use of third-party software.
Types of multimeters
Asking whether it is possible to measure the battery capacity of a car, smartphone, laptop or any other household appliances with a multimeter, it is necessary to consider the types of devices presented.
There are analog and digital multimeters. In the first case, the measurement result is shown by an arrow on a special scale. This is one of the cheapest types of devices. However, for those who have never used such devices, it is better to give preference to digital varieties. Also, analog multimeters have a small measurement error..
Digital multimeters display the measurement result on the display. This distinguishes them from the previous group of devices. Information on the screen is highly accurate and understandable for any user.
How to check the battery capacity of a screwdriver with a multimeter
The main property of the battery is capacity. This value shows the accumulated energy, that is, the current strength for 1 hour. Measured in A / h.
How to check the battery capacity with a multimeter?
- Disconnect the battery from the screwdriver.
- Charge the battery 100%.
- Using a multimeter, a resistor and a light bulb, measure the time it takes for the lamp to go out, the voltage at the output of the battery.
- Calculate the capacity of the device by the formula /
- Compare the results obtained with those indicated in the instruction manual of the screwdriver.
Capacity calculation formula:
E = M / Nt,
M – light bulb power,
N – screwdriver voltage,
t – battery discharge time.
Let’s say the battery voltage reaches 18V. With an incandescent lamp power of 10 watts, the discharge time of the battery should reach at least 2.3 hours.
If the connected light goes out after 30 minutes, then the calculated capacity of the battery will be:
10 W / 18 V 0.5 h = 0.28 Ah
This value is significantly lower than the values, for example, of a nickel-cadmium screwdriver battery of 1.3 Ah..
Determination of the capacity of power supplies
If you are interested in how to measure the battery capacity with a multimeter, first of all it is worth understanding the concept itself. Capacity is the product of the constant current of the battery discharge by the discharge time in hours. It is measured in milliampere-hours and displays the operating time of the battery at the maximum load of the device connected to it.
Thus, we can conclude that it cannot be checked directly with a multimeter. Measuring the capacity is possible only when making measurements with a multimeter and a stopwatch at a discharge rate of up to 1 volt and below, supplying a load of 0.1-0.15 amperes to the battery. The load value is multiplied by time and the required value is obtained. Any terminating resistor can be used as a discharge device..
With this method, you can both check the phone battery with a multimeter for a discrepancy between the declared capacity and the true one, and determine the approximate charge-discharge cycle time. The first is very useful if you purchased a device from China – the batteries of their smartphones are often labeled with deliberately false, inflated information about the capacity..
How to check if the battery capacity has decreased on Android?
Lithium batteries degrade with each discharge cycle – this is a regular aging process. But there are additional factors that exacerbate wear and tear. Have you left your phone in the sun or talked on it for a long time in the cold? During the trip, it was discharged, but there was no outlet nearby? All this increases the likelihood of battery swelling..
Charge loss rate
The easiest way to check if an Android battery has lost its capacity is to track how quickly it discharges. If it “melts” from 100% to 0% without much load and software failures in a few hours, then the battery is most likely dead.
Bottom line: no smartphone in the world in good condition loses more than 2% per hour in standby mode. Most of them are discharged by a maximum of 6% over a whole night..
How to check the battery of a screwdriver with a multimeter?
During intensive use of the screwdriver, there is a possibility of its breakage. And one of the most vulnerable parts is the battery. Consider how to check the battery of a screwdriver for performance by different methods.
Nickel cadmium battery
The most common type of battery. They charge quickly enough and have a good volume. They are distinguished by their durability and resistance to external influences. The average number of charge / discharge cycles can reach 3500. When using accelerated chargers, the battery does not wear out faster and can last for a long time. Separately, it is worth noting the cheapness of such batteries and the ability to operate at temperatures below zero..
But there are also disadvantages, the main one of which is the so-called “memory effect”. Batteries are quite toxic in the event of a malfunction and have a high self-discharge rate. Due to toxicity, manufacturers are now trying to rapidly reduce the percentage of such devices..
To prolong the life of such a battery, it is recommended to completely discharge it before recharging..
Li-ion battery
A much more expensive analogue, which, however, has a number of undeniable advantages. Such batteries are used in leading models of screwdrivers from well-known brands..
These batteries have a large capacity and a much lower percentage of charge loss due to self-discharge. However, such batteries are strictly not recommended to be overheated and left completely discharged for a long time. This can lead to degradation of the crystals and damage to the battery. If overheated, there is a risk of explosion of such a device..
Like the first type, the lithium-ion battery is capable of functioning in cold weather..
How to check
General recommendations before testing the battery
Immediately before checking the battery, it is necessary to clearly determine what type of battery the battery belongs to. Depending on this type, and the approach may be different. For example, the most common nickel-cadmium batteries are highly sensitive to operating conditions. Infrequent or irregular full recharges will significantly reduce the battery’s capacity and the battery will not fully utilize its resources. We will consider the types of batteries in more detail below..
It is also recommended to fully charge the battery before checking. This will make it possible to draw more accurate conclusions about the performance of the device. It has been proven that the most accurate readings are taken under load. And the full charge is a very suitable type of load.
Before testing, it is necessary to minimize the influence of the “memory effect” on the device. Since this effect appears with batteries in case of improper use, in order to eliminate it, it is necessary to use the battery several times in accordance with all the rules..
It is enough to carry out the charge / discharge cycles 3 times to significantly reduce the effect of the effect. For an accelerated discharge, it is best to use an incandescent lamp, which, together with a multimeter, will need to be connected to the battery..
If everything is done correctly, then after a few full cycles the battery will be able to restore its capacity and can again be used in a screwdriver. If the operation did not help, then the problem was different..
Charger
The malfunction may lie not only in the battery, but also in the charger itself. Therefore, you first need to check the charger for the screwdriver with a multimeter.
On it, the mode of measuring direct current is switched on and, using probes, it is connected to the charger. The value of the current on the meter should be as close as possible to what is indicated on the case. If this is not the case, then it is better to replace the device with a new one..
How do you test your Screw Driver Tester.
Battery can voltage
After the first stage of verification, it will become clear whether the device is working properly or not. If the testing indicated a mismatch in the parameters, then it is logical to proceed with the repair, accompanied by the replacement of faulty cans..
You need to open the battery case and identify the malfunction. For this, a multimeter is also used, which is connected to each element separately. The voltage of each jar must be at least 1.2 V. All discrepancies indicate a breakdown of the element. Defective cans must be removed from the common circuit and replaced with new ones..
If such a check does not reveal a breakdown, then you need to resort to stress testing again. And here the level of resistance is of fundamental importance, which is directly related to voltage and current strength. Each element is tested separately and resistances are calculated as well. In the event of a malfunction, this indicator will clearly deviate from the norm and quickly identify a broken element..
Inspection tools
To check the battery, you will need to have a voltmeter, ammeter, connecting wires and devices for capturing contacts: clips such as crocodiles or clamps. Sometimes the design of the battery pack contacts does not allow connecting instruments without disassembling the case. It is very possible that you will have to engage in soldering. Here is a list of the essentials:
- Charger (original or compatible);
- Multimeter (or better two);
- Resistance 4.7 … 10 Ohm for a power of 5 W or more;
- Automotive lamps 12 V, several pieces;
- Hook-up wires, cross-section 0.5 mm.kv, 1.5-2 m;
- Screwdriver;
- Sharp knife;
- Scotch;
- Soldering iron with solder and flux.
Instead of a native charger, a laboratory power supply would be very suitable, with a voltmeter and ammeter for a current of several amperes and a voltage of several volts above the rating of the battery under test. For example, an indoor switchgear from a car, if it has good built-in instruments for measuring current and voltage.
To check the battery of a screwdriver, a multimeter is most often used, it is also suitable for measuring the capacity of the battery..
In addition to everything else, you need to prepare a comfortable workplace with good lighting, remove flammable liquids and objects away.
General repair recommendations
How to restore a screwdriver battery? You need to have a basic understanding of electrical engineering. The battery circuit is idle. Ordinary serial circuit (plus connects to minus).
When repairing Ni-Kd, the following recommendations should be taken into account:
- They have a memory effect. The classic scheme for commissioning such batteries is 3 full charges and 3 discharges to zero. The new element must go through the same buildup.
- A similar item. So that it does not get knocked out of the chain and does not break the battery at all, the new element must fully correspond to the previous rating.
how to check battery and alternator without tools
The lithium battery of a screwdriver can be repaired at home if you consider the following:
- They cannot be soldered. Intolerance to high temperatures will lead to a non-repairable condition. To do this, you need to use contact welding (it heats the electrode for a short time without harming the battery). If there is no access to the COP, soldering with a very powerful soldering iron from 100 watts is allowed. Movement must be fast and accurate.
- Identical models. Now there are several major manufacturers of lithium batteries, which are used in popular foreign models of screwdrivers, such as Hitachi, Makita and domestic ones: Interskol, Zubr.
Battery design and types of cans
The battery for screwdrivers is made as a small block, docked with the tool from the back, usually on the bottom of the handle. This is done for an optimal center of gravity and comfortable grip. The block can be easily removed and fixed in its socket. Everything is done for convenient and fast work.
The unit itself is a plastic case with batteries inside. Since the existing chemical current sources do not provide the typical power supply voltage of the screwdriver (12-18 V), they are recruited into a serial battery. The leads of the elements are connected by a metal flat bus, which is welded to them by contact welding. This method heats up the elements the least during assembly..
Thus, the battery is not repairable. In developed countries, they are disposed of without repair. Elements, or as they are simply called, “banks”, are also made non-separable, moreover, sometimes they contain harmful substances. The elements are cylindrical or rectangular in shape..
Battery types
For cylindrical elements, usually Ni-Cd or Ni-MH, the electrodes together with the active mass and the separator are rolled up, while for rectangular ones they are collected in a package, or sometimes they are also made in a roll. The goal of any of the methods: to maximize the area of the electrodes, which gives the maximum current draw with a minimum of heating. This provides a high power density of the cell..
Lithium-ion cells are produced in both cylindrical and flat cases, and lithium-polymer with ribbon or wire leads – in flat.
In general, the design is similar to oil capacitors, only there the electrodes are called plates, and they are separated by a non-conductive dielectric – oil. In the case of batteries, on the contrary, the filler conducts current, it is an electrolyte solution.
Battery performance is associated with electrode corrosion and other irreversible chemical processes. Gradually, it loses its effectiveness and becomes unusable. Incorrect charge-discharge mode accelerates these events.
REMEMBER: Nickel-cadmium batteries must be discharged to their minimum voltage and only then charged. And lithium-ion – on the contrary, recharge more often. This extends their service life..
Corrosion disturbs the shape of the electrodes, leads to ruptures and punctures of the separator and further closure of the cathode and anode. This increases self-discharge. The formation of poorly soluble compounds in large quantities leads to an irreversible increase in internal resistance. Such compounds are obtained in the course of side chemical reactions, which are inevitable and limit the service life..
Improved battery screwdriver recovery method
What was suggested:
- before carrying out any manipulations with the supply of a pulse current and charging, the author of the method selected elements from the assembly, the voltage at which was zero;
- a hole was made in their body with a micro drill and a thin drill;
- a cubic centimeter of distilled water was pumped into the hole of each element;
- after that the batteries were allowed to stand for some time and their voltage was measured. Elements with zero voltage “cheered up” with impulse current;
- then the cells were charged;
- after that, it is recommended to leave them for a few days, and then check the voltage again;
- if the elements are alive, then the holes are sealed with sealant or sealed. The battery is collected, charged and the screwdriver is ready for use;
- if the voltage is again zero, then another “cube” of distilled water is added, and the process is repeated until successful completion.
You might be interested in an article on how to check the battery capacity of your phone..
Action guide: how to check the battery of a screwdriver
Battery pack malfunctions are the most common problem for owners of hand-held power tools. Mechanics break down less often. As a result of haste and negligence when using the tool, the charging and discharging regime of the batteries is disrupted. The result is a two to threefold reduction in battery life. I have to buy a new one. But before buying, it is worth checking the condition of the battery to make sure that the problem is really in it..
How is the restoration and repair of Ni─Cd batteries performed
The performance of Ni-Cd batteries (like any other) deteriorates over time and after a while they can come to a state of “zero” discharge. At the same time, charging cannot affect this state in any way. They simply refuse to accept the charge. At the same time, the batteries still have enough resources for further operation. Therefore, over time, there were some ways to restore them. Whether to buy a new nickel-cadmium battery or restore an old one is up to you. We just tried to summarize the data that we managed to find on the Internet about the restoration and repair of Ni─Cd batteries.
How to check the lithium battery of a screwdriver
Inspection tools
The multimeter is an indispensable tool that is often used during battery testing
Each person who is going to check the performance of the battery should familiarize himself with the list of required documents. To carry out the work, you will need the following:
- voltmeter with a constant voltage of 15 V;
- tester;
- multimeter;
- ammeter.
In some cases, you may need the following tools:
- soldering iron;
- knife;
- Straight or Phillips screwdriver
- pliers.
It is better to prepare all this in advance, so that everything you need is at hand.
Lithium
Lithium drives are considered the highest quality and most durable
Another common type of battery is lithium ion. Their voltage is 3.7 V. These storage elements have a huge number of advantages:
- complete absence of self-discharge;
- large capacity;
- many charge and discharge cycles;
- compactness and light weight;
- no “memory effect”.
Lithium batteries have a serious drawback – high cost. It is almost three times higher than the price of other types of drives..
Checking under load
The car headlight bulb is used to load the battery
If a person needs to figure out how quickly the drive will discharge, it will have to be checked under maximum load. Its power is equal to half of the current, which is given by the battery. Most often, this value is about 30-40 watts. Therefore, to create a load, you can use a regular lamp from the headlights of the car..
When taking measurements, the battery is connected to the load source using an ammeter. To measure the readings, you must use a voltmeter. The battery turns on for 3-4 minutes. During its operation, the voltage should not fall below 12.4 V.
Important! If the reading fluctuates, the battery is partially damaged and will drain quickly.
How to check the battery of a screwdriver with a multimeter
Many people do not know how to check a screwdriver battery. There are several ways to do this..
Screwdriver battery design and types of “cans”
Regardless of the tool model, all batteries in them have the same design. Inside there are elements connected in series – batteries with “banks”. The resulting battery voltage is created by summing the voltages from all of these components..
The rechargeable design has four pins that are easy to see on the device:
- Two power, used when discharging and charging the battery.
- One controller, which is connected to the installed thermal sensor. Used to protect the charging from overheating.
- The fourth contact is service. Needed to check the charges in the installed batteries.
Important! In some battery containers, the service contacts are responsible for voltage equalization..
Checking by resistance value
You can check the battery performance by comparing the internal resistance of the “cans”. To find out this value, you will have to divide the voltage by the current and subtract the load resistance.
A 10 ohm resistor is recommended for the load. If the received value is less than 1 ohm, then the battery is functioning normally..
Checking the Drive Batteries
The breakdown of the battery “can” often leads to deterioration of the battery
If, during the preliminary checks, faulty components were identified, you will have to disassemble the battery and remove all the main batteries. Perhaps one of them is out of order and it is because of this that the battery performance deteriorated..
First, you need to carefully examine the connections. Quite often, they are damaged, which leads to an overall decrease in battery performance. If everything is visually in order, you need to ring the “banks”. The voltage of these elements must not fall below 1.2 V.
A Few Tips Before Checking Your Battery
Before proceeding with the battery test, you need to determine its type in advance. The fact is that how the check will be carried out largely depends on him..
Also, before checking the battery with the tester, it must be fully charged. This will help you check the drive is working properly. It has been repeatedly proven that the most accurate indicators can only be found under load..
Before checking, it is imperative to get rid of the “memory effect” that appears over time with most batteries. To remove it, you must fully charge and discharge the battery at least three times..