When is the average salary used to calculate alimony? How to make a load plug for a battery with your own hands? When you can save money Make your own battery fork

Today we will look at what a battery load fork is, what it is intended for and how to use a load fork.

Due to the great popularity of the article “How to test a battery,” I decided to expand on this topic and increase your knowledge in the field of operation and maintenance of batteries. And we'll start by studying the load plug for batteries.

The load plug is designed to determine the state of charge (discharge) of the battery and is a good assistant for determining the health of the battery when testing it.

Also, the built-in voltmeter of the load plug can be used when diagnosing elements of the vehicle’s on-board network.

In general, the load plug is a voltmeter, parallel to which a load made in the form of a spiral is connected. The load can be disconnected if necessary, and the plug can be used as a voltmeter.

The electrical circuit of the simplest load fork is shown in the following figure.

Types and types of load forks for batteries.

There are a large number of load forks. But they differ only in the voltage measurement range with a voltmeter and the load size.

You can also divide the load forks according to the type of battery being tested. That is, there are plugs for acid batteries and for alkaline batteries. Again, they differ only in the load they contain.

You can see one of the striking examples of a load plug for alkaline batteries in the figure. This is a plug with interchangeable loads from 1 to 12 amps.

The reason I say this plug is used to test alkaline batteries is because the maximum load included with the plug produces a load current of 12 amps. We’ll look at how to choose a fork based on the size of its load below.

Unfortunately, I have not determined the type of this load fork due to the lack of markings on the body.

The next version of the load fork is designed for testing individual battery cells, if the battery design allows it.

For these purposes, the NV-B fork is used. It has a voltmeter with a maximum voltage measurement range of 3-0-3 volts. The current load created by this plug is 100 amperes.

This plug can be used to test 1.2 volt alkaline batteries and to test 2 volt acid batteries.

To test 12-volt car batteries, you need a plug with a voltage measurement range of at least 15 volts.

For example, the E107 UHL4 plug. It has a voltmeter with a scale of up to 20 volts, a load resistance of 0.1 Ohm, that is, it is designed for a load of 100 amperes.

The most modern version of the load fork is the HB-03 fork. It has an electronic voltmeter with a liquid crystal indicator. It contains two 100 ampere loads, with the ability to connect them separately to the plug.

When connecting one load (total current load - 100 amperes), batteries with a capacity of 15 to 100 Ah are tested. When connecting two loads (total current load 200 amperes), batteries with a capacity of 100 to 240 Ah are tested.

The diagram of the NV-03 load fork is shown in the figure.

Also, the NV-03 load fork has several additional functions: automatic determination of the battery charge level; recording the values ​​of measured voltages into memory, etc.

Attention! The NV-03 plug has the ability to calibrate a voltmeter and a range of temporary voltage measurements under load. Therefore, before use, it is advisable to make sure that the plug is calibrated.

Selecting a load plug depending on the type of battery.

So, we are faced with the question: “How to choose a load fork?”

1. Determining the range of measured voltages using a load plug voltmeter.

As I described earlier, load forks are available in different voltage measurement ranges.

The most common forks with the range:

2-0-2 volts (for alkaline batteries with a voltage of 1.2 V)

3-0-3 volts (for alkaline batteries with a voltage of 1.2 V and acid batteries with a voltage of 2 V)

0-15 volts (for 12 V acid and alkaline batteries)

0-20 volts (for 12 V acid and alkaline batteries)

0-30 volts (for 24 V acid and alkaline batteries)

Here only one condition must be observed: the measured voltage should not exceed the maximum value of the load plug voltmeter.

2. Selection of current load.

When testing a battery using a load fork, you must select the correct current load value.

When testing a battery under load, we physically connect the plug load to the battery, creating a discharge current in the resulting circuit.

For a better test of the battery, this current should have a maximum value, but not exceed the permissible value of the discharge current recommended by the manufacturer of this battery.

Of course, not all manufacturers provide the value of the maximum permissible discharge current for their batteries (not to be confused with the starter current!), and not every car owner will open the passport for the battery and look for the value of this current.

- for traction alkaline batteries- 3-hour discharge current (0.33C, where C is the nominal battery capacity in A*h);

- for traction acid batteries- current of 1-hour discharge mode (1.0C);

- for starter batteries, acid and alkaline from 1.0C to 1.4C

What is the n-hour discharge current?? That is, this is the current, when discharged, the rated voltage of the battery (for a car battery this is 12.6 V) will drop to the permissible minimum value (again for a car battery this is 10.2 V) for a given period of time (n-hours).

To determine the n-hour discharge current, you need to divide the battery capacity indicated on it by the discharge time.

For example, in order to find out the 20-hour discharge current of a battery with a capacity of 60 A*h, you need to:

I = C/t = 60 A*h/20 h = 3 A.

This means that the manufacturer guarantees that when this battery is discharged with a current of 3 A for 20 hours, its voltage will not drop below 10.2 V.

Thus, for car batteries, the current generated by the load plug should be within 1-1.4 of the capacity specified by the manufacturer.

In practice, for batteries with a capacity of 15-100 A*h, a plug with a current load of 100 A is used, for batteries with a capacity of 100-240 A*h, a plug with a current load of 200 A is used.

Therefore, the most common load plugs for car batteries have a current load of 100A.

Checking the battery with a load fork.

The method of testing a battery with a load fork is quite simple, and I also described it in the article “How to test a car battery.”

However, I consider it necessary to state it here again:

Stage 1. Checking the battery voltage without load.

To do this, disconnect the load from the load plug voltmeter. And using a voltmeter, we measure the voltage on the battery.

In this case, we determine the degree of charge of the battery using the following table:

Stage 2. Checking battery voltage under load.

We connect the load and measure the battery voltage.

We take readings from the load fork voltmeter at the end of the fifth second of measurement. The battery charge level is determined using the following table:

You should not take measurements for more than 6-10 seconds, as this leads to heating of the load-spiral and can lead to failure of the load fork itself.

If the charge level of the battery is different from 100%, then it is necessary to fully charge it using existing methods, which I will tell you in the next issues of ELECTRON magazine. After this, check the battery again using a load fork.

If the percentage of battery charge obtained when testing without load is greater than under load, then the battery is said to “not hold the load.” This means that it is necessary to take measures to restore the battery capacity. And to do this, it is necessary to determine the reason for the drop in capacity and the feasibility of further operations to restore the batteries.

We will talk about how to determine the cause and restore the battery in the next issues of the ELECTRON magazine, so don’t forget to subscribe to new issues of the magazine.

And now a detailed video about working with a load fork,

All car owners understand that the main element of any car is the battery, which ensures the operation of all electrical systems and devices. But, like any power source, the device can fail. In this case, maintenance will be required. One of the effective diagnostic methods is to check with a load fork.

Basic Concepts

A load fork is a device that analyzes the operation of car batteries. The device monitors the open circuit voltage, the batteries under load at the output points, and the overall performance of the battery. The device includes a voltmeter, resistance coils, and in some cases an ammeter. The scope of application of the device is not limited to car batteries; it can be used to take readings from any part of the electrical circuit.

This is a small device in a metal case with several resistances and a voltmeter. On one side, a thick wire is connected to the voltmeter, on the other there is a clamp for connecting the positive electrode of the device to the battery. The negative terminal is connected to a metal pin. The resistance coils are connected with two nuts. The load on each spiral is calculated at 100 A of electric current. Clips on the wires are necessary to connect them to the battery terminals.

There are quite a few types into which the load fork is divided. The device diagram is the same for everyone and is nothing complicated. An important difference between the devices is the voltage measurement range and load rating. Alkaline batteries and acid batteries use different plugs.

How to use the load fork?

Before using the device, the engine must be idle for at least 6 hours; you can check it after overnight parking. The procedure is carried out in two stages. It should be taken into account that 12-volt batteries can be tested using one spiral, and for larger capacities two are used.

A device with an unconnected load is connected to each terminal of the element. The positive terminal is connected to the same charge of the battery terminal, after which they work with the negative elements. The voltmeter readings are recorded.

Meaning of indicators and action plan

• The battery is 100% charged - 13 W.
• Battery malfunction or discharge - 11.5-11.8 W.
• 75% charge - 12.3-12.6 W.
• At 50% the data will be between 12.1 and 12.3 watts.
• 25% (almost complete discharge) - 11.8-12.1 W.

If after checking it turns out that the battery is fully charged, you need to perform the same actions as additional measurements, only you need to turn on the load connections.

Sequence of work:

• the terminal is cleaned;
• the load plug is connected with the correct polarity;
• voltage is measured;
• The resistance is set according to the battery volume.

The load fork is pressed against the battery terminal until it stops for a short time (up to 5 seconds). The battery plugs must be wrapped when performing these steps. If sparks start when you touch the negative terminal, it’s okay - this is normal. However, the heated pin should not be touched with your hands between measurements.

Identifying indicators

The serviceability and full charging of the battery is indicated by the 9 W mark. Indicators less than this figure indicate that the battery is incomplete or broken. In this case, it is necessary to charge and repeat the measurement procedure.

If the battery is working properly, the indicators should return to normal; if this does not happen, detailed diagnostics or battery replacement is required. You should not use the load fork for preventive purposes and very often - such actions can damage the battery.

Making a device yourself

So, the load fork is a powerful tool with a DC voltmeter and two test leads. Of course, this type of device can be found in any specialized store, but with desire and ingenuity, a self-created load fork will become an equally useful device.

A homemade plug is good for measuring energy in 12-watt batteries. Before you start creating the device, you need to measure the voltage value of one fully charged battery jar. Each such jar must have free access. The data obtained is necessary to compile a scale that will show the car’s battery charge in the desired range in the future.

Next, you will need to turn on the microammeter together with the resistor. It is necessary to monitor the resistance; it should be slightly greater than the voltage of one of the battery banks. The scale of the device is changed by applying an alternating direct current voltage to the voltmeter in the required polarity, which is controlled by a reference device.

Formulas for calculations

The instructions for the battery indicate information about the minimum and maximum permissible charge values, you need to know them. The design of the device requires some knowledge of physics, namely the formula for the resistance of the load element of an electrical circuit. It is determined by the formula: R=U/I.

Here R is defined as the resistance value (Ohm), U stands for voltage (V), and current stands for I (A). The power (P) of such a circuit can be found by multiplying the voltage (U) by the current (I). The clamps must have a long endurance, because a large current will pass through them. They are manually connected to the resistor with high-quality wires that can withstand heavy loads.

All parts at the joints must be well soldered using a soldering apparatus. Now you need to connect a voltmeter to the homemade load plug (you can use a microammeter with a small resistor as it). The terminals are marked with the same polarity as on a working voltmeter. The connection points are isolated.

You can build a frame to mount the device on it for ease of use. The materials used for this are exclusively non-flammable; metal is best suited. In this way, a do-it-yourself load fork is created.

Installation Rules

When installing, it is important to follow the basic rules:

• the device is connected to the battery only in the disconnected state;
• It is prohibited to store the plug near other battery-powered devices;
• after work, the room is thoroughly ventilated;
• connection to each jar is carried out separately;
• it is necessary to monitor the current power so as not to damage the elements;
• steel or nichrome is used for clamping;
• The equipment does not connect for long, especially homemade ones.

The task performed by a digital load fork is no different from a conventional device. However, its important feature is the ultra-precise measurement results displayed on the equipment display.

Features and disadvantages of the device

For many years, the heavy load method has been used to test the performance of lead batteries. Devices capable of taking hundreds of amperes of current from a battery and measuring voltage under such a load are still being produced. The voltmeter scale is painted in several colors. When the arrow is in the green area, the battery is considered to be in good condition, red is a sign that the battery needs to be replaced.

The popularity of the fork is due to the qualitative identification of indicators. However, it is not possible to check the battery capacity. Therefore, it is extremely difficult to predict the service life of a product in this way. Another fact that needs to be taken into account: the plug takes a significant percentage of the charge from the battery, so it cannot be used often.

Effectively, such devices help to identify a defective individual bank from a general assembly, and also make it possible to check the battery’s charge to a certain voltage and the ability to withstand the operating current of the battery.

The most accurate data is obtained when diagnosing new battery devices. It is recommended to carry out testing at a time when the electrolyte temperature is positive from +10 to +25 °C. It is not at all necessary to throw away spoiled batteries; there are enough recycling points for such devices. The replacement resistance must match the capacity and type of battery.

A testing device, presented in the form of a load fork, is one of the important devices used in the work of an auto electrician. However, not all car owners are ready to constantly contact a car service; to do this, they need to make this device themselves.

Load fork, operating principle

Self-assembly of the device is not a task of increased complexity. Before assembly, you need to understand what the device is intended for and what it consists of.

Device

A load fork is a device with which it is possible to test a power source in a mode similar to its normal operating conditions. In most cases, when factory assembled, the device consists of a dial or electronic voltmeter, as well as one or two resistances for which metal spirals are installed. Measuring probes with terminals for connecting to the battery are attached to the ends of the spiral.

Sometimes an ammeter is installed in the load fork design. The device itself is presented in the form of a metal or plastic box with outgoing wires and clamps. Modern models are equipped with digital meters, liquid crystal displays, and also have several resistance coils with a switch for combining the load to the battery.

The device is used to check the voltage value on a power source with electrolytes based on acidic and alkaline compounds. When examining individual elements of cans, special forks with simplified characteristics are used. Using this device, it is possible to check the performance of not only the battery, but also any element of the electrical circuit. The measurements are carried out with the power connected, as well as with the electromotive force turned off. Not only the voltage can be controlled, but also all the necessary parameters, all depending on the complexity of the plug design.

Application of load fork

Using this device it is possible to perform the following actions:

1. Determination of the storage time of the internal energy reserve. This parameter depends mainly on the internal capacity. Common models with a value of 50 A/h are able to maintain their parameters for 140 days under normal operating conditions. When the power source is connected to the network, the time is reduced by almost half. Most losses occur when the alarm system is working.

It is important to know! In winter, the battery discharges when the alarm is running on average within 15 days.

1. Measurement of state of charge. In this case, the value of 11.7 V indicates that the battery is discharged. Full charge 12.7 V, half charge 12.3 V.
2. Determination of possible charge retention time. When the reading on the load plug shows a value below 12 V, it indicates that it is necessary to restore the charge.
3. Monitoring the short circuit between the plates in the battery. If there is a short circuit, the voltage drops to 9 V. When charging, the electrolyte boils.
4. Determination of generator output parameters. Deviations from normal operation can lead to starting problems and battery failure.
5. Monitoring the sulfation of electrode plates can be done if an ammeter is included in the package.

Difference between models

Load forks differ from each other in several ways:

• clarity in obtaining evidence;
• type of measuring device;
• resistance of resistors or spirals;
• Operating temperature range;
• measured voltage range;
• current ratings;
• different media of electrolytes used.

How to check correctly

The load plug is designed to test power supplies with a nominal power value of no higher than 12 W. However, it is possible to use increased power in the network if several resistors are used. To carry out an accurate check, the following procedure must be followed:

• measure the voltage at the terminals without load;
• the obtained value is compared with the passport data;
• when fully charged, connect the load;
• after 5 seconds, take voltmeter readings;
• A working battery should show a value of at least 9 V.

DIY load fork

Simple to make and inexpensive, the device will be useful in the garage of any car enthusiast. With the help of this device it will be possible to carry out continuous diagnostics of the power source, as well as the generator. If you do not have the necessary amount to purchase a load fork, you can make it yourself.

Material used

When making a fork, you may need the following materials:

• to measure voltage you will need a voltmeter, if we use an analog one, then it should have a measurement limit of up to 20 V;
• insulated wires up to 6 mm thick, designed for high current values;
• at the end of the wires you should use special powerful clamps made of chrome steel;
• frame made of non-flammable materials;
• holder made of rubberized steel.

Important! When making a homemade load plug, it is recommended to use wires and devices designed for maximum operating current values.

Scheme

Single Spiral Load Fork:

Load fork with two spirals:

where R is resistance in the form of spirals or a set of resistors;

S - switches or switches;

V - voltmeter device.

When measuring a battery with a capacity of up to 100 Ah, one resistance must be used; when testing a battery with an internal capacity above 100 Ah, two or more resistances are used.

Instructions on how to make a load plug to test the battery

When manufacturing using one of the common methods, you must follow the following instructions:

• Before carrying out measuring manipulations, it is necessary to ensure access to the battery terminals. Then readings are taken using a voltmeter in no-load mode.
• To determine the required resistance, you should refer to the passport characteristics; from them we will find out the nominal values ​​​​of voltage and electric current. According to the formula:

where R is additional resistance, U is voltage, I is current under load.

• At the next stage, it is necessary to connect additional resistance. The value should be slightly greater than the internal resistance in one of the battery cells.
• We connect the probes from the voltmeter to the ends of the wires with special clamp terminals.
• All devices and switching elements are placed on a PCB plate and securely fastened. This material is non-flammable and is considered a reliable insulator. In some cases, a ceramic base is used.
• The very last step is to install a handle with rubber on the frame. Rubber is used as an insulating material.

For the simplest method, you need to do the following:

• You should use the ground button from the old car.
• Select two additional resistances from old fans.
• Connect all switching elements.

The resistance block used in this case has internal protection, which is built-in fuses that operate when the internal temperature rises sharply.

The designs of the simplest devices described above for testing power supplies under load are quite simple. In the process of improvement, it is possible to install an ammeter and a stopwatch on the same frame.

If a car driver is sure that there is enough fuel in the tank, but the car does not start, the first thing that comes to mind is a problem with the battery. The battery is one of the important components of electrical equipment in automobile transport. Its main function is to help the starter start the engine. If the car does not start, experienced car enthusiasts recommend checking the battery. There are quite a lot of methods, but today we will tell you how to properly test a battery with a load fork, about the types of this device, and also how to make a load fork for batteries with your own hands.

The load resistance of the fork is in the form of a spiral.

So, a load plug for testing a battery is a device whose main functional property is to measure the discharge level of the battery. The design of this device is quite simple - a voltmeter and a certain number of load spirals are installed in a metal case, which act as a resistance. The negative (minus) electrode of the voltmeter is connected to a metal pin (it can be seen on the back of the metal case), and the positive electrode is connected to a wire of a sufficiently large cross-section, which ends with a special clamp. It is the clamp that is connected to the terminals of the battery during the diagnostic process of the battery.

Why do you need to check your battery?

As mentioned above, the battery is a device responsible for starting the engine of any vehicle, and its serviceability determines whether you drive a car today or walk. Unfortunately, buying a new battery does not guarantee that it will be in good working order, so for peace of mind, it is better to check the battery with a load fork when purchasing. How to carry out the check will be described below.
If you haven’t gotten around to making a load fork, then there are several other ways to test a battery without a load fork.
The main ones:

When purchasing a battery, it is necessary to test it with a load fork.

• external (visual) inspection of the battery;
• electrolyte level measurement;
• diagnostics of electrolyte density using a hydrometer;
• check using a voltmeter as well as a multimeter.

How to make the right choice

A varied assortment of load forks often confuses those who want to buy this device. How to understand which plug for testing the battery is better, how not to make a mistake with the choice?
First of all, it is worth noting that, despite the wide range, plugs differ in several factors: measurement range, load size, battery type.
Types of load forks for testing batteries can be classified according to the following principle:

• measurement range;
• load size;
• type of battery: acid or alkaline.

In addition to the above types, load forks can be classified according to the type of indicator. In modern versions of this device, liquid crystal indicators are already installed. It should be noted that the answer to the question, how much does a load plug for a battery cost, will also depend on the functionality of a particular type of device.

How to use the device

Checking battery voltage with a load plug without load

It is no secret that new drivers, and especially female drivers, are wary of any problems related to the internal structure and components of the car. However, we want to reassure you that working with this device is quite simple.
So how to use a battery load plug?
There are two options for testing the battery with a load fork. Let's take a brief look at each method of how to test a battery with a load fork.

Test without load

Before checking the battery with a load plug, you must disconnect the terminals and wait 6 hours.

For this diagnosis, it is necessary to carry out preliminary work - disconnect the battery from charging and be sure to wait for at least 6 hours to pass. Then the “positive” terminal of the device should be connected to a similar terminal of the battery, and the “negative” pin is touched to a similar terminal. Take indicator readings. This plug method will show you the charge level of the battery:

• when the voltmeter value is in the range of 11.5–11.8, it indicates that the battery is completely discharged;
• readings varying in the range of 11.8–12.1 indicate that 25% of the charge remains;
• numbers 12.1–12.3 means the battery is half charged;
• indicators 12.3–12.6 – the battery has 75% charge;
• 12.6–12.9 – these numbers indicate a full (100%) battery charge.

Load test

Checking the battery voltage with a load fork under load

Diagnostics of the battery under load should be carried out for no more than 5 seconds.

This is the next stage of battery diagnostics. It is no different from the first method, the only exception is that you connect the appropriate load to the load plug. The steps are similar for testing without load. Please note that diagnostics must be carried out within no more than 5 seconds. If the readings on the plug indicator show more than 10.2 volts, it means that the battery is charged, otherwise. If the results of the first and second diagnostics are strikingly different, we can conclude that the battery is faulty.

Making a load fork yourself

Precisely because the load fork for the battery has a rather high price, experienced car enthusiasts prefer to use a fork of their own making. The whole process of how to make a load fork to test a battery can be divided into the following stages:

• Determine the voltage in one bank of your battery in a fully charged state. This can be done experimentally, or read in the battery manual. An important factor is to make sure that you have access to all banks;
• using a microammeter and a resistor, gradate the future plug;
• calculate the resistance of the resistors;
• connect the probes and solder the mounting points well. Be sure to indicate the polarity of each probe;
• secure all parts of the future plug in a metal case.

We hope that we have helped you at least a little to study the topic “Load plug for a car battery”, and now you can choose or make yourself exactly the device that you need.

A load fork is an extremely necessary device for testing batteries. There are many types of this device. The most convenient and technologically advanced ones are the most common and arouse the deserved interest of potential users.

Load forks for battery testing

A load plug is a device designed to determine the overall performance of the battery, as well as the degree of its charge (discharge). This device performs this job quite efficiently. However, it is impossible to check with a fork and also to detect the sulfation that has begun in it. . Because of this, based on a battery test, it cannot be used to make a prediction about the battery life.

In addition, during the testing process, the plug removes a significant charge from the battery and, if used frequently, can lead to a significant reduction in its service life.

In addition to testing the battery, this device allows, using a built-in voltmeter, to diagnose the electrical network and its elements (for example, a generator) by measuring the voltage in a selected area. In general, battery load plugs consist of a voltmeter, a coiled load, and test leads (or wire with a clamp and test lead) to connect to the battery terminals. When testing the battery under load, the coil is connected in parallel to the voltmeter. When the load spiral circuit is open, the plug is used as a regular voltmeter to measure the voltage level in the range provided for the device.

The most common types of forks

The most common are VN-1 and NV-01. They are designed for testing 12 V batteries with a capacity of up to 190 Ah. Load fork VN-1 has the following main characteristics:

• application temperature range from +1°C to +35°C;
• spiral resistance 0.1 Ohm ± 15%;
• The operating mode for load measurement is intermittent and short-term: measurement duration – 5 s, pause – 15 s.

The VN-1 load fork is currently not used as often as before. It was replaced by more modern and accurate NV-01 devices:

• measurement accuracy 2.5%;
• The measuring range of the voltmeter is 0–15 V;
• the load current for a battery with a capacity of 15–100 A*h is 100 A, with a capacity of 100–190 A*h it is 200 A;
• application temperatures from –30°С to +60°С;
• spiral resistance 0.1 Ohm ± 5%.

Load plug NV-02 – for testing 12 V batteries with a capacity of 15–240 Ah. Characteristics:

• measurement accuracy 2.5%;
• The measuring range of the voltmeter is 0–15 V;
• the load current value for a battery with a capacity of 15–100 A*h is 100 A, with a capacity of 100–240 A*h it is 200 A;
• spiral resistance 0.1 Ohm ± 5%;

Devices VN-1, NV-01 and NV-02 are equipped with a pointer voltmeter.

Fork NV-03. This device is identical to NV-02, but has the following differences:

• higher measurement accuracy of 0.5%;
• The measuring range of the voltmeter is 0–16 V;
• digital voltmeter equipped with a liquid crystal display;
• push-button switching of operating modes.

Universal NV-04 and powerful NV-B

Load plug NV-04 - for testing batteries with voltages of 12 V and 24 V with a capacity of up to 15–240 Ah, as well as for individual testing of one individual battery element with a voltage of 2 V. Characteristics:

• measurement accuracy 0.5%;
• The voltmeter measurement range is 0–32 V;
• load current at 12 V – 50 A, at 24 V and 2 V – 100 A;
• spiral resistance “2 V” – 0.02 Ohm ± 5%, “24 V” – 0.2 Ohm ± 5%;
• use temperatures from –20°С to +60°С.

This load plug allows you to check the charge level and serviceability of not only the entire battery, but also each of its elements separately, which in some cases is extremely necessary. In addition, this plug has a permissible load measurement time (when the coil is connected) of 9 s, as opposed to 5 s for other devices. NV-04 has a digital voltmeter equipped with a liquid crystal display and push-button switching of operating modes. It is universal in its functionality – it allows you to perform all types of tests without exception.

Load plug NV-B - for testing only individual elements of 1.2 V and 2 V batteries up to 500 Ah. That is, the battery itself can be of any voltage (12 V or 24 V).

Characteristics:

• equipped with an M1001M magnetoelectric voltmeter, the arrow of which deviates from the center in both directions;
• The measuring range of the voltmeter is 3–0–3 V;
• instrument scale division value 0.2 V;
• spiral resistance 0.02 Ohm ± 5%;
• load current is 100 A.

The NV-B load fork is the most powerful of those presented. Its disadvantage is the inability to test the entire battery.