Instructions for using a hydrometer. A hydrometer for electrolyte, antifreeze, antifreeze and washer fluid with a built-in thermometer and a device for collecting fluid (motorist’s kit). How does this meter work?

A car battery is a vital organ in its overall electromechanical system. Without it working, start the engine, in the usual way, impossible.

So that your battery, as usual, does not play a cruel joke on you at the most inopportune moment, you need to periodically check its density. This article will focus on serviceable batteries.

Checking battery density with a hydrometer

To understand this issue, you must first understand what a device for checking the density of the battery electrolyte is - a hydrometer.

A hydrometer is the simplest device used to measure the density of a liquid, and its operating principle is based on the well-known Archimedes law.
He looks like this.

An ordinary glass tube, the upper part of which is narrowed and has a graduated scale. Bottom part The tube is wide; it contains shot or mercury, which is poured in a strictly defined amount during calibration of the hydrometer.

The device, as a rule, is sold in car dealerships as a set with a rubber “bulb” for collecting electrolyte and a measuring flask in which the hydrometer itself is located.


Let's take a closer look at how to check density car battery?

• First of all, place the battery in a clean place and flat surface, do not forget that electrolyte is an acid and any drop spilled on clothing will ruin it forever. And if it gets on skin it will cause chemical burn.
• Clean the battery from dirt. Any dirt that gets into a jar of electrolyte can change the density in this container, which will inevitably lead to damage to the entire battery.
  After removing the lids from the cans, check the electrolyte level and top up if necessary. Most often, distilled water is added, but sometimes in a case that we will talk about below, it is necessary to add electrolyte.
• Another prerequisite before checking the density is to fully charge the battery.

Important! During the battery charging process, hydrogen and oxygen gases will be released from the cans. A large concentration of these gases can lead to an explosion, so the room must be well ventilated.

The charging process is not fast, so you will have to wait for some time (5-6 hours). It all depends on the level of discharge of your battery and the capabilities of the charger.

The service life of a serviced car battery depends on various factors. However, when proper care it manages to significantly extend this period. An important factor in such a situation is to ensure optimal value density for electrolyte. In this case, you will need to know how to use a battery hydrometer.

Thanks to special device– a hydrometer allows you to measure the degree of acidity of the solution for each cell in the battery. In fact, density refers to the ratio of the mass of mixed acid with distillate to the total volume of the resulting solution.

The usual check of the density of the electrolyte in a battery with a hydrometer is based on the classic physical law Archimedes, when a body immersed in a liquid displaces from a vessel a volume of liquid equivalent to its own volume. Thanks to the laws of hydrostatics, it is possible to calculate with a high degree of accuracy the acidity value in a particular liquid. Usually the parameter is indicated in g/cm 3, and is defined to hundredths.

Visually, a hydrometer for electrolyte is a transparent glass wide flask, inside of which there is a measuring scale. For the fence, a rubber bulb is installed in the upper part of the device. Working with such a chemical unit is quite simple.

The components in most designs are parts such as:

• rubber bulb;
• hydrometer block;
• a glass pipette containing the device;
• sealed plug;
• fence part.

Some types of hydrometers are universal. With their help, you can additionally determine the temperature of the liquid.

Method of using the device

Before checking the battery density with a hydrometer, you need to familiarize yourself with the operation of the device so as not to get chemical burns and achieve the correct results. Usually, for measurements, preliminary fluid is taken from the battery cans.

It is important to know that each car battery can is an independent container for liquids, so measurements will need to be taken for each container separately.

Safety precautions must be observed when pumping liquid for testing. Acid-resistant rubber gloves and safety glasses are required. An apron made of rubberized material or a special protective robe helps protect your clothes. To select the required volume, we use a glass tube, since this material is chemically neutral to acids.

The step-by-step algorithm for measuring density with a hydrometer consists of the following points:

• lower one end of the glass tube into the neck of the open battery can;
• part of the liquid will penetrate inside the tube, and its level will be leveled with that remaining in the container;
• Close the top hole tightly with your fingertip and slowly remove the tube;
• lower the end of the glass tube into the flask prepared for measurements and then open it top part tubes so that the liquid flows into the vessel;
• Since the hydrometer works correctly only in a certain volume of liquid, we repeat the procedure many times until required quantity for measuring;
• We place the hydrometer inside the flask and wait for it to level, since we need the number indicated by the line of the liquid surface;
• after stabilization, the desired density of the liquid will be known.

After measuring, return the liquid back to the jar in the same way as it was taken. We carry out operations with each capacity from the battery in order to obtain complete information about the condition of the battery.

When working with a hydrometer, you need to squeeze the bulb and then immerse the pipette in the liquid so that it floats there like a float in a vertical position. After compression, the rubber is gradually loosened to smoothly fill the container. The measurements will be accurate when the float does not come into contact with the walls of the vessel. If it is stuck, the readings obtained will be unreliable..

Upon completion of work, rinse the device with distilled water. This will help extend its service life and eliminate measurement errors.

Important Factors

For a car battery, problems will be minimized when its density at 25 C is 1.28 g/ml. This parameter typical for all new batteries leaving the factory. When a lower density was found in one of the cans, this is evidence of a probable short circuit, which occurred due to the contact of lead plates with each other.

If you detect low density in one of the cans, you should understand that the probable causes lie in such events as:

• the battery has suffered a deep discharge and will not be able to perform further operations as usual;
• a sulfation stage occurred inside the cavities, which became a problem for further chemical reactions;
• the battery worked for a long period without additional recharging from the generator, which could fail;
• physical wear of the battery has occurred, which does not allow it to be used for its intended purpose in the future;
• the low quality of the solution and other components is due to an unscrupulous manufacturer or the use of counterfeit products.

In the case when it is possible to bring the density to the optimal value, it will be possible to ensure the battery’s performance.

Popular brands of hydrometers

The domestic market offers different models of battery solution density meters. Those interested can even discover an electronic electrolyte hydrometer. The main differences lie mainly in the quality of the component materials used.

IP-1

Among the popular devices classic shape What stands out is a device with a set of plastic cylinders inside. Opposite each of them is the density value. After filling measuring capacitance the set of cylinders begins to float. You can read the current density value from the cylinder that rose last.

The measuring range of the model is limited. It can give results if the density of the liquid fluctuates in the range of 1.19–1.33 g/cc. Minimum price division is 0.02 g/cc. Although the measurement accuracy of such a unit is low, it is popular among car enthusiasts. Success lies in affordable prices. The price is a little over 100 rubles.

Orion AR-02

The chemical device is produced at a domestic enterprise located in St. Petersburg. detailed instructions describes how it should be used. It is important to take precautions when working with it.

You can find a meter in popular stores for 150 rubles. The manufacturer provides a six-month warranty on the glass device.

Sparta 549125

The cost of the device is about 200 rubles. Produced in China under a German license. It works in the range from 1.16 to 1.3 g/cm 3 . The pear and fence part are made of practical, durable materials. The manufacturer provides a one-year warranty on each product. There are floats inside.

01-03-2012

The history of the birth of the hydrometer. Purpose and classification of hydrometers.

This ingeniously simple instrument (roughly speaking, a float with a scale) for determining the density of a liquid was invented by the Greek Hypatia, a mechanic, philosopher, mathematician, astronomer and philosopher, who lived in the 4th-5th centuries in Egyptian Alexandria. Hence, in general, the name itself: araios plus metreo or metron, i.e. measure (to measure) liquid. By the way, besides this physical device Hypatia also invented the astrolabe, the still, and the planisphere (this is a flat, movable map of the stars in the sky).

However, many historians consider A. Baume, a French chemist of the 18th century, to be the author of the invention. In any case, modern ones and those used almost 300 years ago are very similar in appearance. The same tube made of thin glass, filled (weighted during calibration) at the bottom, in the wider part, with mercury or metal balls. The calibration weight is fixed with a binder - sealing wax, resin, etc. The upper, narrower part of the device has a scale (percentage or density values).

The technical encyclopedia, medical, explanatory and other dictionaries provide different interpretation The words hydrometer - the essence of the device and the principle of its operation (hydrostatic law) do not change. This only indicates the breadth and diversity of its application.

So. By using of this instrument determine the density of a liquid (including solutions and suspensions, i.e. they can determine the concentration of a substance in a solution). These devices are sometimes called densimeters (densi in Latin - dense), however this definition not entirely correct: rather, a hydrometer is one of the types of densimeters. A more correct name: constant mass hydrometers. There are also constant volume hydrometers. What are we talking about?

The density of a substance depends on the mass of the hydrometer and the volume that it displaces when immersed. A constant mass hydrometer floats freely in a liquid and the density or concentration is assessed on a scale. A constant-volume hydrometer has a variable mass - as it increases (with the help of special weights placed on the upper plate-cup), the device is immersed in the substance to the mark. By dividing the mass of the weights by the volume of the substance displaced by the hydrometer, its density is calculated. The first such device was created by the German physicist Daniel Gabriel Fahrenheit.

According to GOST 18481-81, hydrometers are classified as follows (the letter “T” means that the hydrometer is equipped with a thermometer, because density depends on temperature; also devices of the same type may differ in measurement range):

• AEG - hydrometer (means the same as a hydrometer) with a thermometer - for measuring the mass fraction of ethylene glycol in antifreeze (determining the freezing point);
• AG - to determine the granulometric composition clay soils;
• AK - for measuring the density of acids;
• AM - for measuring the density of milk, whey, buttermilk;
• AN - determination of the density of oil and petroleum products;
• ASP - determines volumetric concentration ethyl alcohol in aqueous solution;
• AU - measurement of urine density;
• AE (AR) - determines the density of the electrolyte, i.e. battery discharge level;
• Caller ID - hydrometers general purpose: measure the density of liquids (including solutions of salts of acids, alkalis, acids, concrete, solvents, etc.). They can be universal, or in the form of a set of hydrometers;
• AS - determination of sugar concentration in an aqueous solution.

A hydrometer is a device used to measure the density of a liquid, based on the work of Archimedes’ physical law. In most cases, the device is a regular glass flask with a printed scale, which is hermetically sealed and filled inside with metal shot to calibrate the mass. The tube is thicker at the bottom and tapers towards the top, making it resemble glass bottle with an extended neck. Hydrometers are designed to measure a specific liquid, so if the device is calibrated for one substance, it will not work with another.

How does a hydrometer work?

The operating principle of the device is based on the hydrostatic physical law. According to it, when a body is immersed in a liquid, it is acted upon by a buoyant force equal to the mass of the liquid that was displaced by the body. Different liquids have different densities, so a body immersed in them is pushed out with different forces. In some substances it can sink, while in others it will float on the surface.

The principle of operation of a hydrometer is that its mass is calibrated to the buoyant force of certain liquids. Due to the presence of a weighting material in the lower part, the device, when immersed, takes vertical position like a float on a fishing tackle. There is a scale on the side surface of the instrument bulb. In order to determine what level of density of a substance, you need to look at what indicator on the scale the liquid line reaches.

If you install a device in a substance for which it is not calibrated, the device may sink, lie on its side and float on the surface, or stay upright but give an incorrect density reading. To take accurate data, when installing the hydrometer, you should wait until it is finally balanced and does not fluctuate.

Features of the scale

Although the hydrometer is very simple device from a technological point of view, but with its help you can take various indicators from liquids. In particular, the scale available in a glass flask can be graduated with various indicators:

• Liquid density.
• Percentage of mass content of impurities.
• The percentage of solute concentration in the bulk fluid.

Types of hydrometers

Although outwardly all hydrometers are almost the same, they still differ depending on what substance they are tuned to. These devices come in the following types:

• For petroleum products.
• Lactometers.
• For electrolyte.
• Alcohol meters.
• Medical.
• Sugar meters.
• Salt meters.

For petroleum products

A hydrometer used to change the density of petroleum products allows you to determine the indicators of oil, gasoline, diesel fuel or kerosene. Thanks to its use, it is possible to determine the compliance of the fuel with the declared characteristics and the presence of unacceptable impurities that reduce combustion efficiency or contribute to an increase in the formation of burning.

Lactometer

Used to check the density of milk. Using this device you can determine the presence of thinners. The lactometer detects milk to which water has been added. The device also allows you to identify a product that is a liquid with a dye, which they are trying to pass off as natural milk. Most lactometers show fat percentage, but when measuring counterfeit or very low-quality products, they simply lie on their side.

For electrolyte

A device for measuring electrolyte density is used to diagnose batteries. It is also available for testing parameters various acids. With its help, you can determine the state of the electrolyte and decide on the need to replace it to restore the capacity battery.

A hydrometer for measuring electrolyte density is characterized by the presence of an additional external flask with a bulb. Since the electrolyte is an acid, skin contact with which is undesirable, this device has been designed with safety requirements in mind. To take measurements of the battery, you need to unscrew the caps on it, providing access to the banks. After this, using an external flask with a bulb, electrolyte is collected from it. The hydrometer inside the flask floats up. Through the transparent glass of the outer flask, the density level of the electrolyte can be determined.

The design of such a hydrometer is resistant to acidic environments, but after use it still needs to be washed in clean water. This is due to the fact that aggressive substances stored on the surface can cause burns in the future if you touch the tool. In addition, the flowing drops of acid corrode the metal and other materials they fall on.

Alcohol meter

An alcohol hydrometer allows you to determine the strength of an alcoholic drink. This device operates in a different range. In this regard, if you need to use such a device, when purchasing, you should start from what kind of drink you will have to test. If you drink vodka, whiskey and other strong drinks, then you should give preference to devices with a measurement range of about 40 degrees. It should be borne in mind that such a device will not be able to show the alcohol content in wine. For low-alcohol drinks, you need to use lightweight hydrometers that have undergone specialized calibration.

It is worth noting that the alcohol meter costs mere pennies, so it has found its use not only in industrial production, but also in everyday life. Usually it represents the simplest design in the form of a glass flask, the bottom of which is filled with metal balls. In order to obtain accurate data, certain temperature conditions. When the alcoholic liquid cools or overheats, the data is distorted. It is best to measure at a temperature of 20 degrees, which is the reference value.

Medical

Medical hydrometers are used to analyze the density of urine. They are used in laboratories. By using of this equipment you can assess the condition of the urinary system, as well as the quality of water that a person constantly consumes. Based on density parameters, it will be possible to make a preliminary diagnosis of the presence of stone formations in the kidneys.

Saccharometer

A saccharometer is primarily used to analyze wines and fruit juices to determine their sugar concentration. The devices are used in cooking in the preparation of drinks and cocktails, as well as in the production of alcoholic beverages. Saccharometers are often offered for sale in combination with alcohol meters. The set may also include a thermometer to measure the temperature of the drink.

The use of a saccharometer is especially important in the production of alcoholic beverages resulting from fermentation. Periodic reading of sugar parameters from the wort allows you to determine the moment when fermentation dies down, or to find out whether it is necessary to add a new portion of sugar to continue the process.

The sugar meter has also found application in industries such as fruit juice production, as well as gardening. It can be used to determine the degree of ripeness of fruits and berries. To do this, squeeze out a small amount of juice, after which the concentration of sugar in it is measured. Based on the data obtained, a decision is made on the advisability of harvesting the crop or extending its ripening period. It is not difficult to navigate the degree of ripeness, since most varieties garden trees in the description they have accurate data on the reference values ​​for the concentration of sugar in ripened fruits.

Salt meter

Salinity meters are used to measure water density parameters. With their help, you can determine the condition of water and its suitability for consumption. Similar devices are used in fish farms, as well as by specialists who keep marine aquarium fish. The health of the fish depends on the density parameters, so periodic testing of the water is required, which is performed by a salt tester. The device is not a panacea, since in addition to density, there are many other parameters that need to be monitored using other equipment or chemical tests.

The salt meter is often used in cooking, as well as Food Industry. It helps control the salt concentration in marinades. This is especially important during further smoking of meat. The presence of a salt meter allows you to work with large volumes of liquids, when it is difficult to determine how much salt to add.

Differences between devices of the same type

When purchasing this device, you should pay attention to the level of error indicated by the manufacturer. This indicator is measured as a percentage. If the device is needed to perform simple tasks that do not require extreme precision, then almost any device, even from the lowest price segment. If taking measurements is a responsible undertaking, then measuring device must be appropriate.

If necessary precise measurement You should choose a device with a long scale. Typically, cheap models of hydrometers have a dense gradient, so when taking measurement parameters it is difficult to visually determine exactly what result was obtained.

To obtain the most accurate measurement results, it is important to use the device correctly. First of all, when testing, you need to collect the liquid in a separate container with a high neck. For this, a wide transparent test tube or tall glass is usually used. After this, the hydrometer itself is placed directly into this dish. It is necessary to ensure that the device does not touch the walls, as this distorts the accuracy of the measurement.

For modern vehicle the battery is an important component of the overall electromechanical circuit. Without it, it is impossible to start the power unit of the car. The main indicator of battery performance is its density, which is easy to measure in a private garage.

1 Battery density - how important is this characteristic?

Rechargeable lead-acid batteries (AB) are used in most modern cars. They represent a source of current in which certain chemical transformations occur that are reversible. A conventional battery has electrodes, plates and a special converter (separator) installed in the device body, as well as a cover with terminals and outlet openings. The battery operates using an electrolyte - a composition consisting of sulfuric acid and water (distilled), having a standard density of 1.23 to 1.29 g/cm³. It is with this indicator that the battery copes with its tasks without any problems.

The contact of the lead plates with the electrolyte leads to the appearance of a voltage of 12–13 V in the device. During operation, the battery gradually drains. Therefore, it requires regular recharging. At the same time, the battery discharges faster in cases where the electrolyte density decreases. This leads to deterioration in the functionality of the device and its premature failure.

A decrease in density is most often observed when the electrolyte boils or a significant increase in its temperature and at.

If you do not pay attention to the condition of the battery, it will require replacement much before the expiration of its guaranteed service life. To extend it, it is necessary to make periodic measurements of the electrolyte density. You can perform this operation yourself using a fairly easy-to-use device called a hydrometer. Next we will talk about it in more detail.

2 Hydrometer - a faithful assistant to the motorist

A hydrometer is a basic device used to check the density of a liquid. Structurally, it is made in the form of a glass tube narrowed on one side with divisions applied to it. The other part of the hydrometer is wider. When calibrating the device at the manufacturing plant, a certain amount of mercury or shot is poured into it. Hydrometers are usually sold complete with a measuring flask and a special rubber bulb. The latter is necessary to remove a small volume of electrolyte from the battery for analysis.

It is easy to check the density of a car battery using the described device. We proceed according to the following scheme:

1. Fully charge the battery.
2. We are waiting for 6 hours.
3. In compliance with all safety standards, we dismantle the battery and install it on a flat, clean surface (for example, on a workbench in the garage). We act very carefully. Remember that there is acid inside the battery. One drop of it can cause a serious chemical burn on the body.
4. Remove dust and dirt from the battery. Cleaning should be done thoroughly. One piece of dirt entering the battery can damage it.
5. Remove the cover from the battery.
6. We take the hydrometer and lower it (strictly vertically) inside the first battery jar. We suck out a portion of the electrolyte from it by pressing the rubber bulb.
7. On the scale of the device we look at the density of the electrolyte.
8. We collect liquid in the remaining jars in the same way, recording the readings obtained.

On most hydrometers, the level of permissible (recommended) density is marked with green stripes. In cases where the measured indicator is between them, no additional actions need to be taken. If the density does not meet the standards, this problem will have to be corrected. As you can see, any motorist can use a hydrometer correctly. The main thing is to be careful when dismantling and inspecting batteries, performing all the operations described above while wearing gloves that protect your hands from chemical influences. Let us add that it is advisable to check the battery density every 3-4 months. Then we won't have any problems with the battery.

3 We equalize the density of the electrolyte - we can do it without auto repairmen!

If measurements show a low density of the working fluid in the battery, the situation can be corrected in several ways. First, let's try to simply recharge the battery using this algorithm:

• We charge the battery for 10 hours with a current 10 times less than its density. Everything is simple here. For devices with a capacity of, say, 70 A*hour, we take a current of 7 A, 60 A*hour - 6 A.
• We charge the battery for 2 hours with half the current (3.5 or 3 A).

Often these two actions are enough to equalize the density. We measure the battery voltage after carrying out these procedures. When it does not exceed 14.4 V, the problem is solved. If the voltage value is higher, add distilled water to the battery according to the usual scheme.

In cases where recharging does not lead to the expected result, drain all the old electrolyte from the problematic jar and fill it with new working fluid. There are several nuances here. The spoiled electrolyte must be drained very carefully. The battery can be turned on its side, but never upside down. Before filling the new composition, be sure to rinse the jars with clean water.

You can also increase the density of the electrolyte by adding a more concentrated solution to the battery. We proceed as follows. We take a certain amount of electrolyte from the jar. Drain half of the liquid. Instead, add a composition with a density of 1.25–1.31 g/cm³, pour the “reinforced” solution back into the jar. After this, you will need to shake the battery in order to thoroughly mix the new electrolyte.