Checking the power tool: frequency, timing, method

Any construction and repair is not complete without hand tools, this simplifies and speeds up its implementation. At the same time, it is the portable power tool that is most often used as the most reliable and mobile. Electric energy is one of the most widespread around the world, it is used both in domestic and industrial conditions. However, not every craftsman knows that an electrical tool must be checked regularly so that it does not cause an accident caused by electric shock to a person or an explosion (fire) when working in hazardous fire hazardous conditions. In this article, we will tell you how a power tool is checked, how often it should be done and who should do this type of work.

Electrical tool classification

When operating an electric tool, it is worth knowing that, according to the current GOST, it is divided into several classes of protection. The inspection of a portable power tool, its frequency and method, directly depends on this.

• 0 - has only working insulation without grounding devices and connections;
• 01 - there is working insulation and a grounding element, but the cord itself, which the tool is equipped with, does not have a grounding wire;
• 1 - has working insulation and a grounding element, which is connected through a cable with a corresponding terminal;
• 2 - equipped with double insulation, that is, electrical wiring and live parts are insulated, and the body is made of a dielectric material;
• 3 - this class of the power tool is connected to a low safe voltage - no more than 42 Volts, while the devices are not subject to grounding.

Most often, in everyday life and at the enterprise, workers use class 2 power tools, since it has sufficient insulation so that a person is not injured.

Instrument Inspection Technique

It is allowed to use tested household and industrial power tools. For this, a clear algorithm has been developed that must be followed by everyone who wants to work with it. At the same time, you need to clearly understand the difference between verification and verification.

Verification - these are tests that are carried out in special laboratories located at each large enterprise. The tests include:

1. Determination of the presence and health of the grounding circuit by using a special ohmmeter - one end of the device is connected to the terminal on the plug, and the other to the ground located on the instrument itself. Measurements should show no more than 0.5 Ohm, which satisfies the safety conditions for using the instrument.
2. Measurement for the integrity and quality of insulation is checked with a megohmmeter at a voltage of not more than 500 V for a power tool designed for an operating voltage of 220 V. You can not twist it quickly, this will be enough to see the insulation resistance of the tool. In this case, be sure to remember to press the button that turns on the electric tool. The device should show an insulation resistance of more than 500 kOhm, if this value is less, work with it is prohibited.
3. Then a trial test is carried out during idling for 5–7 minutes.

An overvoltage test can also be carried out on the power tool. In this case, the tool, with a voltage of up to 50 Volts, is tested with a test voltage of 550 V. If the tool is designed for a voltage higher than 50 V, but with a power of up to 1 kW, the test voltage should be 900 V, above 1 kW - 1350 V. The tests are carried out within 1 minute.

Examination - carried out by visual control and inspection. You need to check not only the case, but also the cord connecting it to the power source. Pay attention to:

1. The integrity of the case, it can be cracks and breaks.
2. The supply cable, there should be no visible drying out, damage, chafing, as well as traces of burning and heating. Particular attention should be paid to and check the points of entry of the electric cord into the case and to the plug.
3. The plug and its contact part, which will be connected to the network, are inspected and checked for integrity.

The check should be carried out before starting work, and before switching on after moving to another workplace. Naturally, professional laboratory verification is performed only at large enterprises and firms, in living conditions, the employee, at least before work, should carefully examine the power tool.

If we talk about what the timing of the verification of the power tool, then according to the existing regulatory rules, periodic verification the tool should be at least every year, and it is necessary to check the power tool, as indicated earlier, before each application. If manual electrical equipment is used in extreme climatic and industrial conditions, it is recommended to check it with a megohmmeter at least once every 10 days.

An important point! When checking the tool at the enterprise, first of all, you need to look at the date of the test. If the date is overdue or there is no tag on the test of the power tool at all, then it is prohibited to operate it - it must be removed and handed over for testing.

Registration and accounting of verification

Power tools used in enterprises for professional purposes must be numbered and entered in the register. The management of the enterprise and the structural unit needs to organize a clear record of the storage, operation and inspection of manual electrical equipment. All the necessary information is recorded in a special prepared journal, and a corresponding protocol is issued based on the results of verification and verification. And also a mandatory measure to ensure the safety of this equipment is a qualified instructing personnel with knowledge verification, in which verification methods, as well as rules for using with him. An important criterion for inspection and safe operation is the use of ancillary equipment such as carriers and extension cords. They also need to be checked once a year and to ensure this is the direct responsibility of the person responsible for the electrical system.

As practice and statistics show, whoever conducts at least a regular high-quality examination is less likely to fall under deadly voltage. Particularly you need to be careful when performing work in wet rooms (basements, bathrooms, etc.) and in the absence of a modern RCD in the power system (residual current device), which quickly responds to breakdowns in the circuit.

Finally, we recommend watching a useful video that shows how to check the quality of an electric tool before buying it:

This technology is used to check and test the power tool. Now you know who conducts the verification work and at what frequency!

It will be helpful to read:

• Safety rules for working with electric tools
• How to use a megohmmeter
• Top Power Tool Manufacturers
• Checking the functionality of the circuit breaker