Report on the results of measuring the insulation resistance of electrical wiring

Why are measurements taken?

This control action is a mandatory part of a set of measures for maintaining the electrical network.

The main purpose of measuring insulation resistance is to monitor the operation of power lines and timely prevent any malfunctions and breakdowns.

Damaged electrical wiring can lead to harm to human health (including electric shock and serious burns) and emergency situations. If we are talking about manufacturing companies, then due to power outages caused by flaws, breaks, damage to electrical cables and other electrical equipment, disruptions in production processes may occur and, as a result, large financial losses.

Based on this, all enterprises are interested in ensuring that electrical communications maintenance is carried out efficiently and in a timely manner. Based on the results of each check of the condition of electrical networks, special reporting documents are generated, including acts of measuring insulation resistance.

Insulation resistance measurements, grounding resistance measurements.

Measuring the insulation resistance of wires is the main type of checking the condition of electrical wiring in premises. Measurements are carried out using certified measuring instruments. Insulation resistance measurements are carried out by specially trained people. Methods of measurement work are agreed upon by the controlling organization - Rostechnadzor.

The electrical engineering laboratory will perform the entire range of electrical measuring and commissioning work in electrical installations, electrical equipment and electrical networks . The mobile electrical laboratory measures and tests electrical equipment:

• Insulation resistance measurement.
• Ground resistance measurements.
• Checking the phase-zero loop.
• Checking metal connections.
• RCD check.

Electrical measuring work is carried out for the purposes of fire safety, protection against electric shock, checking the correctness of electrical installation work and compliance of electrical installation work with design and technical documentation.

Measuring work, or otherwise known as commissioning work, is usually carried out after the completion of electrical installation work and is necessary to check the quality of operation of power circuits and lighting lines. The result of electrical measurements is a technical report, sealed by a laboratory registered with Rostekhnadzor. Periodic electrical measurements are carried out in accordance with the requirements of fire supervision and energy supervision.

Attention budgetary organizations - you can request a commercial proposal for a tender for electrical measurements in Yandex chat. We will send you a commercial offer by email.

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In order to make an estimate for measuring insulation resistance , determine the number of lines by looking at the number of lines in a single-line diagram. Typically the single line diagram is located on the electrical panel cover.

Measuring insulation resistance begins with viewing a single-line diagram of the electrical panel.

If there is no single-line diagram, then it is necessary to count the number of lines by the number of circuit breakers in the electrical panel.

Measuring wire insulation resistance

Electrical measurements are carried out in administrative buildings, residential buildings, shopping malls, stores, and industrial enterprises once every 3 years.

In rooms with high humidity - kitchens, laundry - electrical wiring tests are carried out once a year.

Cost of one resistance measurement:

• Insulation resistance measurement - 100 rubles per measurement
• Measurement of ground loop resistance - 400 rubles
• RCD check - 200 rubles per device
• Checking metal connections - 100 rubles for 1 point, 3-wire socket.

The cost of measurement does not include overhead, transportation costs, surcharges for urgent work (within 2 hours).

We provide free on electrical connection issues.

We work in the Saratov, Volgograd, Penza, and Moscow regions.

What is meant by "isolation"

Any electrical cable must be specially insulated. The insulating coating allows you to separate the wires through which current flows, as well as disconnect these wires from the ground.

In order to assess how well such insulation “works”, its resistance is measured - their results are the main value in the work of electrical specialists.

The first measurement is carried out at the cable manufacturer, then during installation and subsequently during the entire period of use of the cable product. This is due to the fact that insulation is influenced by factors such as weather, period of its use, quantity, frequency of damage on the line, etc.

Who takes the measurements

To carry out measurements, electricians and other specialists who have permission to work with electrical communications and electrical equipment are involved.

If we are talking about periodic inspections in an organization, then a special commission is created to monitor electrical insulation, which includes an employee of the enterprise and a specialist from the installation or maintenance company.

The commission must include at least two people, but if necessary, its composition can be expanded to include outside experts.

The task of the commission is to check the condition of the cable and measure the resistance of the insulating coating, and then enter all the indicators into the report.

Features of document preparation

If you are faced with the task of creating an insulation resistance measurement report, and you have never made such a document before, we will give you some recommendations. Look at the ready-made example - based on it, you can easily design your own form.

Before moving on to the details, let’s outline some of the details that are typical for all papers of this kind.

1. Firstly, any act today can be written in free form. However, if there is a form within the organization, it is better to make a document according to its type, since it is most likely designed to meet all needs and contains the necessary columns, rows and tables.
2. Secondly, the act can be drawn up manually or typed on a computer. In the second case, the completed form must be printed. This is necessary so that the persons participating in the control activities can put their signatures on the document - without these autographs it will not be considered valid. If an enterprise uses stamps to endorse its documentation, a seal impression should be included in the act.
3. Thirdly, the act must be made in at least two identical copies - one for each of the parties involved in the measurements. In addition, if necessary, additional copies can be made, also certified properly.

After the act is formed and signed, it is subject to mandatory storage. The storage period is determined either by current legislation or by internal regulations of the enterprise (but not less than three years).

Sample insulation resistance measurement report

At the beginning of the form its name, date and place of compilation are written. Then the following information is given:

• data about the object at which measurements are taken;
• information about the device with which they are carried out;
• operating voltage in the electrical network;
• information about the commission whose members carry out the measurements (here you must indicate their place of work, position and full name).

Below is a plate in which the readings of the measuring device are entered and the conclusion of the inspectors is given.

The table given in the example is not strictly mandatory - it can be supplemented with information, depending on the needs and tasks facing those who make the measurements.

If any malfunctions are identified, members of the commission must indicate their presence, as well as give advice on how to eliminate them. If any additional documents are attached to the act (photo and video evidence of breakdowns, cable breaks, instrument readings, etc.), this must also be reflected in the document.

At the end, the form is signed by the commission members, and the autographs are deciphered.

Source

Insulation resistance measurement report, sample filling

Download the document in word format. Source - RD 78.145-93 “Manual for the governing document of systems and complexes of security, fire and security-fire alarm systems, rules for production and acceptance of work.”

ACT

measuring the insulation resistance of electrical wiring

City _______________ “_____” ____________ 20___

An object ______________________________________________________________ _

Commission consisting of representatives:

(name of organization, position, surname, initials)

Representative of the person carrying out the construction_________________________________

(name of organization, position, surname, initials)

Person exercising construction control_______________________________________________

(name of organization, position, surname, initials)

Representative of the installation organization_______________________________________________

(name of organization, position, surname, initials)

carried out measurements of the insulation resistance of electrical wiring. Control device data:

Marking of wire (cable) according to the drawing

Brand of wire (cable)

Number and cross-section of cores sq. mm

Insulation resistance, MOhm

The insulation resistance of the listed electrical wiring meets the technical requirements.

Representative of the developer/customer__________ ______________ ______________________

___________________________________________ ______________ ______________________

(position, surname, initials, signature)

Representative of the person carrying out the construction_ ____________ ___________

_____________________________________________ ______________ ___________

(position, surname, initials, signature)

Person exercising construction control_______ _________ ______________

______________________________________________________ ___ _ _____________

(position, surname, initials, signature)

Representative of the installation organization_________ ______________ _______________

_____________________________________________ ______________ ____________

Source

Report on the results of measuring the insulation resistance of electrical wiring

Download the document in word format. Source - RD 78.145-93 “Manual for the governing document of systems and complexes of security, fire and security-fire alarm systems, rules for production and acceptance of work.”

ACT

measuring the insulation resistance of electrical wiring

City _______________ “_____” ____________ 20___

An object ______________________________________________________________ _

Commission consisting of representatives:

(name of organization, position, surname, initials)

Representative of the person carrying out the construction_________________________________

(name of organization, position, surname, initials)

Person exercising construction control_______________________________________________

(name of organization, position, surname, initials)

Representative of the installation organization_______________________________________________

(name of organization, position, surname, initials)

carried out measurements of the insulation resistance of electrical wiring. Control device data:

Marking of wire (cable) according to the drawing

Brand of wire (cable)

Number and cross-section of cores sq. mm

Insulation resistance, MOhm

The insulation resistance of the listed electrical wiring meets the technical requirements.

Representative of the developer/customer__________ ______________ ______________________

___________________________________________ ______________ ______________________

(position, surname, initials, signature)

Representative of the person carrying out the construction_ ____________ ___________

_____________________________________________ ______________ ___________

(position, surname, initials, signature)

Person exercising construction control_______ _________ ______________

______________________________________________________ ___ _ _____________

(position, surname, initials, signature)

Representative of the installation organization_________ ______________ _______________

_____________________________________________ ______________ ____________

Source

Recommended

ACT

measuring the insulation resistance of electrical wiring

City _______________ “_____” ____________ 20___

An object _______________________________________________________________

Name

Project N_______________________________________________________________

Commission consisting of representatives:

Representative of the developer/customer_______________________________________________

_______________________________________________________________________________

(name of organization, position, surname, initials)

Representative of the person carrying out the construction_________________________________

_______________________________________________________________________________

(name of organization, position, surname, initials)

Person exercising construction control_______________________________________________

_______________________________________________________________________________

(name of organization, position, surname, initials)

Representative of the installation organization_______________________________________________

_______________________________________________________________________________

(name of organization, position, surname, initials)

carried out measurements of the insulation resistance of electrical wiring.
Control device data: Device name

Test data

Commission conclusion:

The insulation resistance of the listed electrical wiring meets the technical requirements.

Representative of the developer/customer_______________________________________________

_______________________________________________________________________________

(position, surname, initials, signature)

Representative of the person carrying out the construction________________________

______________________________________________________________________

(position, surname, initials, signature)

Person exercising construction control______________________________

_______________________________________________________________________

(position, surname, initials, signature)

Representative of the installation organization_______________________________________________

_______________________________________________________________________

(position, surname, initials, signature)

Occupational health and safety at school

The organization must monitor the operation of wires and cables. Upon completion of measurements, a Certificate of Measurement of Insulation Resistance of Electrical Wirings , since measurements of insulation resistance will allow timely identification of faults and prevention of breakdowns. Damaged electrical wiring can lead to accidents, fire and electric shock. Therefore, timely diagnostics of electrical wiring and elimination of defects are a security measure in the organization.

All electrical cables and wires must be insulated. During measurements, a report or protocol for measuring the insulation resistance of electrical wiring (wires and cables) can be drawn up. Measurements are carried out by an electrician and specialists who have permission to work with electrical communications and electrical equipment. For periodic inspections, the organization creates a commission to monitor insulation, including an employee of the organization and a specialist from the installation (maintenance) company. The commission is obliged to measure the insulation resistance of wires and cables and draw up a report on measuring the insulation resistance of electrical wiring. A sample act is presented on this page.

What is included in the form for measuring the insulation resistance of electrical wiring?

The most important element of the document is a table in which information regarding the results obtained is entered. It is worth noting that the form of the act of measuring the insulation resistance of electrical wiring contains information regarding the value of the indicator between the conductors, as well as between the conductor and the ground, which allows you to most fully establish the safety of operation of the system or the lack thereof.

Also, the act of measuring the insulation resistance of electrical wiring must indicate in relation to which wires the measurement was carried out: this is important both for the inspectors and for the owner of the premises.

Do not forget that tests must be carried out using standardized control devices that have passed state verification and are included in the register of acceptable equipment. To confirm that the measurements were carried out with precisely such devices, the act of measuring the insulation resistance of the electrical network must indicate their brand, model, and scale type. Mandatory details also include information about the organization and responsible persons who performed the measurement.

ACT for measuring the insulation resistance of electrical wiring

Object__________________________________________________________________________ ________________________________________________________________________________ Project No. ________________________________________________________________

A commission consisting of representatives of: customer ________________________________________________________________ _________________________________________________________________________ _________________________________________________________________________ installation organization ___________________________________________________ measured the insulation resistance of electrical wiring.

Characteristics of control devices:

Commission conclusion: the insulation resistance of the listed electrical wiring meets the technical requirements.

Why do you need a certificate of measuring the insulation resistance of the electrical network?

If you need to undergo a comprehensive inspection of the electrical supply of an apartment or other facility, you cannot do without analyzing the condition of the protective sheath of the wire. To do this, it is worth using the services of a specialized electrical laboratory: its main advantage is the ability to prepare official documents.

In particular, specialists have a special form for measuring the insulation resistance of electrical wiring, which must be filled out at the time of receiving the results of quantitative and qualitative research. The act, as well as the protocol attached to it, will be useful to you when carrying out approvals, as well as obtaining permits regarding the start and continuation of operation of the installation.

Example of a technical report

Forward

Protocol for measuring insulation resistance. Sample for single phase circuit

The protocol for measuring insulation resistance in a single-phase network is filled out by electrical laboratories and other organizations whose activities are related to electrical installation work. It is necessary for drawing up an insulation resistance measurement report and is the basis for filling out its data.

This document is also part of the technical report on electrical measurements. Electrical engineering companies of various types can thus sum up the results of their work and report to customers or higher authorities on the conduct of relevant research.

Report and protocol for measuring insulation resistance

The main part of complex electrical measuring work is the measurement of insulation resistance. ᚠᛟᛋ It is carried out in accordance with the requirements of the Electrical Installation Rules (PUE).

Carrying out insulation measurements is a prerequisite for the operation of electrical installations. The bodies of Rostechnadzor and Pozhnadzor may at any time request a protocol for measuring insulation resistance. There are also cases when this document is requested by the landlord from the tenant (if the former rents not only premises, but also an electrical installation - an electrical panel and electrical equipment that receives power from it). The protocol is drawn up by the electrical measuring laboratory and is included in the technical report for testing the installations.

The essence of checking the insulation resistance is to analyze the condition of the cables and wires that form the electrical network. The megohmmeter directs the test voltage through the cable cores. After this, readings are taken on the resistance between each core relative to each other. This allows you to assess the current state of the insulating sheath of wires and cables.

As a rule, for new cables and wires the insulation resistance value exceeds 1000 MΩ. The minimum resistance value for cables and wires is 500 kOhm. If the value obtained as a result of measurements is at the lower limit, this means that the cable needs to be replaced. Operating cables and wires with resistance close to the lower limit is acceptable, but poses a serious danger.

Different types of measurements

Protocols for measuring the insulation resistance of single-phase and three-phase circuits look different.

For a single-phase circuit, three measurements are sufficient; for a three-phase circuit there should be ten (if it is five-wire).

For this reason, documents for different circuits have different appearances. Although they may be identical in appearance, the “filling” of the wire (and devices corresponding to the voltage being conducted, for example, RCDs) affects what kind of paper will be filled.

You should also pay attention to the differences in the requirements for resistance and voltage in conductors with different cross-sections of conductors.

Components of a protocol

The document is filled out on one side of the sheet. In the upper part on the left is the full name of the measurement contractor with address data. Information in the same format about the customer is also required. Below in the form is the name of the agreement. Next to it is the document number entered in the registers. The date of signature is also indicated here.

For the convenience of providing information, specific data on cables and their conductivity, according to measurements, are presented in the form of two tables. The first has the following columns:

• Serial number.
• The name of the accession.
• Cable brand, number of cores, their cross-section. If possible, it is necessary to indicate whether there is insulation on the cable cores and what material the conductor is made of (the default is copper, but there are also options for conductors with an outer copper sheath and an internal aluminum content). If a wire is examined for resistance, then you also need to indicate how many wires it has and whether it is insulated.
• Insulation resistance in L–N core.
• Insulation resistance in L–PE.
• Insulation resistance in N–PE.
• Conclusion on compliance. Here we mean meeting the requirements of PUE clause 1.8.37 (7th ed.) for electrical wiring and PUE clause 1.8.40 (7th ed.) for cable lines.

The second describes the equipment used for measurements and consists of columns with information such as:

• serial number;
• device name;
• type;
• factory number;
• range of available measurements;
• basic error;
• certificate number;
• date of last check;
• date of the next device check.

Both tables can contain one or several rows. Measurements cannot be carried out without equipment at all, so filling out the second table if the document exists is mandatory. At the very end of the tables, the regulatory document must be indicated (GOST, PUE, SaNPiN, PTEEP, instructions RD and SO., etc.), for compliance with which the insulation of a specific single-phase circuit was tested.

Based on these tables and the information found in the documents, a conclusion must be made: whether the conductor insulation meets the stated requirements or not. It is formulated in writing, in a special column “Conclusion”. The form provides only one line for this, since one word or sentence “complies” or “does not correspond” will be enough.

Deadlines

The time it takes to compile and complete the report will depend on the type and complexity of the measurements being taken. Another important factor is the volume of measurement work. In the simplest cases, the protocol for measuring insulation resistance in a single-phase circuit falls into the hands of the customer the next day after the equipment has been tested. And the maximum period is set by mutual agreement of the parties and is usually sealed by an Agreement for carrying out work on electrical measurements and testing of an electrical installation.

Source