PTEES: key operating requirements for electrical installations

Author: Viacheslav Yurdyk, quality engineer at LK Energy Group.
Acceptance of equipment at the factory (quality control department) and technical supervision on electrical installation sites.

Short answer

PTEES (Rules of Technical Operation of Consumers' Electrical Installations) governs how an already built installation is to be maintained: who is responsible for it, whose knowledge is tested and how often, which documents must be held, and what is tested and at what intervals. It is binding on staff who operate consumers' electrical installations, control them, regulate consumption regimes or inspect installations, and on enterprises of any form of ownership that design, manufacture, supply, install, commission, test or repair consumers' electrical installations [п. 1.2 розділу І]. A wider statement is given separately: all electrical installations of consumers in service, as well as those being designed, built, reconstructed or upgraded, must comply with legislation, the current PUE and other normative and technical documents [п. 1.3 розділу І]. The version in force dates from 21 February 2017; the document was approved by order No. 258 of the Ministry of Fuel and Energy dated 25.07.2006.

The shortest practical summary: the manager appoints a person responsible for the electrical facilities, that person keeps the documentation and the schedules, and testing is carried out by an accredited laboratory to the scope and intervals set out in annexes 1 and 2 to the Rules [п. 13.1 глави 13 розділу VII]. With those three in place, an inspection by the State Energy Supervision authority passes uneventfully. With none of them, the questions go to the manager personally.

PUE or PTEES: how not to confuse them

This is the most common confusion, and it costs money — people look for a rule in the wrong document.

A telling pair: how many ohms are required is PUE; how often to measure them is PTEES. The Rules themselves are written that way: annex 1 states that the measured value must not exceed the value set by chapter 1.7 of PUE [додаток 1, таблиця 25, п. 3].

Who is responsible: the person responsible for the electrical facilities

This is the central figure of the whole document. By a formal internal order the manager appoints the person responsible for the electrical facilities and the person who deputises during leave or illness [п. 1.4 глави 1 розділу IV].

The order may not be issued until the person has passed a knowledge assessment and has been assigned: - electrical safety group IV — for installations up to 1 kV; - group V — for installations above 1 kV [ibid.].

Requirements for the person [п. 1.5 глави 1 розділу IV]: a relevant electrical or electromechanical education plus experience — at least 1 year for a master's degree and at least 2 years for a bachelor's degree. An exception applies to installations of reliability categories II and III up to 1 kV: an employee with group IV may be appointed with 3 years of experience (vocational education) or 4 years (complete secondary education with special training).

When no responsible person needs to be appointed — this is the most sought-after answer: - the consumer has a single non-sectionalised intake and distribution unit up to 380 V, and the whole installation consists of domestic and lighting appliances in rooms without increased danger, outside explosive and fire-hazardous zones. The manager is then responsible for organising operation — after an induction from the distribution system operator at group II level, given when the supply contract is concluded or renewed [п. 1.8 глави 1 розділу IV]; - a deputy need not be appointed if the installed capacity does not exceed 10 kW [п. 1.7 глави 1 розділу IV].

Two further rules that remove needless argument: - the duties of the responsible person may be performed as a secondary role; where the post of chief power engineer exists, they are normally assigned to that person [п. 1.7 глави 1 розділу IV]; - if setting up an in-house electrical service is not economically justified, the installations are handed over to a specialised organisation under contract [п. 1.6 глави 1 розділу IV].

Knowledge assessment: who and how often

[п. 2.17 глави 2 розділу IV]

Separately — periodic training at a specialised training institution [п. 2.18 тієї ж глави]: the person responsible for the electrical facilities, members of the central board and officers of the operating staff — at least once every three years; all other electrical and electrotechnological staff — once every five years.

🔴 The rule people forget: admitting to work an employee who has not passed the knowledge assessment within the set period is prohibited [п. 2.17 глави 2 розділу IV]. This is not a recommendation but a direct prohibition, and it is what enforcement notices are built on.

Two more basic requirements: age over 18 and a medical examination — on hiring and periodically thereafter [п. 2.4 глави 2 розділу IV].

Which documents must be held

The list from п. 3.1 глави 3 розділу IV — briefly, in plain words, without retelling the whole chapter:

• approved design documentation with all amendments;
• single-line diagrams of primary and secondary connections at all voltages;
• test and measurement records;
• commissioning certificates and as-built diagrams;
• the demarcation record of networks by ownership and operational responsibility with the distribution system operator;
• technical passports of the main electrical equipment, buildings and structures, and certificates for the electrical equipment;
• operating instructions, job descriptions, and occupational-safety and fire-safety instructions for every workplace;
• the supply contract for electricity.

Separately for a shop or a production section [п. 3.2 глави 3 розділу IV] — record cards or registers listing the electrical installations and protective equipment, equipment drawings, drawings of underground cable routes and earthing arrangements referenced to buildings, and general power supply diagrams.

Diagrams are reviewed — that is, checked against reality — and every change made during operation is reflected in the diagrams and drawings [пп. 3.3 глави 3 розділу IV, 3.4 тієї ж глави].

🔑 The practical conclusion. Half of this list is what you receive from the equipment manufacturer and the installation contractor once, at handover. If the passport, the diagram and the test report did not arrive with the switchboard, you will not assemble them later — yet every inspection will ask for them. This is not paperwork for its own sake: without an as-built diagram the next electrician will be working on your site blind.

Testing: what, how often and who is entitled

The scope and the intervals are not at the owner's discretion. They are set by annexes 1 and 2 to the Rules, and these Standards are binding on everyone operating installations up to 150 kV [п. 13.1 глави 13 розділу VII]. For equipment above 150 kV a separate document applies — СОУ-Н ЕЕ 20.302:2007.

Types of check [п. 13.2 тієї ж глави]: - K — during overhaul; - P — during routine repair; - M — between-repair (preventive) tests, without taking the equipment out for repair.

Who is entitled to test [п. 13.5 глави 13 розділу VII]: accredited laboratories, under programmes (procedures) approved by the consumer's manager and in compliance with the Law «On Metrology and Metrological Activity». The results are recorded in test reports or certificates kept together with the equipment passports.

Two rules that save pointless argument: - comparison must be made not only against the limit but against the initial data — that is, against the values in the manufacturer's passport and test reports, or the results after an overhaul [п. 13.3 глави 13 розділу VII]. That is what the passport is kept for throughout the life of the equipment; - measurement of insulation characteristics and withstand voltage testing are carried out at a positive temperature not below 5 °C, unless the Standards specify a higher one [п. 13.6 глави 13 розділу VII]. So «they came to measure in winter in an unheated chamber» is a reason to reschedule the works, not to argue about the result.

Our own case: indoor and outdoor switchgear

There is a dedicated table for switchgear assemblies — annex 1, table 21. Here is an extract covering the most frequent questions:

[додаток 1, таблиця 21 до ПТЕЕС]

Earthing: how often measurement is actually required

This is where market practice has drifted furthest from the rule.

[додаток 1, таблиця 25, пп. 1 і 3]

One figure worth knowing by heart: the transition resistance of a contact joint must not exceed 0.1 Ω in current service [там само, п. 1]. And a separate requirement that is almost never met: the earthing arrangement must also be inspected after a short circuit or lightning strikes [ibid.].

🔴 An honest word about «annual earthing measurements». For an ordinary site the rule is once every 12 years, while each year there is an inspection, not a measurement. PTEES requires annual measurement for especially hazardous conditions and for lifting machinery. If someone is selling you annual measurements for an ordinary workshop, that is a service beyond the rule. It does no harm, but you should understand that you are paying for peace of mind, not for compliance.

Transformers: oil temperature

At rated load the temperature of the top oil layers must not exceed the following (unless the manufacturer's instructions set other values) [п. 4.12 глави 4 розділу VII]:

Related rules from the same chapter: - on transformers with cooling system D the fans must start automatically when the top oil layers reach 55 °C or when rated load is reached, and stop when the oil temperature falls to 45–50 °C, provided the current is below rated [п. 4.13 глави 4 розділу VII]; - the oil level in the conservator of a transformer that is not running must correspond to the ambient temperature; staff are required to monitor the temperature of the top oil layers using thermal signalling devices and thermometers [п. 4.7 глави 4 розділу VII]; - in sealed transformers, if the tank pressure rises above 50 kPa (0.5 kgf/cm²) the load must be reduced [ibid.].

🔴 An important caveat, without which this table is dangerous. 95 °C is the temperature of the oil inside the tank. A pyrometer measures the surface of the enclosure, not the oil and not the air: if it reads 88 °C on the surface of the equipment, the oil inside is hotter still — by how much, a surface reading will not show. The answer comes from the built-in thermal signalling devices and thermometers that staff are required to monitor [п. 4.7 глави 4 розділу VII]. Comparing a surface reading with the oil limit means understating your own conclusion.

How we apply this

• We hand over the passport and the test report with the equipment, because under п. 13.3 глави 13 розділу VII the results of subsequent tests are compared precisely against the manufacturer's initial data. Without that piece of paper, five years later nobody can say whether the insulation has degraded or was like that from the start.
• An as-built diagram is not an extra but part of the delivery: it is on the list of documents the consumer must hold [п. 3.1 глави 3 розділу IV].
• Our own accredited electrical laboratory — this follows п. 13.5 глави 13 розділу VII: testing must be carried out by an accredited laboratory, and the report is kept together with the passport.

Frequently asked questions

Questions about operating your equipment

We manufacture switchgear and go on maintaining it — so PTEES requirements are not theory for us. Send a single-line diagram or a completed data sheet and we will tell you which of these apply to your site.

This material is provided for information only and is neither an offer nor legal advice. We do not publish the full text of the Rules — only quotations with clause numbers; obtain the official text from the source named above.

Fill in the data sheet →

See also

• PUE:2026 — what has changed and how to use it
• Requirements for transformer substations (KTP)
• Earthing under PUE
• Cable laying under PUE
• Selecting a circuit breaker: rating, Icu, discrimination
• Climatic versions U1 and UHL
• Pre-commissioning test standards