18th Ed. Changes

[Sidewinder]

Please use this thread for discussion on the changes in the 18th Edition.







So excluding all the pre-amble up to part 1.

Part 1.

110.1, xxvii has been added,  "onshore units of electrical shore connections for inland navigation vessels"

This covers the connection points for things like river cruise ships, canal boats, or river taxis, marinas are already covered in a section.

Right through the document a.c. & d.c. have been changed to AC & DC for harmonisation with the IEC documents.  I am not going to include any changes related to this.

I'm either going to colour the new bits blue, or explain them, depending on which is the easiest.

So if it's blue it's added, if it's red it's deleted, else it will be explained.

110.1.3, iv has had a standard changed BS EN 61241 has been replaced by BS EN IEC 60079 series, as the 61241 series has been replaced by the 60079 series for equipment in the presence of combustible dust, so we have moved away from EU harmonisation to harmonising with the IEC requirements.

110.2 "Exclusions from scope", has a few changes.

(iv) Equipment on board ships covered by BS 8450, BS EN 60092-507, BS EN ISO 13297 or BS EN ISO 10133

...

(x) Those aspects of lift installations covered by relevant parts of BS 5655 and BS EN 81 and those aspects of escalator or moving walk installations covered by relevant parts of BS 5656 and BS EN 115

113 no changes

114, relationship with statutory regulations, has had the dated reference to ESQCR removed, and changes relating to the re-structuring of the layout.

115 no changes

Ch 12.

120.1 This Standard contains the rules for the design, and erection and verification of electrical installations so as to provide for safety and proper functioning for the intended use.

120.3 This Standard sets out technical requirements to enable intended to ensure that electrical installations to conform to with the fundamental principles of Chapter 13, as follows:

The comment at the end of 120.3 has the wording changed such that it is now required to record any deviations on an EIC, but the requirement is still that deviations shall provide the same level of safety as compliance.

131.2.1 & 131.2.1 have had "(protection against direct contact)" deleted from the end of the line.

Throughout changes noted that occurred in 17th Amd3 have been removed.

132.2, (iii), 4th indent, — prospective short-circuit fault current

132.8 Protective equipment

The characteristics of protective equipment shall be determined with respect to their function, including protection against the effects of:

(i) overcurrent (overload and/or short-circuit)

(ii) earth fault current

132.12 Accessibility of electrical equipment

Electrical equipment shall be arranged so as to afford as may be necessary to provide:

133.1.3 Where equipment to be used is not in accordance with Regulation 133.1.1 or is used outside the scope of its standard, the designer or other person responsible for specifying the installation shall confirm that the equipment provides at least the same degree of safety as that afforded by compliance with the Regulations. Such use is to be noted on the Electrical Installation Certificate shall be recorded on the appropriate electrical certification specified in Part 6.

Note the change in wording in 133.1.3, this is strengthened, it is "shall", which in legal and standards parlance is you must do, I realise that 7671 is not law, but if you are going to claim compliance with HASAWA & EAWR by following BS 7671, then, you must, do the shall clauses.

134.1.1 Good workmanship by one or more skilled or instructed persons and proper materials shall be used in the erection of the electrical installation. The installation of electrical equipment shall take account of manufacturers' instructions.

134.2 has been changed to reflect I&T being moved to Ch 64 & 65.

That's part 1 finished.

Part 2, definitions

Any definitions that were removed by previous versions have been removed.

Also the following changes:

Back-up protection.

Protection which is intended to operate when a system fault is not cleared, or abnormal condition not detected, in the required time because of failure or inability of other protection to operate or failure of the appropriate circuit-breaker(s) to trip.Protection of a device by overcurrent co-ordination between that device and an overcurrent protective device (OCPD) in series with it, generally but not necessarily on the supply side. This prevents any excessive stress on the electrical device.

Discrimination.

Ability of a protective device to operate in preference to another protective device in series.(see Selectivity)

Follow-current interrupting rating, {534}Ifi.

The level of pProspective short-circuit current that an SPD is able to interrupt without back-up protectionoperation of the OCPD

Isolation.

A functionFunction intended to cut offmake dead for reasons of safety the supply from all, or a discrete section, of the electrical installation by separating the electrical installation, or section thereof, from every source of electrical energy.

Monitoring.

Observation of the operation of a system or part of a system to verify correct functioning or detect incorrect functioning by measuring system variables and comparing the measured values with specified values.

Protective multiple earthing (PME).

An earthing arrangement, found in TN-C-S systems, in which the supply neutral conductor is used to connect the earthing conductor of an installation with Earth, in accordance with the Electricity Safety, Quality and Continuity Regulations (ESQCR) 2002 (see also Figure 3.9).

Residual current device (RCD).

A mMechanical switching device designed to make, carry and break currents under normal service conditions andor association of devices intended to cause the opening of the contacts when the residual current attains a given value under specified conditions.

Selectivity.

(see Discrimination).Co-ordination of the operating characteristics of two or more protective devices such that, on the incidence of an overcurrent or residual current within stated limits, the device intended to operate within these limits does so, while the other(s) does (do) not.

Switch.

A mechanical device capable of making, carrying and breaking current under normal circuit conditions, which may include specified operating overload conditions, and also of carrying for a specified time currents under specified abnormal circuit conditions such as those of short-circuit. It may also be capable of making, but not breaking, short-circuit currents.

 

[Sidewinder]

Part 3

Chapter 30

Deleted from the bottom of 301.1:

These characteristics shall be taken into account in the choice of methods of protection for safety (see Chapters 41 to 44) and the selection and erection of equipment (Chapters 51 to 56).

312.2.1.1

Deleted from after Figure 3.9

The usual form of a TN-C-S system is as shown, where the supply is TN-C and the arrangement in the installations is TN-S.

314.1

(ii)  facilitate safe inspection, testing and maintenance (see also Chapter 46 and Section 537)

314.3

The number of final circuits required, and the number of points supplied by any final circuit, shall be such as to facilitate compliance with the requirements of Chapter 43 for overcurrent protection, Chapter 46 and Section 537 for isolation and switching and Chapter 52 as regards current-carrying capacities of conductors.

Ch 32, 33 & 34 nothing worth note.

Ch 35

351 General

NOTE 2: Examples of safety services are: emergency escape lighting, fire detection and fire alarm systems, installations for fire pumps, firefighters rescue service lifts, smoke and heat extraction equipment.

Ch 36

361.1

(ii)  Selection of the protective device in order to achieve discriminationselectivity

That's the end of Part 3.

 

[Sidewinder]

Part 4

Ch 41

410

2nd paragraph

The fundamental rule of protection against electric shock, according to BS EN 61140, is that hazardous-live-parts shall not be accessible and accessible conductive parts shall not be hazardous-live, either both under normal conditions and under in use without a fault or in single fault conditions.

4th paragraph

In BS 7671:2001:

(i) protection in use without a fault (now designated basic protection) was referred to as protection against direct contact, and

(ii) protection under fault conditions (now designated fault protection) was referred to as protection against indirect contact.

410.3

Some changes to punctuation and case related to AC & DC.

410.3.3, change in case in indents for editorial correctness

410.3.4 For special installations or locations, the additional particular protective measures specified in the corresponding section of Part 7 shall be applied.

410.3.5 The protective measures specified in Section 417, i.e. the use of obstacles and placing out of reach, shall only be used only in installations where access is restricted to:

410.3.6

(iii) electrical separation for the supply to of more than one item of current-using equipment

There are lots of editorial changes relating to punctuation, and capitalisation, plurals etc that I am not going to include because the intent of the clause is still the same, and it will increase the number of changes a LOT!

Such as the indents in 410.3.9

411.1 para 3

Where specified, the requirements for additional protection shall be is provided by an RCD with rated residual operating current not exceeding 30 mA, in accordance with having the characteristics specified in Regulation 415.1.1.

Enough for now.

 

[Sidewinder]

Carrying on, there are quite a few minor grammatical changes where the wording of the regulation has changed slightly in detail, such as "Distribution Network Operator" has been replaced with "Distributor", or a regulation has changed from referring to a plural and now refers to the singular.  I have not included these.

I have also spotted a few errors in the official IET document that I am working from, which is in the public domain, but is a subscription service, so if things have been missed, are missed or are incorrect I can only apologise that I have missed them, but, I can only work with the information that I have available.

411.2 Requirements for basic protection

All electrical equipment shall comply with one of the provisions for basic protection (protection against direct contact) described in Section 416(basic insulation; barriers or enclosures) or, where appropriate, Section 417 (obstacles; placing out of reach).

411.3.1.1

4th paragraph deleted

Each circuit shall have available a protective conductor connected to the relevant earthing terminal.

411.3.1.2

2nd paragraph as been added

Metallic pipes entering the building having an insulating section at their point of entry need not be connected to the protective equipotential bonding.

411.3.2.2 The m Maximum disconnection times stated in Table 41.1 shall be applied to final circuits with a rated current not exceeding: 32 A.

(i) 63 A with one or more socket-outlets, and

(ii) 32 A supplying only fixed connected current-using equipment.

Table 4.1

No longer has seconds against the columns it now just shows (s)

In the rows beneath the figures:

U0 is the nominal AC rms or ripple-free DC line voltage to Earth.

There is also an additional note to the table, so the original note has been renumbered as Note 1

NOTE 2: Where disconnection is provided by an RCD, see Note 2 to Regulation 411.4.4, Note 1 to Regulation 411.5.3 and Note 4 to Regulation 411.6.5.

411.3.2.5 has been re-worded and is now:

411.3.2.5 Where it is not feasible for an overcurrent protective device to interrupt the supply in accordance with Regulation 411.3.2 or the use of an RCD for this purpose is not appropriate, see Section 419. However, disconnection may be required for reasons other than protection against electric shock.

413.2.6 has been deleted.

411.3.3 is now:

411.3.3 Additional protection requirements for socket-outlets and for the supply of mobile equipment for use outdoors

In AC systems, additional protection by means of an RCD with a rated residual operating current not exceeding 30 mA in accordance with Regulation 415.1 shall be provided for:

(i) socket-outlets with a rated current not exceeding 20 32A, and

(ii) mobile equipment with a rated current rating not exceeding 32A for use outdoors.

An exception to (i) is permitted where, other than for an installation in a dwelling, a documented risk assessment determines that RCD protection is not necessary.

An exception to (i) is permitted:

(a) where, other than for an installation in a dwelling, a documented risk assessment determines that the RCD protection is not necessary, or

(b) for a specific labelled or otherwise suitably identified socket-outlet provided for connection of a particular item of equipment.

NOTE 1: See also Regulations 314.1(iv) and 531.2.4 concerning the avoidance of unwanted tripping.

NOTE 2: The requirements of Regulation 411.3.3 do not apply to FELV systems according to Regulation 411.7 or reduced low voltage systems according to Regulation 411.8.

NOTE 3: See Appendix 2, item 10 in respect of risk assessment.

 

[Sidewinder]

OK, an update, I am working through the changes.  The document I was using above, did not highlight the full changes, so they may be incorrect.

A friend of mine has done some very good update videos on YouTube here:

https://www.youtube.com/playlist?list=PLg1OV4f2xHzVZMPyo_A8xd7s2jzd8WhP3

I have seen a few questions about socket outlets and RCD's, I'll try to illustrate the new requirements.

One specific question is regarding the requirement for RCD's on socket outlets.

This relates to Chapter 41.

The summary headline changes from the introduction related to this are as follows:

The maximum disconnection times stated in Table 41.1 now apply to final circuits rated up to 63 A with one or more socket-outlets and final circuits rated up to 32 A supplying only fixed connected current-using equipment (Regulation 411.3.2.2).

Regulation 411.3.3 has been revised and now applies to socket-outlets with a rated current not exceeding 32 A. There is an exception to omit RCD protection where, other than for a dwelling, a documented risk assessment determines that RCD protection is not necessary.

So, looking at these regulations in more detail.

17thAmd3:

411.3.2.2 The maximum disconnection time stated in Table 41.1 shall be applied to final circuits not exceeding 32 A.

18th:

411.3.2.2 Maximum disconnection times stated in Table 41.1 shall be applied to final circuits with a rated current not exceeding:

(i) 63 A with one or more socket-outlets, and

(ii) 32 A supplying only fixed connected current-using equipment.

Table 41.1 has one change in it's body:

120 V ˂ U0 ≤ 230 V DC, Disconnection time int he 17th was 5s, it is now in the 18th 1s.

There are some changes to the notes in table 41.1 also.

17th:

Where, in a TT system, disconnection is achieved by an overcurrent protective device and protective equipotential bonding is connected to all the extraneous-conductive-parts within the installation in accordance with Regulation 411.3.1.2, the maximum disconnection times applicable to a TN system may be used.

U0 is the nominal a.c. rms or d.c. line voltage to Earth.

Where compliance with this regulation is provided by an RCD, the disconnection times in accordance with Table 41.1 relate to prospective residual fault currents significantly higher than the rated residual operating current of the RCD.

NOTE : Disconnection is not required for protection against electric shock but may be required for other reasons, such as protection against thermal effects.

18th:

Where in TT systemst he disconnection is achieved by an overcurrent protective device and the protective equipotential bonding is connected with all extraneous-conductive-parts within the installation in accordance with Regulation 411.3.1.2, the maximum disconnection times applicable to TN systems may be used.

U0 nominal AC rms or ripple-free DC line voltage to Earth.

Where compliance with this regulation is provided by an RCD, the disconnection times in accordance with Table 41.1 relate to prospective residual fault currents significantly higher than the rated residual operating current of the RCD.

NOTE 1: Disconnection is not required for protection against electric shock but may be required for other reasons, such as protection against thermal effects.

NOTE 2: Where disconnection is provided by an RCD, see Note 2 to Regulation 411.4.4, Note 1 to Regulation 411.5.3 and Note 4 to Regulation 411.6.5.

OK on to 411.3.3

17th:

411.3.3 Additional protection

In a.c. systems, additional protection by means of an RCD in accordance with Regulation 415.1 shall be provided for:

     (i) socket-outlets with a rated current not exceeding 20 A, and

     (ii) mobile equipment with a current rating not exceeding 32 A for use outdoors.

An exception to (i) is permitted:

(a) where, other than for an installation in a dwelling, a documented risk assessment determines that the RCD protection is not necessary, or

(b) for a specific labelled or otherwise suitably identified socket-outlet provided for connection of a particular item of equipment.

NOTE 1: See also Regulations 314.1(iv) and 531.2.4 concerning the avoidance of unwanted tripping.

NOTE 2: The requirements of Regulation 411.3.3 do not apply to FELV systems according to Regulation 411.7 or reduced low voltage systems according to Regulation 411.8.

NOTE 3: See Appendix 2, item 10 in respect of risk assessment.

18th:

411.3.3 Additional requirements for socket-outlets and for the supply of mobile equipment for use outdoors

In AC systems, additional protection by means of an RCD with a rated residual operating current not exceeding 30 mA shall be provided for:

     (i) socket-outlets with a rated current not exceeding 32A, and

     (ii) mobile equipment with a rated current not exceeding 32A for use outdoors.

An exception to (i) is permitted where, other than for an installation in a dwelling, a documented risk assessment determines that RCD protection is not necessary.

The requirements of Regulation 411.3.3 do not apply to FELV systems according to Regulation 411.7 or reduced low voltage systems according to Regulation 411.8.

NOTE 1: See also Regulations 314.1(iv) and 531.3.2 concerning the avoidance of unwanted tripping.

NOTE 2: See Appendix 2, item 11 in respect of risk assessment.

NOTE 3: A lighting distribution unit complying with BS 5733, luminaire track system, installation coupler, LSC or DCL is not regarded as a socket-outlet for the purposes of this regulation.

OK, so we can see that the extension for RCD's on socket outlets has been extended up to 32A, thus including 32A single & 3ph sockets up to and including 32A, so that's all domestic sockets, i.e. BS 1363 13A, 16 A blue, single phase 230V, & red 3 ph (TPN & TPNE) 400V, IEC 60309 ("commando") socket outlets in all situations, domestic, commercial and industrial.

However, it, does, allow the exclusion except in a dwelling that it can be omitted by provision of a suitable RA.

Now, the RA is not down to the installer, it cannot be, unless the installer is the end user, i.e. in house installers, when the risk is on their employer, thus the end user.

The designer can have an input into the RA, but, it still remains the responsibility of the end user to undertake, and abide by the RA.  The designer can advise the end user of the risks, and any mitigation that is required, or could be necessary.  The RA must be the ultimate responsibility of the end user, and owned and reviewed by the end user at suitable intervals.

So ultimately, in any commercial or industrial premises, it is acceptable to omit RCD protection from socket outlets as long as the design specifies this, & the end user understands fully the risks, accepts this risk, and undertakes a documented risk assessment, which, preferably needs to be appended to the EIC.  However, any statement from the end user which states that RCD protection is not required, and they take the responsibility for the supervision of this danger would be acceptable.

It would need to be noted as a deviation, but, there is nothing wrong with this.