cornishsparks

Has any one had chance to see what the 17th regs have in store for us.
Seems like all circuits that are enclosed in walls ran horizontally and vertically in the accepted zones will have to be RCD protected if they are not in steel conduit. But single RCD control still not advised. will be lots of expensive installations with RCBO single MCB'S.
Also heard socket outlets allowed in bathrooms in zone 3, seems like madness to me, ayone got any comments.
thanks
Cornishsparks

Andy in ATL

Can one of you Brits give us Yanks a run down on these "zones" you speak of when you get a chance?

frank

Andy- Just for you.






Zone 0 The interior of the bath or shower which can hold water. Zone 1 The area directly above zone 0 limited vertically to 2.25m above the bottom of the bath or shower. Zone 2 The area beyond zones 0 and 1, 0.6m horizontally and up to 2.25m vertically. Zone 2 also included any window with a sill next to the bath. Zone 3 The area beyond zones 2, 2.4m horizontally and up to 2.25m vertically. Note:

• Where ceiling heights exceed 2.25m, the zones are effectively up to 3m - beyond 3m, the walls are 'out of scope'.
• Basins are not covered, however they are usually considered to be Zone 2.
• Providing that the space under the bath cannot be accessed without using tools (i.e. screwdriver etc), that space is considered to be 'out of scope'.

Electrical equipment may be identified as having a certain level of mechanical and moisture protection, these are quoted as 'Ingress Protection' (or IP) numbers - such as 'IPXY', where X and Y are numbers, the X showing the level of mechanical protection and Y showing the level of moisture protection - in both cases, the higher the number, the better the protection. If a piece of equipment does not have an IP number, it must not be used in zones 0, 1 or 2 (or elsewhere having a wet/damp environment).
Typical electrical items which are marked with IP numbers include:

• Extractor fans
• Lighting
• Heaters
• Electrical shower units
• Shower pumps

Shaver power points are not IP rated, however, if they comply with BS EN 60742 Chapter 2, Section 1, they can be located in zone 2 (or beyond) providing they are unlikely be be the subject of direct spray from any shower.
As well as IP numbers, items may be classed as PELV or SELV.

• Protective Extra-Low Voltage (PELV) - As the name suggests, the item uses low voltage but it is connected to earth.
• Safety Extra-Low Voltage (SELV) - Again a low voltage system but the output is isolated from the input.

Standard electrical wall fittings (such as wall sockets, flexible cord outlets and fused switches etc) are not IP rated so cannot be installed within zones 0, 1 or 2. No standard socket outlets are allowed anywhere in the bathroom.

Use of Equipment
Any electrical item approved for use in a zone may be used in another zone with a higher number, but not in a lower number zone.
Zone 0 Requires electrical products to low voltage (max. 12 volts) and be IPX7 (the mechanical protection is unimportant). Zone 1 Requires electrical products to be IPX4 or better, or SELV with the transformer located in zone 3 or beyond. If the fitting is 240v, a 30mA RCD must be used to protect the circuit. Zone 2 Requires electrical products to be IPX4 or better, or SELV with the transformer located in zone 3 or beyond. Zone 3 The regulations do not specify any IP number for zone 3, however reference should be made to the manufacturers data in case it indicates any exclusion. Portable electrical equipment is not permitted other than that using a SELV or shaver unit. Beyond zone 3 When the size of bathroom extends beyond zone 3, portable equipment is allowed, however they should be positioned such that that their flex length does not enable them to be used in zone 3. Frank

chrisb271

This is the letter i got from The NIE EIC regards the 17th edition.



What are the potential changes in BS7671: 2008?
The 17th Edition of the Wiring Regulations is published on 1st January 2008 and expected to come into full effect after a six month transition period. NICEIC technical expert Steve Hesketh examines the likely changes.
Some electrical contractors may ask why we need another Edition of the Wiring Regulations. This is a fair question, considering the amount of reprints and amendments over the years. You might think that, to date, there have only been three editions of the Wiring Regulations since the 14th Edition was published in 1966.
However, consider this: Although the 14th Edition was issued in 1966, it was reprinted in 1968, 1969, 1970, 1972, 1973, 1974 and 1976. The 15th Edition was issued in 1981 but reprinted in 1983, 1984, 1986, 1987 and 1988. Finally, the 16th Edition was issued in 1991, but reprinted in 1992, 1994, 1997 and 2004 too!
A combination of new technologies, products and continuing harmonization mean that the Wiring Regulations have to incorporate changes such as these; and we can expect no let up in this progress as time goes by.
The following information outlines some of the more significant changes expected, based on the draft issued for public comment. It may be worth having a copy of the 16th Edition handy when reading this, so you can see clearly aspects of the proposed changes.
This revised standard will include the changes necessary to maintain technical alignment with European Harmonization Documents. It’s important to note that all of the regulations have been renumbered to align with the International Electrotechnical Commission’s (IEC) numbering system. This has also involved partial restructuring of the standard with Part 6 becoming Part 7 and vice-versa.
But let’s start at Part 1; additional regulations relate to the requirements to protect against voltage disturbances and to implement measures against electromagnetic influences. Part 2, ‘Definitions’, includes a number of significant new and amended definitions. New requirements relating to safety services and continuity of service considered necessary during the intended life of the installation are addressed in Part 3.
There are several significant changes to Part 4, ‘Protection for safety’. Whilst the fundamental principles of shock protection remain the same, the changes to definitions such as basic protection for direct contact and fault protection for indirect contact, along with a partial restructuring of Part 4 (such as Part 41 now includes parts of Chapter 47) means that those readers familiar with the 16th Edition will need to spend time getting familiar with the revised Part 4. The provision of supplementary protection by RCD now comes under the heading additional protection and the requirements to provide RCDs have been extended.
The Tables in Chapter 41 for earth fault loop impedances are based on a nominal voltage of 230 V (not 240 V), hence the values are slightly changed. The Chapter also includes a new Table 41.5 giving maximum values of earth fault loop impedance for RCDs.
Chapter 42, Protection against thermal effects now includes the requirements for where particular risks of fire exist (previously in Section 482).Chapter 43, Protection against overcurrent now includes the requirements previously given in Section 473.
Protection against voltage disturbances (Chapter 44) has now been expanded including a new Section 442, ‘Protection of low voltage installations against temporary overvoltages due to earth faults in the high voltage system and due to faults in the low voltage system’.
In Part 5, ‘Selection and erection of wiring systems’ will now include requirements for busbar trunking systems and powertrack systems. The requirements relating to cables concealed in a wall or partition have been altered so that protection by a 30mA RCD is an additional requirement for ‘unprotected’ cables (e.g. twin and earth cables installed in a chase less than 50mm deep); it must be emphasised that such cables must still be installed in ‘safe’ zones. Previously, the requirements for protection, isolation, switching, control and monitoring were covered in several different sections of BS 7671. In the 17th Edition, Chapter 53 now includes all the requirements relating to these issues. ‘Earthing arrangements and protective conductors’, Chapter 54, now incorporates the requirements applicable to equipment with high protective conductor currents which were previously given in Section 607.
Chapter 55, ‘Other equipment’, includes additional requirements to ensure the safe connection of low voltage generating sets, including small scale embedded generators. ‘Luminaires and lighting installations’, Section 559, gives a new set of requirements for fixed outdoor lighting installations, extra-low voltage lighting installations, lighting for display stands and highway power supplies and street furniture (previously in Section 611).
In ‘Inspection and testing’, Part 6, the requirements are generally similar to those in BS 7671: 2001. The minimum values of insulation resistance have been increased. Into Part 7, ‘Special installations or locations’, there are significant changes and additions; Section 607 and Section 611 have been moved into the main body of the regulations (as Sections 543 and 559 respectively).
Perhaps the area causing much speculation prior to the launch of the 17th Edition is Section 701, relating to Locations containing a bath tub or shower basin An important change is that 30mA RCD-protected socket-outlets are permitted beyond a distance of 3m horizontally from the boundary of zone 1. They are prohibited within 3m of zone 1. Zone 3 is no longer defined and supplementary bonding is no longer required, providing the installation has main bonding in accordance with Part 41. Every circuit in the special location, including lighting circuits, must have 30 mA RCD protection.
In Section 704, ‘Construction and demolition site installations’ and Section 705 ‘Agricultural and horticultural premises,’ reduced disconnection times and the 25V equation are no longer included. The requirements relating to caravan parks can now be found in Section 708 and include the requirement that each socket-outlet must be provided individually with overcurrent and RCD protection. The requirements for electrical installations in caravans and motor caravans are now in Section 721.
Part 7 also includes the following new Sections:

Section 709 Marinas and similar locations


Section 711 Exhibitions shows and stands

Section 712 Solar photovoltaic (pv) power supply systems

Section 717 Mobile and transportable units

Section 740 Temporary electrical installations for structures, amusement devices and booths at fairgrounds, amusement parks and circuses

Section 753 Floor and ceiling heating systems.
Appropriate changes have been made to Appendices 1 to 7, in particular the methods and tables used in Appendix 4 and there are also several new Appendices.

Andy in ATL

Thanks Frank--Definitely different. Chris, your post made I head explode. This stuff is interesting. Don't think you are boring your USA brothers with this stuff. I think its cool.

chrisb271

It is mind numbing when you look at it,i should have split it up really Andy.

Seems like there is going to be some new stuff to take in,bit of a task for us older guys


Chris

Andy in ATL

Just got my shiny new 2008 NEC ( national Electrical Code) Its chock full of changes as well. Just to note, where I live, in Georgia, we will not adopt this code until Jan. 1, 2009.

cornishsparks

Seems like we will all be sitting 17th edition regs exams next year. feel sorrry for the lads who have only recently in the last few years taken 16th regs courses to get Part P approved.
Took my 16th edition ten years ago so guess ive been lucky not to have to pay again recently.still will have to pay around £400.00 for the latest couse