Blog Sparks Direct
Posts Tagged 17th edition junction box
2010 blog stats for the SparksDirect blog – the most read articles at Blog Sparks Direct
Posted by admin in articles at Sparks, ask Mr Sparks, consumer units, electrical products, in-house announcements, lighting systems, new technologies, products pictures, standards and regulations, switches and sockets, website update on January 7, 2011
Since everyone these days is talking / bragging about their stats, some even inventing top 10 lists and other Best of the Best posts, here we are with a small list of the top 10 pages you, our visitors, paid most attention to in year 2010. Based on the StatPress statistics WordPress gracefully and freely offers, one can see which posts are most “interesting” or “sought for”. You will have to understand though, most of these articles may not be “of interest” to you personally, but people search online for the things they need, and here’s what they find 
We hope that the quality of the articles on our website is improving, and we’re looking forward to more engaging conversations with the visitors and the customers – on the blog!
- The Full Hager Consumer Units Guide to the 17th Edition Wiring Regulations – Part 1 and Part 2(Consumer Unit arrangements) – For well over one hundred years the Wiring Regulations have provided the rules which must be followed to make sure that electrical installations are safe. The introduction of the 17th Edition of the Wiring Regulations on the 1st January 2008 has major implications for all Electrical Contractors, Designers and Consultants. Installations designed from 1st July 2008 must comply with this new set of Regulations. [continue reading...]
- Xenon lights – concealed lighting – picture gallery 2 – All I can say is WOW. Just take a look and admire the following pictures of some more applications(see the first X-Flex picture gallery) of the X-Flex technology of the Xenon lights – from the restaurants to the bathroom and shower lights, conference rooms and bedrooms – you can apply this new technology to everywhere your imagination leads you! [view the pictures...]
- RCD – Residual Current Device, principle of operation; RCD, RCCB, RCBO, CBR and SRCD – What is a RCD? RCD – Residual Current Device – is a generic term for all types of residual current operated device which by definition is: A mechanical switching device or association of devices intended to cause the opening of the contacts when the residual current attains a given value under specified conditions[continue reading...]
- IP rating in the bathrooms – bathroom IP zoning – What is IP zoning, especially for bathrooms? We have also written about IP rating in general, but what about the IP zones in a bathroom? To illustrate the IP zoning regulations, we have divided the bathroom into areas or “zones“, which are classified using the numbers 0, 1, 2[continue reading...]
- Wiring Regulations 17th Edition, BS7671, introduction to the IEE Wiring Regulations – The IET (The Institution of Engineering and Technology) put out some time ago the red-cover book containing the Wiring Regulations 17th Edition, BS 7671 (The IEE Wiring Regulations), which are the national standard to which all domestic and industrial wiring must conform[continue reading...]
- Lights – A large index of the most popular articles introducing the wall lights, spotlights, interior lights, ceiling lights, garden lights, fluorescent lights, etc – found at SparksDirect.co.uk[continue reading...]
- Bathroom lights, over mirror bathroom light, Tallin 300 and Tallin 600 – Bathroom lights – over mirror lights – some of the most recommended, most popular lights for bathrooms are the Tallin series. Today we would like to introduce 2 of the best seller over mirror lights, Tallin 300 and Tallin 600; the main difference between them being their dimensions and the lamp they use[continue reading...]
- Hager guide: Hager Junction Box Guide to the 17th Edition part 2 – this is the second part of the Hager Junction Box Guide to the 17th edition, dealing with Building regulations, downlighter junction boxes, maintenance free connections, etc[continue reading...]
- Switches – great compilation of popular articles introducing wide ranges of switches, sockets, dimmers, dimming systems, switched sockets, socket outlets, fused spurs, etc[continue reading...]
There’s a little something for everyone on our blog! Every day we’re doing our best to introduce not only the products we sell or the ranges we promote, but also some interesting facts about the Electrical Safety, some Rules and Regulations, etc. Keep an eye on the SparksDirect blog for more…
Hager guide: Hager Junction Box Guide to the 17th Edition part 2
Posted by admin in ask Mr Sparks, electrical products, standards and regulations, website update on March 27, 2009
This article is a continuation of the first part of the Hager Junction Box Guide to the 17th edition. Find out more about the
- Building Regulations;
- Requirements of the 17th Edition Wiring Regulations;
- Downlighter Junction Box;
- Maintenance Free Connections;
- Traditional Junction Boxes;
- Conclusions;
- Product Selection Guide;
- Selection Chart.
Maintenance Free Connections
Junction boxes are commonly used during alterations and additions to an installation. With certain exceptions regulation 526.3 requires that every connection shall be accessible for inspection, testing and maintenance. The Electrical Safety Council Technical Manual states that “a junction box with screw terminals is an example of where connections must be accessible”. The reason is to allow inspection of joints which could have relaxed or loosened over time, a recognized problem with screwed terminals.
Unless provision is made for access, where boarding, carpet or other similar covering is laid over a junction box with screw terminals, it may not be considered accessible and maintenance free terminals should be used. This is further reinforced in Appendix 15 of the Wiring Regulations which states “Junction boxes with screw terminals must be accessible for inspection, testing & maintenance or, alternatively, use maintenance-free terminals / connection (Regulation 526.3)”
Maintenance free terminals provide a solution where accessibility is an issue.
Tests, including long term vibration, shock test, long term connection test, pull out, voltage drop, temperature rise and exposure to corrosive atmospheres validate the suitability of these terminals. Equally suitable are solutions such as a ‘joint made by a compression tool’.
Maintenance free terminals have the additional advantages of allowing the direct insertion of solid, stranded or flexible conductors, and allowing the connection of up to four conductors from 0.5mm2 to 4.0mm2(see Hager J501, Hager 803 and Hager J804).
Traditional Junction Boxes
As we have discussed, unless using a solution such as maintenance free terminals, the access to electrical connections should be adequate for their safe and proper inspection, testing and maintenance. In this respect, connections should be in a location where they can reasonably be reached and where there is adequate working space.
Where connections are made in roof spaces and inter-floor spaces the enclosures containing the connections should normally be fixed and provision must be made for their access.
Providing these two constraints are complied with, then the continued use of standard circular junction boxes remains acceptable.
Providing the enclosure is fixed and accessible traditional junction boxes are acceptable.
The requirement for accessibility applies equally to the situation where, because of damage to an existing cable, a repair is effected by the introduction of a joint. The joint must be accessible, alternatively the joint may be made by an appropriate method, a maintenance free terminal for example(see Hager J501, Hager 803 and Hager J804).
Some conclusions regarding the 17th edition compliant Junction Boxes
- Junction boxes are an integral part of virtually every electrical installation. Unfortunately these connections often do not comply with the Wiring Regulations due to incorrect product selection.
- It is clear that careful consideration from designers and installers will be required to meet the requirements of the 17th Edition of the Wiring Regulations.
Product Selection Guide
17th Edition Junction Boxes Selection chart
| Description | No of terminals | Terminal Rating | Reference | Benefits / Considerations |
| Downlighter Junction Box | 3 x 3 x 1.5mm2 1 x 2 x 1.5mm2 |
16A | J501 | Provided with cable clamps and separate terminals for flex |
| Maintenance Free Junction Box | 3 x 4 x (0.5-4.0mm2) 4 x 4 x (0.5 – 4.0mm2) |
32A 20A |
J803 J804 |
Suitable for use in inaccessible locations |
| Traditional Junction Boxes | 4 4 3 6 |
20A 20A 30A 20A |
J201 J301 J401 J601 |
Acceptable for locations which are accessible |
Download this 17th Edition Junction Boxes guide by Hager online here, or read part 1 and part 2 on our website. To purchase online 17th edition junction boxes, visit the Electrical Items section, Accessories, Junction Boxes. Some of the Hager 17th Edition compliant junction boxes are: Hager J501, Hager 803 and Hager J804.
Hager guide: Hager Junction Box Guide to the 17th Edition
Posted by admin in ask Mr Sparks, customer service, electrical products, standards and regulations, technical data, website update on March 26, 2009
For more than one hundred years the Wiring Regulations have provided the rules which must be followed to make sure that the electrical installations are safe. The introduction of the 17th Edition of the Wiring Regulations on the 1st January 2008 has major implications for all Electrical Contractors, Designers and Consultants. All the installations designed starting from the 1st July 2008 must comply with this new set of Regulations. There are regulations concerning the connection of conductors relating to lighting and power final circuits. Read more about the Junction Box guide to the 17th edition(from Hager):
- Building Regulations;
- Requirements of the 17th Edition Wiring Regulations;
- Downlighter Junction Box;
- Maintenance Free Connections;
- Traditional Junction Boxes;
- Conclusions;
- Product Selection Guide;
- Selection Chart.
The Building Regulations & the Electrical Equipment
Since 2005 the Building Regulations for England and Wales have made direct reference to Electrical Installations, increasing the influence on how Electrical Equipment is installed in buildings. The part P of the Building Regulations 2000 came into effect on 1st January 2005 and was further amended on 6th April 2006. This document states that the requirements will be met by adherence to the ‘Fundamental Principles’ for achieving safety given in the Wiring Regulations BS 7671 Chapter 13.
For Scotland, the Building (Scotland) Regulations 2004 apply to domestic and non-domestic buildings. Section 4.5 Electrical Safety in the Scottish Building Standards Agency (SBSA) Technical Handbook prescribes that an electrical installation should be designed, constructed, installed and tested such that it is in accordance with the recommendations of the Wiring Regulations BS 7671. The ‘Fundamental Principles’ that are given in chapter 13 are intended to provide for the safety of persons, livestock and the protection of property against dangers and damage which may arise in the reasonable use of electrical installations.
Good workmanship by competent persons using the proper materials will reduce the risk of overheating or fire: It is recognised that good workmanship by competent persons using proper materials will reduce any hazards that may arise and that every item of equipment shall comply with the appropriate British Standard.
The electrical joints are a potential source of overheating and, if not securely made, could ultimately cause a fire. For this reason there are several regulations relating to electrical connections – these are mentioned in chapter 13 in regulation 134.1.4.
‘Every electrical joint and connection shall be of proper construction as regards conductance, insulation, mechanical strength and protection’.
Requirements of 17th Edition Wiring Regulations BS 7671: 2008
In this section we aim at explaining some of the regulations contained within the 17th Edition Wiring Regulations, regarding the connection of conductors both for lighting and power final circuits.
Electrical Connections
The requirements of the 17th Edition Wiring Regulations concerning electrical connections are covered mostly within section 526. This section states that every electrical connection shall have durable electrical continuity, adequate mechanical strength and protection. The wiring method illustrated here is a common cause of non-compliance particularly with lighting circuits and the connections to downlighters in particular(see Hager J501, Hager 803 and Hager J804).
- It can be seen that the sheath of the flex is not enclosed. This is due to the junction box connection method not facilitating an easy means of enclosing the outer sheath, a non-compliance with regulation 526.9.
- Another problem is that during installation and maintenance, mechanical strain may be placed on the terminations of the conductors within the junction box. This is due to the lack of a clamping method for the cable, a non-compliance with the regulation 522.8.5.
Connections to downlighters are a common cause of non-compliance.
A further potential problem can be found within the junction box (opposite) concerning the type of conductors that are typically terminated. It is often the case in domestic installations that solid twin & cpc cables will be used for the fixed wiring with the conductor to the light fitting (or transformer if the lighting is ELV) being a flexible conductor.
Care must be taken to ensure the strands of the flexible cable are secured adequately in the terminal and have not been damaged to ensure compliance with regulation 526.2.
Also, as can be seen in the illustration on the left, when the conductor was removed for inspection it is clear that some of the strands have been damaged during termination.
Ensure that the connection method selected is fully compliant.
Downlighter Junction Box
When fitting recessed downlighters the following method would overcome all the issues raised previously.
It can be seen here that the sheath of both solid conductors and flexible conductors for the light fitting can be secured as they enter the enclosure. This enables compliance with regulation 522.8.5 in particular where it states that there shall be no undue mechanical strain on the terminations of the conductors. Also regulation 526.9, which requires the cores of sheathed cables from which the sheath has been removed to be enclosed, can be seen to be complied with(see Hager J501, Hager 803 and Hager J804).
Cable clamps prevent strain on terminations for compliance with regulations.
Regulation 526.2 is complied with where the method of connection shall take account of the number and shape of wires forming the conductor. In this junction box solid conductors and flexible conductors can be terminated separately by means of the unique three plate style terminal arrangement(see Hager J501, Hager 803 and Hager J804)..
Continue to read the Hager Junction Box guide to the 17th Edition, part 2.