Dun-Bri Blog

EMC

EMC

 

What is EMC?

 

There are a lot of different abbreviations around, most of them being incomprehensible to ordinary mortals. Probably one of them is EMC.

 

What does it stand for? Why might your company have to bother with it? And how is it put into practice? The information here tries to answer these questions.

 

What does the abbreviation "EMC" stand for? It is short for electromagnetic compatibility. In other words, it is about good neighborliness when it comes to electrical or electronics devices.

 

Any electric or electronic device can emit electromagnetic energy. It acts very much like an unintentional transmitter of electromagnetic energy (similar to a radio transmitter). At the same

time any electronic device can couple into an electromagnetic wave thus acting as a receiver of

electromagnetic energy; very much like a radio receiver.

 

This received energy can cause the electronic device to malfunction.

 

This leads to what is known as essential EMC requirements for electronic devices.

 

The first requirement is that the electromagnetic emissions of such devices must not cause other

equipment to malfunction.

 

The second is that these devices shall be immune to electromagnetic energy.

 

These requirements are very vague and mean different things to different people.

 

In order to standardize these essential requirements the European Union has issued a number of

different directives relating to EMC (e.g. the generic EMC directive or the automotive EMC

directive).

 

These directives are directed at the member states, which are required to transpose them into

national law, i.e. write them into their law books.

 

In the UK they have been transposed and electronics manufacturers should find out if their

products are within the scope of one or another EMC directive.

Airport Beacons CAP168

Airport Beacons CAP168

 

13.2.2     Obstacle lights on vehicles will normally provide sufficient conspictuity by day and night, and obviate the need for marking. However, vehicles intended for continuous use on the movement area and whose size and functions make the particularly hazardous should be both marked and lighted.

 

13.3        Marking of vehicles used on movements areas

 

13.3.1     Vehicles should be marked by colour, preferably yellow for service vehicles and red for emergency vehicles.

 

13.3.2     Vehicles that make infrequent use of the movement areas may meet the marking requirement by carrying flags (see paragraph 12.3.7) or markers (paragraph 12.3.6) when in the movement area, or, if fitted, operate hazard warning lights.

 

13.4        Obstacle lights on vehicles

 

13.4.1     The specification for vehicle obstacle ligts is a s follows

 

                Colour:                   Yellow

Intensity:                No less tha 40 or more than 400tds

Beam Spread:       360° in azimuth and 10° above and below the horizontal except where reduced by lamp supports

Flash Rate:            60 to 90 per minute

 

13.4.2     The lights specified above should be fitted at the highest point of the prime mover vehicle. The highest point of trailers should be fitted with steady red lights not les than 10 candelas.

13.4.3     Obstacle lights on the vehicle should be switched on whenever the vehicles are within the movement area

 

13.4.4     Aerodrome ambulances, fire and rescue appliances may in addition carry blue flashing light for use whilst carrying out emergency duties.

 

13.4.5     If conditions require emergency vehicles, not normally based at the aerodrome, to be called upon for assistance their flashing blue lights should operate while within the movement area.

E Marks

We are seeing an increasing amount of lamp imports coming in from the far east and other countries.

While most of these are fine and carry the correct certification many do not.

Not to bore you too much below is a brief explanation of E marks. But basically if you fit a lamp without an E mark, then that lamp legally should not be used in the EU. If picked up it will fail an MOT and be illegal if the police pick it up.

Also if a fire or accident occurs then using these lights could invalidate you insurance.

So check your emarks when buying your lamps. Dun-Bri does not supply anything un E marked.

If you are told that the country has a reciprocal agreement allowing their lamps to be used in the UK then this is false, the 1989 No. 1796 Road Traffic The road Vehicle Lighting Regulations 1989 ststes that all lamps must have an E mark on it.

Type Approval - E Marks

What is type approval?

• Type approval is the process which ensures that vehicles, their systems and components, meet the appropriate environmental and safety standards. Currently the scheme covers new road vehicles, agricultural tractors, motorcycles and off road vehicles.

1989 No. 1796 ROAD TRAFFIC The Road Vehicles Lighting Regulations 1989

·         This regulations states that if lamps are fitted without E marks where it is required then the lamp is deemed unacceptable for use within the European Union.

·         There are no reciprocal agreements with any country allowing there lamps to used within the EU.

·         All Lamps must display a European E mark

 

1958 Agreement

The core of the Forum's work is based around the 1958 Agreement, formally titled "Agreement concerning the adoption of uniform technical prescriptions for wheeled vehicles, equipment and parts which can be fitted and/or be used on wheeled vehicles and the conditions for reciprocal recognition of approvals granted on the basis of these prescriptions". This forms a legal framework whereby participating countries agree a common set of ECE Regulations for type approval of vehicles and components. When an item is type approved for a regulation by one participating country, then the approval is accepted by all other participating countries.

Originally, the 1958 Agreement allowed participation of ECE member countries only, but in 1995 the agreement was revised to allow non-ECE members to participate.

List of participating countries

As of 2006^[update], the participants to the 1958 Agreement, with their ECE country code, are:

Code Country 1 Germany 2 France 3 Italy 4 Netherlands 5 Sweden 6 Belgium 7 Hungary 8 Czech Republic 9 Spain 10 Serbia 11 United Kingdom 12 Austria 13 Luxembourg 14 Switzerland 16 Norway

Code Country 17 Finland 18 Denmark 19 Romania 20 Poland 21 Portugal 22 Russian Federation 23 Greece 24 Ireland 25 Croatia 26 Slovenia 27 Slovakia 28 Belarus 29 Estonia 31 Bosnia and Herzegovina 32 Latvia

Code Country 34 Bulgaria 36 Lithuania 37 Turkey 39 Azerbaijan 40 Republic of Macedonia 42 European Community 43 Japan 45 Australia 46 Ukraine 47 South Africa 48 New Zealand 49 Cyprus 50 Malta 51 Republic of Korea 52 Malaysia

Most countries, even if not formally participating in the 1958 agreement, recognise the ECE Regulations and either mirror the ECE Regulations' content in their own national requirements, or permit the use and importation of ECE-approved vehicles, or both. The USA and Canada are the two significant exceptions; there ECE regulations are generally not recognised and ECE-compliant vehicles and equipment are not authorised for import, sale, or use in the USA.

Type approval

The 1958 Agreement operates on the principles of type approval and reciprocal recognition. Any country that accedes to the 1958 Agreement has authority to test and approve any manufacturer's design of a regulated product, regardless of the country in which that component was produced. Each individual design from each individual manufacturer is counted as one individual type. Once any acceding country grants a type approval, every other acceding country is obliged to honor that type approval and regard that vehicle or item of motor vehicle equipment as legal for import, sale and use. Items approved as meeting an ECE Regulation are marked with an E and a number, within in a circle. The number indicates which country approved the item, and other surrounding letters and digits indicate the precise version of the regulation met and the type approval number, respectively.

Although all countries' type approvals are legally equivalent, there are real and perceived differences in the rigour with which the regulations and protocols are applied by different national type approval authorities. Some countries have their own national standards for granting type approvals, which may be more stringent than called for by the ECE regulations themselves. Within the auto parts industry, a German (E1) type approval, for example, is regarded as a measure of insurance against suspicion of poor quality or an undeserved type approval.

List of ECE Regulations

As of 2007^[update], there are 123 ECE Regulations. Most regulations cover a single vehicle component or technology. A partial list of current regulations applying to passenger cars follows (different regulations may apply to heavy vehicles, motorcycles etc).

General lighting

• R3 — Retroreflecting devices
• R4 — Illumination of rear registration plates
• R6 — Direction indicators
• R7 — Front and rear position lamps, stop lamps and end-outline marker lamps
• R19 — Front fog lamps
• R23 — Reversing lights
• R37 — Filament lamps (bulbs) (
• R38 — Rear fog lamps
• R48 — Installation of lighting and light-signalling devices
• R77 — Parking lamps
• R87 — Daytime running lamps
• R91 — Sidemarker lamps
• R119 — Cornering lamps
• R123 — AFS lamps

Headlamps

• R1 - Headlamps emitting an asymmetrical passing beam and/or a driving beam, equipped with R2 or HS1 bulbs (superseded by R112, but still valid for existing approvals)
• R5 - Sealed Beam headlamps emitting an asymmetrical passing beam and/or a driving beam
• R8 - Headlamps equipped with replaceable single-filament tungsten-halogen bulbs (superseded by R112, but still valid for existing approvals)
• R20 - Headlamps emitting an asymmetrical passing beam and/or a driving beam and equipped with halogen double-filament H4 bulbs (superseded by R112, but still valid for existing approvals)
• R31 — Halogen sealed beam headlamps emitting an asymmetrical passing beam and/or a driving beam
• R45 — Headlamp cleaners
• R98 — Headlamps equipped with gas-discharge light sources
• R99 — Gas-discharge light sources for use in approved gas-discharge lamp units of power-driven vehicles
• R112 — Headlamps emitting an asymmetrical passing beam and/or a driving beam and equipped with filament bulbs
• R113 — Headlamps emitting a symmetrical passing beam and/or a driving beam and equipped with North America

The most notable non-signatory to the 1958 Agreement is the United States, which has its own Federal Motor Vehicle Safety Standards and does not recognise ECE approvals. ECE vehicles and components therefore cannot be imported or exported between the U.S. and most of the rest of the world without appropriate modifications (federalization). Canada has its own Canada Motor Vehicle Safety Standards, broadly similar to the FMVSS, but Canada does also accept ECE-compliant headlamps and bumpers.

ECE Regulation No 65 Explained

ECE Regulation No 65

 

The full title of Regulation No 65 is Uniform Provisions Concerning the Approval of Special

Warning Lamps for Motor Vehicles.

 

In plain English the term “Special Warning Lamps” means beacons and Lightbars.

 

This Regulation covers things like labelling, colour and light output.

 

What Regulation No 65 means for Lightbars and beacons.

 

There are a lot of different Lightbars available. Many of them are not ECE 65 Lightbars because

they include things not covered by Regulation No 65, e.g. flashers, red or green lenses. It is perfectly all right to sell them in the UK at present (2006) because this ECE Regulation is not compulsory. But if we say that a particular light bar is an ECE 65 light bar, i.e. we stick the appropriate label on, we have to actually comply with Regulation No 65.

 

ECE 65 Lightbars and beacons are type-approved. This means that we are only allowed a limited number of well-defined variants. They are defined by the drawings that we have to submit with the sample Lightbars. This includes putting labels in the all the required places, i.e. at either side and the base of the light bar. ECE 65 Lightbars can be either blue or amber and can have halogen or xenon strobe light sources. If they have halogen light sources they can have one rotator or two coupled rotators per side.

 

Dun-Bri RADEX trailer lighting

Dun-Bri RADEX trailer lighting We are excited to announce the launch of the RADEX trailer lighting range. Highly recommened for the small trailer market. See our website for full details at www.dun-bri.com     For technical specs see http://www.radex.it/indexi.htm Connect with us: Read our blog Contact Us: Tel: 01763 274185 Email: sales@dun-bri.com www.dun-bri.com view email in browser | Remove me from this list

Copyright (C) 2009 Dun-Bri Services Ltd All rights reserved.

Chapter 8 Explained

Chapter 8

 

 

WORKS VEHICLE LIVERY AND USE IN COMPLIANCE WITH

CHAPTER 8 TRAFFIC SIGNS MANUAL 2006 - ISSUED

UNDER THE HIGHWAYS ACT 1980

 

BACKGROUND

The Health and Safety at Work Act 1974 requires all clients, employers and employees to establish and maintain safe systems of work. Statutory undertakers and contractors must give due attention to the detailed traffic management arrangements at road works sites in order to ensure the safety of the public and of their own employees at these obstructions.

Chapter 8 is intended to provide a standard of good practice for the signing and marking of obstructions of the highway.

Chapter 8 has been revised in 2006 and now details more extensive guidance on the conspicuity of vehicles at works sites with respect to colour and high visibility livery. This document sets out the specification that applies to works vehicles engaged in street works in order to meet the new requirements.

The Chapter 8 requirements are more stringent for vehicles stopping on high-speed roads, being any road with a speed limit of 50mph or more. It is recommended that all works vehicles be liveried to this higher specification to eliminate the possibility of breaching the requirements by having works vehicles in the fleet that are not suitable for use at works on certain roads.

 

SPECIFICATION – Example

 

All works vehicles are to be painted white; this meets the requirement detailed in O5.2.1 ‘Any vehicle stopping on the highway for works purposes or inspections should be of a conspicuous colour (e.g. yellow or white)’.

All works vehicles are to be fitted with two independent roof-mounted amber warning beacons visible through 360° in accordance with O5.3.1.

The warning beacons must comply with the requirements of the Road Vehicle Lighting Regulations and should also comply with the United Nations Economic Commission for Europe (UNECE) Regulation 65 on Special Warning Lamps in accordance with O5.3.2.

 

The rear of all works vehicles must be marked with chevron markings comprising alternate strips of fluorescent orange-red retroreflective material and fluorescent yellow non-retroreflective material, of 150mm width each, inclined at 45° to the horizontal and pointing upwards; this meets the requirement detailed in O5.2.3 ‘on high-speed roads, all vehicles stopping on the highway for works purposes or inspections shall be equipped with high visibility rear markings’.

The markings described above should cover as much of the rear-facing portion of the vehicle as possible without obscuring windows, vehicle lighting or registration plates, whilst maintaining where possible the company logo for identification purposes.

 

 

 

O5.1 GENERAL

 

O5.1.1 Production vehicles are rarely suited to site work in their standard form, so before purchasing a vehicle, consideration should be given to the model’s suitability for modifications and its ability to carry the necessary equipment. The ease with which an operator can move from the off side seat to the near side door should also be considered.

 

O5.1.2 The choice of vehicle type, engine size and gearbox should reflect the acceleration and manoeuvrability required of that vehicle during normal working conditions.

 

O5.1.3 All vehicles and equipment shall be checked for correct operation before work commences. All checks should be documented and all faults reported prior to work commencing. If necessary, the vehicle or equipment should be taken out of service until faults are rectified. Basic vehicle checks should always include fuel, lights, oil, water, electrics and tyres.

 

O5.1.4 All site vehicles should, where practicable, have all round visibility, for example, estate cars should be used in preference to vans. Where this is not practicable, additional mirrors should be fitted to eliminate blind spots.

 

O5.2 CONSPICUITY

 

O5.2.1 Any vehicle engaged in works on the highway not in an established works zone should be of a conspicuous colour.

 

O5.2.2 Subject to the specific requirements of the following sections, any works vehicles that are used to protect the workforce or form part of the signing of the works should be of conspicuous colour and appropriate marking. This is particularly important for that part of the vehicle visible to drivers and prescribed as part of any sign mounted on the vehicle.

 

O5.2.3 In addition, on high-speed roads, all vehicles stopping on the highway for works purposes or inspections shall be equipped with high visibility rear markings. High visibility rear markings should comprise either:

 

a) signing to diagram 7403, orb) the alternative light arrow sign in accordance with Section O10.8, or

c) chevron markings comprising alternate strips of fluorescent orange-red retroreflective material and fluorescent yellow non-retroreflective material, of not less than 150 mm width each, inclined at 45-60° to the horizontal and pointing upwards, or

d) a solid block of fluorescent orange-red retroreflective material.

 

The markings described in (c) and (d) above should cover as much of the rear-facing portion of the vehicle as possible without obscuring windows, vehicle lighting or registration plates. Where the main body of the vehicle being used is not a recognised conspicuous colour (yellow or white) then the above markings should be supplemented by a high visibility fluorescent yellow retroreflective strip, of not less than 50 mm wide, along the side of vehicle as a minimum.

 

O5.2.4 Red retroreflective tape shall also be applied to all rear facing edges of open doors, guardrails and equipment lockers.

 

62 GENERAL VEHICLE ISSUES

 

O5.2.5 Where rear facing high visibility markings may be obscured by any device mounted on the vehicle (e.g. lorry-mounted crash cushion (LMCC) or cone laying adaptation), at any time that the vehicle is stopped on a high-speed road, additional markings complying with paragraph O5.2.3 (c) or (d) shall be applied to any face of the device which is displayed to the rear and other road users.

 

O5.2.6 Works vehicles should be kept clean to maintain conspicuity.

 

O5.2.7 Motor vehicles with a maximum gross weight exceeding 7.5 tonnes and trailers with a maximum gross weight exceeding 3.5 tonnes must be fitted with rear markings in accordance with the Lighting Regulations.

 

O5.2.8 Vehicles used for works purposes shall be identified by displaying to the rear the sign to diagram 7404 “HIGHWAY MAINTENANCE”. The sign to diagram 7404 variant “MOTORWAY MAINTENANCE” may be used instead when working on motorways only.

 

O5.3 ROOF-MOUNTED BEACONS

 

O5.3.1 Without prejudice to the specific requirements of the following sections, any vehicle stopping on the highway for works purposes or inspections shall be equipped with either a roof-mounted flashing amber warning light bar (comprising at least two independent light sources) or two independent roof-mounted flashing amber warning beacons, visible through 360°.

 

O5.3.2 Roof-mounted flashing amber warning beacons must comply with the requirements of the Road Vehicle Lighting Regulations and should also comply with the United Nations Economic Commission for Europe (UNECE) Regulation 65 on Special Warning Lamps.

 

O5.3.3 If the main roof-mounted beacon is likely to be obscured from the rear by parts of the vehicle or any equipment carried on the vehicle, additional beacons should be fitted toward the rear of the vehicle where they will remain visible.

 

O5.3.4 The roof-mounted beacons shall be in use when entering, leaving or moving within the site, when travelling in traffic at less than the general traffic speed, and when stationary on the hard shoulder.

 

O5.3.5 When stationary within the confines of a fully installed traffic management arrangement, the roof-mounted beacons shall be switched off, unless they form part of the guarding of the works, e.g. works on minor roads, or are required for mobile works; see Sections O10 and O11.O5.3.6 Vehicles engaged on snow clearing, gritting operations or similar work shall display a flashing amber warning beacon at all times when operating.

New Iveco Daily Rear Lamp

Dun-Bri NEW IVECO Daily Rear Lamp Iveco are using a new lamp for the Daily. This is now in stock at Dun-Bri See our website for full details at www.dun-bri.com Connect with us: Read our blog Contact Us: Tel: 01763 274185 Email: sales@dun-bri.com www.dun-bri.com

Copyright (C) 2009 Dun-Bri Services Ltd All rights reserved.

How to Join Wires

Found this on the Web might be of interest...

There are several different things on the market to join wires together and I will take you through what and when to use them and when not to use them. Let us start with our old friend the "chocolate block" as we know it or "screw terminal connection block" to give it its proper title. I, personally, do not like to see these used in connection with car wiring for reasons that I will explain. Firstly they are very bulky and it's difficult to know if you have screwed them down loosely, or so tightly that you have severed most of the wires and the joint is only held by a strand. You could also trap the insulation underneath the screw and so don't make an electrical connection at all, or the screw head breaks when you are tightening it. Worst of all, the screw has been cross threaded from new and, when you tighten it fully, it doesn't touch the wire at all, leaving you then to wonder why the new unit that you have just installed won't work at all. resulting in countless hours of checking your own work.

Then there are the auto electrician's friend - the crimp connectors. These consist of Butt, Spade, Bullet, Piggy Back, Pin, Fork, Snap Lock, Flag, and closed end connectors. Some of these come with male and female variants. I must admit that I do use these, but not as much as I used to. These items are very safe, if used correctly, but you must have the proper tools to do the job correctly. Merely having cutters and pliers isn't good enough as, in my experience, there is no guarantee of consistent crimp connections being the same, ie . some of them are easy to crimp and some of them need a vice to crimp them. Therefore the only recommended way is with a double crimp ratchet type tool, not cheap but the only way to do the job properly.
Although I started the paragraph saying that I like them, there's a few rules to using these as well. Firstly, don't have any uncovered wire outside the crimp; make sure that you have only enough wire to make the connection safe. If the crimp hole is too large for the wire, then double the wire up to fill the hole. Use only the correct colour crimp for the job. These are:
Red for 0.50-1.5mmsq. Blue for 1.5-2.5mmsq. and Yellow for 4.0-6.0mmsq.
Then there is the cowboy's favourite way of connecting wires together and I' m sure you've all seen it as well; that is to twist the wires together and cover with either, sticky tape, plasters or, if you're really lucky, insulation tape - but not wrapped neatly either.
The way that I prefer to join wires together is with solder and heat shrink sleeving. There is of course a knack to doing this and I'll try to explain it clearly. Firstly you must unwrap the wiring harness far enough back to expose your wire sufficiently. This isn't always easy as you might be on your back underneath the dashboard but it has to be done. Then cut off the required length of shrink wrap sleeving to cover the joint - remembering that it has to go over two wires and, of course, the solder after the joint has been soldered. Then the clever bit: fit the shrink wrap onto the wire, remembering to keep it away from the heat of your iron, or else it will start to shrink before you can get it over the joint!
Remember that you must not have any solder spikes on your joint as these can break through the insulation after it has shrunk, causing it to short out with the next wire when you re-cover the loom with new insulation tape. If there is a need to join more than one wire into an existing loom then the only safe way is to cut the wire in the loom and join the new one with one of the two ends; get your shrink wrap over the biggest soldered end, then resolder the other end onto the joined wires and recover with the shrink wrap and introduce back into the loom. I have seen cases where the insulation has been stripped back a little bit on the wire and the new wire just wrapped around the open joint and then taped. This must not be done as it is very dangerous because it will be impossible to get a sufficiently tight joint to be electrically safe - and therefore can go high resistance and start a fire - especially if you are trying to introduce another live wire, say, for a radio memory or an amplifier.
The most common cause for blown fuses is badly fitted wires, through holes in the metalwork of the car, chafing the insulation and causing a short circuit. If you must go through the metalwork then you should fit a grommet so that your wire cannot chafe. Bad earths are also a reason why things won't work and it is very useful to have the correct tool to find these things. I use a device called a Power Probe. This is connected to the battery live and earth and has a switch on it to give either 12v+ or 12v-. It has a continuity function and tells you whether your wire is live or dead or earthed. When dealing with modern vehicles that have airbags, it is even more critical that, before cutting wires or joining wires to them, you ascertain whether or not they are part of the airbag circuit. There is nothing worse than having that go off in your face and it is very expensive to get them put back. If possible, always join extra lives to the appropriate wires in the fuse box. Very often there will be spares to join to. If there aren't any spares you can always join to the battery terminals themselves. There is a number of slave fuse boxes that you can buy nowadays and all you have to do with these is to find somewhere safe to fit them. Then connect one large, live cable from the battery "+" terminal, and simply use the outputs that you need, with the appropriate fuses.
 
Remember that you should always fit the correct fuse into the circuit if you are making a new one. Also, in the case of fitting car audio amplifiers, make sure that you not only use the correct size of wire for the electrical side but also for the speaker side. If wires have to go under carpets or through the sills then the same rules apply to make sure that they don't go over sharp bits of metal or through holes without grommets. I haven't mentioned, as yet, the advantages, or otherwise, of using insulation tape, so I'll do that now.
 
Insulation tape is worth its weight in gold in certain areas but is a right pain if used in the wrong areas. For example, to reinsulate a wiring loom after work on it, is good, and to cover new wires inside the car loom is good. But beware of fitting it inside the bonnet area as this is a hot spot for plastic wrapping and can cause it to harden and shrink and subsequently come off. There is also the problem of water entering the engine compartment. This, too, can cause the tape to come unstuck and, therefore, to come off. In cases where heat and water may be a problem, you can use either self amalgamating tape or split corrugated tubing that allows you to open it down the split to put the wires inside it thus protecting them. Then, as a rule, you put a bit of self amalgamating tape over each end to protect it and then use tie wraps to attach it somewhere safe away from excessive heat and abrasion from pulleys, belts, fans, etc.
 
I haven't mentioned yet the advantages of using tie wraps as, to my mind, they are the best thing to hit car wiring for a long time. They are neat, you can put them through holes and suspend cables where it wouldn't be possible before, or you can bunch up groups of cables neatly and carefull. I'm sure that you will have your own favourite uses for these things but they really do come into their own when doing work on cars.
Now I'll cover the art of wiring a socket for either a trailer or a caravan. I've seen so many bad ones that this information is essential.
It really isn't hard to do this type of job and, if you only follow the instructions on the socket pack and use the correct cable, (you can even get these pre-wired) then, as long as you connect them into the rear light loom to the correct wires, and re-insulate them afterwards, you can't go wrong. As previously mentioned, I have a power probe which enables me to put the pointed probe into the insulation and gently touch the wire inside without causing any real damage to the outer, other than a tiny little pin prick. By this method I can ascertain its electrical state, ie. live, dead or earth. This isn't quite as easy as it sounds as countless pin-pricks into my hand will show! I've also learnt to carry a box of plasters with me, as blood can stain car upholstery and is difficult to remove. To say that I have seen more cock-ups with this type of wiring would be underestimating the truth, but here is a few things to try to avoid:
Firstly, don't connect your new wiring directly to the rear of the bulb unit, as this not only looks messy but makes it difficult in some cases to change the bulbs when they blow.
Don't trap the wires under the spare wheel or jack, as I have seen this done more times than I can remember.
Don't leave the new wiring where it can get caught by items placed in the boot, or in a tray of water, as boots often accumulate water if the lids don't close properly. As you are probably guessing by now, this is another use for my old mate, the tie wrap, as experience has shown that there are always holes in the rear of the boot that (I would like to think) were made for this purpose. If there are no holes, you can buy a self-adhesive "saddle" with an "eye" for a cable tie.

   

Lux, Lumen and Watts, What’s the Difference?

Found this on the web and thought it was a great article.

http://www.brillianz.co.uk/data/documents/Lumen.pdf

The lux (symbol: lx) is the SI derived unit of illuminance or
illumination. It is equal to one lumen per square metre.
• sunlight on an average day ranges from 32 000 to 100 000 lux
• TV studios are lit at about 1 000 lux [i.e. 1000 lumens
per square metre]
• a bright office has about 400 lux of illumination
• At sunset and sunrise, ambient outdoor light is also about
400 lux (if the sky is clear).
• moonlight represents about 1 lux
• starlight measures a mere 0.00005 lux
Lumens measure "luminous flux". This is a measure of the
total number of packets (or quanta) of light produced by a
light source (e.g. a globe or fluorescent tube). This is the
“quantity” of light emitted by the light source. The purpose of
lux is intended to tell you how many lumens you need given the
area you are trying to illuminate.
Achieving an illuminance of 500 lux might be possible in a
home kitchen with a single fluorescent light fixture with an
output of 1200 lumens. To light a factory floor with dozens of
times the area of the kitchen would require dozens of such
fixtures. Thus, lighting a larger area with the same number of lux
requires a larger number of lumens.
The difference between the lux and the lumen is that the lux
takes into account the area over which the luminous flux is
spread. 1000 lumens, concentrated into an area of one square
metre, lights up that square metre with an illuminance of 1000
lux. The same 1000 lumens, spread out over ten square metres,
produces a dimmer illuminance of only 100 lux.
Now to the issue of watts vs lumens produced. This is a difficult
one because the wattage of a light source refers to the power
consumed to drive the source while lumens refers to the
brightness of that source as the human eye perceives it. The
wattage of course would be the sum of the heat generated as well
the energy of the light emitted.
So, what of LEDs?
“Wattage” of LED Lamps
When evaluating LEDs we are often asked for the wattage of
LED lamps when what is really meant is: “How bright are
they?”. One can only compare the brightness of the various light
sources on the market by knowing the number of lumens they
produce. We have all developed expectations about the how
bright a 20-, 40-, 60- or 100-watt bulb should be and we tend to
apply that frame of reference to LED lamps.
To clarify the relationship of watts to light output and LED
bulbs, we talk about the number of ‘lumens per watt’ (lm/w)
that the device produces. Incandescent bulbs are very
inefficient and only generate around 12 lm/w, whereas LEDs
and halogen sources now have almost equivalent efficiencies
of 40 lm/w. Some fluorescent tubes generate 60 lm/w (which
is where LEDs are predicted to be next year!) It is always
better to talk about lumens (and lux required) than watts when
it comes to lighting decisions.
Just to make things a bit more complex, lumens relate to the
eye’s sensitivity and depend on the wavelength (colour) of the
light. The true point to measure lumens is at 555nm – yellow
green – which is where the eye is most sensitive. White light is
a mix of many colours and to get a proper measure of
‘brightness’ is a complex process involving integration of
lumens over each colour with an ‘eye sensitivity’ weighting
factor ….
Another point to bear in mind is that unlike incandescent light
bulbs that illuminate in a 360-degree spherical pattern
regardless of the shape of the bulb, LEDs depend on the shape
and composition of their lenses and package structure to direct
the light where it is needed. When we illuminate an area with
a ‘spherical bulb’ source, even with a reflector, only a small
proportion (perhaps 50% at best) of the lumens are delivered
as lux to the surface we are lighting – the rest is lost With
LEDs, properly applied, over 80% of the lumens can be
directed to provide lux at the surface. That is why LEDs can
seem such bright pinpoints when you look at them.
So LEDs are as bright per watt as halogen and nearly as
bright as fluorescent – and when properly applied they can
deliver more lux per watt than either of these onto a surface
such as a display case floor.

Series/Parallel wiring.

Series/Parallel wiring.

In any DC generating device such as a battery or solar module, you will always have a negative (-) terminal and a positive (+). Electrons or (current) flows from the negative terminal through a load to the positive terminal. For ease of explanation we shall refer to a solar module or battery as a "Device"   
   

Series Wiring

To wire any device in series you must connect the positive terminal of one device to the negative terminal of the next device.
Important: When you wire devices in series the individual voltages of each device is additive. In other words if each device in the above example had the potential of producing 12 volts, then 12 + 12 + 12 + 12 = 48 volts. If these devices were batteries then the total voltage of the battery pack would be 48 volts. If they were solar modules that produced 17 Volts each then the total voltage of the solar array would be 68 volts.
The second important rule to remember about series circuits is that the current or amperage in a series circuit stays the same. So if these devices were batteries and each battery had a rating of 12 Volts @ 220 Amp hours then the total value of this series circuit would be 48 Volts @ 220 Amp hours. If they were solar modules and each solar module had a rating of 17 volts and were rated at 5 amps each then the total circuit value would be 68 volts @ 5 amps.
Figure 2 shows an example of two 6 Volt 350 Amp hour batteries were wired in series which yields 6 Volts + 6 Volts = 12 Volts @ 350 Amp hours.
If the above devices were solar modules which were rated at 17 volts each @ 4.4 amps then this series circuit would yield 34 volts at 4.4 amps.

Remember the Voltage in a series circuit is additive and the Current stays the same.   

   
Parallel Wiring

To wire any device in parallel you must connect the positive terminal of the first device to the positive terminal of the next device and negative terminal of the first device to the negative terminal of the next device -

Important: When you wire devices in parallel the resulting Voltage and Current is just the opposite of a series circuit. Instead the Voltage in a parallel circuit stays the same and the Current is additive. If each device in the above example had the potential of producing 350 Amp hours then 350 + 350  = 700 Amp hours, the Voltage would stay the same.
If these devices were batteries then this parallel circuit would yield total voltage of 12 volts @ 700 Amp hours. If these devices were solar modules that produced 17 Volts @ 4.4 amps each then the this parallel circuit would yield 17 Volts @ 8.8 amps.

Figure 4 shows four 17 Volt @ 4.4 Amp solar panels were wired in parallel which yields 4.4 Amps + 4.4 Amps + 4.4 Amps + 4.4 Amps = 17.6 amps total @ 17 volts.

if the above devices were batteries which were rated at 12 volts each @ 220 Amps hours then this parallel circuit would yield 12 volts @ 880 Amp hours.
Remember the Voltage in a parallel circuit stays the same and the Current is additive.      

   

Series/Parallel Circuits

Hold on to your hats because here's where it gets a little wild. Actually you've already learned all you need to know to under stand series/parallel circuits. A Series/parallel circuit is simply two or more series circuits that are wired together in parallel.

You might be asking why in the world would someone want to put them self through this ? Well lets say that you want to increase the Amp hour rating of a battery pack so that you could run your appliances longer but you needed to wire the pack in such a way as to keep the battery pack at 12 volts, or you want to increase the charging capacity of your solar array but you needed to wire the solar modules in such a way as to keep the solar array at 34 volts, well, series/parallel is the only way to do that.

Remember in parallel circuits the current is additive so thus you increase your run time or Amp hour capacity or in the case of solar modules, you increase your charging current by wiring the batteries or solar modules in parallel. Since we need 12 volts and have 6 volt batteries or in the case of solar modules we need 34 Volts and have 17 Volt modules on hand on hand, wiring the batteries or solar modules in series allows us to get the 12 Volts or 34 Volts that we need.

An easy way to visualize it would be to start by wiring the batteries in individual sets that will give you the voltage that you need. Lets say that you need 24 volts but have six volt batteries on hand. First wire four of the batteries in series to get 24 volts. (Remember wire in series to increase the voltage) and continue to wire additional sets of four batteries until the batteries are used up.

Next wire each series set of four batteries in parallel to each other (Positive to positive to positive and so on and then negative to negative to negative and so on) until each series set is wired together in parallel. If each series set of batteries equals 24 Volts at 350 Amp hours then five series sets wired to each other in parallel would give you a 24 Volt @ 1750 Amp hour battery pack.

Remember: In a series circuit the current stays the same but the voltage is additive. In a parallel circuit the voltage stays the same but the current is additive.