adam2

BTW, I claim considerable knowledge of electrical matters whether within the entertainment industry or elsewhere, and some knowledge of basic science and general engineering. I make no claim as to up to date knowledge of DMX controls, hence request for info. I will consider the product linked to.

I am considering a couple of cheapo LED PARs for d0m3stic effect lighting. What is the cheapest way to control them ? nothing sophisticated is needed, no programing of chases or fades etc, just a simple manual adjustment of colour and intensity. I was going to buy a "blue only" LED light as I rather like blue. But being able to chose other colours is better. Cheap is good, but simple to use is more important.

True, but most of those multiway sockets would directly take the two pin American plug for which the dodgy adaptor is intended., thereby rendering the adaptor needless.

What a daft product. It would fit some MK sockets that use equal pressure on the live and neutral pins to open the shutters, but as has been said it wont work with most sockets. If one did get a socket to accept it, still dangerous as no fuse.

If an item actually sells on ebay for a grossly excessive price, this can be a way of transferring money from person A to person B and evading the normal controls on money laundering. Suppose that "A" wishes to send £1,850 to "B" Person B lists on ebay an old lighting dimmer for £1,850. Person A buys it and sends the money via paypal. Ebay and paypal fees would be payable, but that can be a price worth paying to make dodgy money look legitimate.

I agree.

Keep the mess in case of war, civil unrest, natural disaster, or terrorist attack ! (remembers English translation of a German civil defence pamphlet that recommended stocks of "destroyed potatoes" amongst other items for such contingencies)

I don't think much of any alleged redundancy in power supplies to London underground ! They no longer have their own generating plant but are totally reliant on the national grid. Supplies to sub surface stations are duplicated but both are derived from the national grid. Network rail derive traction current from duplicated high voltage grid connections. These are on the "V List" of vital national infrastructure, and were NOT cut off during the power failure last August. The drop in frequency disabled large numbers of the new trains, blocking many lines. Railway stations obtain power from the local network like any other customer, many were cut off last august. Basically in a large or regional power cut don't expect any underground or network rail lines to be available. As both entertainment venues and society in general become more reliant on electric power, standby power will become of greater importance. I have a large UPS at home to supply the more important loads for at least 24 hours. All but small and simple venues need to consider similar arrangements.

It may be unrealistic to completely and immediately evacuate the premises in case of a power cut without any other emergency. It might be reasonable for the audience to remain for at least 30 minutes, in case the power comes back on. If someone is taken ill in that time, or if a violent crime occurs, a working telephone is most useful to call the emergency services. After the public have been evacuated, staff should normally check the venue to ensure that no customers remain, if these checks reveal anything amiss, reliable telephone communication is important. Consider also some EXTERNAL emergency such as armed terrorists rampaging, as has happened in France, or in London, in these circumstances sheltering in place might be prudent, or might be ordered by the police. Working telephones again needed. I therefore stand by my earlier remarks that a UPS would be good practice even if not a regulatory requirement.

Even if not a specific regulatory requirement, it would in my view be good practice to fit a UPS in order that the telephone system may be used as normal in a power cut. It could perhaps be argued that provision of reliable telephone communication IS a requirement under general health and safety regulation, for all but the smallest and simplest public venues. Consider for example the consequences of crew, cast, or visitors suffering serious injury in some not obvious part of the premises. And yes, consider also fire and intruder alarm systems that need a phone line. The equipment MIGHT have provision for fitting a back up battery. If not, simply connect the mains input to a UPS. In view of the presumably modest loading. a battery back up time of some hours should be achievable at reasonable cost. Whilst cellphones can certainly be useful, it is in my view most unwise to count on them as an alternative. If the power failure is part of some wider emergency or out of course event, then the cellphone network may be overloaded as vast numbers try to use it. And remember that the cellphone mast needs electricity, which might fail with yours.

Car ignition cable might be found to be too stiff to be ideal for this application, the silicone insulated wire to which I linked, and other similar products, are very flexible.

HT wire Available from fleabay. Other suppliers exist. The above is smaller than 1mm, but should be sufficient for the lamp current. 6Kv wire is thinner and easier to handle and probably adequate in practice, but the 40 Kv wire gives a larger safety margin.

fleabay link Dig the potato waste into the top part of the soil, and sprinkle with compost accelerator of which "garotta" is the best known brand. Addition of this material will greatly accelerate the natural process of decay and turn the waste into harmless compost. Add water if the weather is unusually dry, but otherwise leave well alone.

Have a look on fleabay, suggested search term is "hi bay light" Most of these are intended for discharge lamps. It should be simple to remove or a least disconnect the control gear and then insert an incandescent lamp. You will probably need GES/E40 lamps. These are less popular than in years gone by but are still available. Usual caveats about electrical work.

I feel that a couple of posts are missing the point regarding beam angle. A very narrow beam is required in order to obtain bright moving spots of light reflected from the mirror ball. A wider beam lantern placed closer to the mirror ball will give very poor results. The light from a wider beam lantern when reflected from the ball will continue to spread with the same beam angle. Instead of small bright spots of reflected light you will get large dim patches of light, that may be hardly noticed. This I demonstrated to a sceptic by showing that a 3 watt LED maglight directed at a mirror ball gave far better results than the 50 watt GU10 lamp installed for the purpose.

Or use a transformer. For bright, narrow beam, and low cost, consider vehicle lighting equipment. Look for inexpensive after market car spotlamps that use a 55 watt halogen bulb. Look for units with a plain parabolic reflector and a plain clear front lens. Headlights are not suitable, they give a carefully designed beam, spot lights or front fog lights are what you need. Some types even come with a blue front lens to increase the colour temperature. The narrow beam angle means less light wasted and a 55 watt lamp may be bright enough. The low cost makes multiple units affordable. For full brightness you will need a 14 volt transformer, not 12 volts. 15 volts will be brighter still. Avoid connecting them in series due to being earth return.

I have seen a surprisingly good result in a village hall from a dozen halogen floods as used on building sites, 4 metal halide floods* and a selection of cheapo LED PARS. The halogen floods take very cheap and long lasting lamps and give a good white light. The LED PARS are fine when colours are needed for bands and musicals, and were very cheap. The only real lack is a follow spot. *Donated by myself and intended for shop display lighting, not theatre. Not dimmable. Used with the halogen site floods they give a very bright and even "neutral white" light that is ideal for filming or photography but less suited for a stage production. Used for curtain calls when fond parents want to photograph the little darlings after school plays. The lamps are under £10 each and last for years.

PAR lamps are a bit of a special case, especially the large ones, they are hard to make, the challenges being in glass working rather than being strictly electrical. Regular types of incandescent are not that hard to manufacture, they have been made for over 100 years, and I suspect that manufacture will carry on far into the future, probably of doubtful quality and at very high prices, and limited to the more popular types. And meanwhile LEDs continue to get better and cheaper.

I suspect that the more common incandescent lamps will be available for years to come, but availability of more obscure types will decline. GLS lamps are still available on line despite manufacture or import having been prohibited for some years. If incandescent fixtures see very little use, then stockpiling lamps could be considered. If use is more significant, then LEDs will pay for themselves via reduced energy use. Tungsten lighting is rapidly going the way of carbon arcs, gas lighting, and oil lamps. All of which are still used today, but are not exactly mainstream or popular lighting technologies. I can remember when the local hardware shop sold gas mantles and the more common oil lamp wicks and glasses. Such items are still available today, but only from a handful of specialist suppliers. I can remember when GLS lamps came in DOZENS of different voltages, most of them in a choice of wattages. These days the choice is much reduced. How many people these days want a 160 volt, 80 watt incandescent lamp?

Agree, EL wire is not very bright and probably unsuitable for the O/Ps requirements. To re-use the Christmas star I would either replace the LEDs or use some cheap ready made LED Christmas lights. If wiring up discrete LEDs I would use a very low AC voltage, perhaps 4 or 5 volts, and wire the LEDs in inverse parallel pairs, with a dropper resistance in series with each pair. AC is far preferable to DC in such circumstances as corrosion is less of a problem. Alternatively use cheap ready made battery operated LED Christmas lights powered either from batteries as intended, or via an ELV power supply that is located indoors. Such lights are of course DC but are hopefully better insulated than anything home made and therefore not too vulnerable to corrosion.

What about coloured LED MR16 type lamps ? Generally for 12 volts supply and only use a few watts. If the beam angle is too wide, then consider some form of improvised housing with a focussing lens, readily available in the required red and blue, thereby avoiding losses in a colour filter.

Diverging SLIGHTLY into d0m3stic matters, my bedroom is lit largely by RGB LED tape, a total of 10 meters of tape. I use it mainly for decorative effect but with all three channels on full it is sufficient for reading, and comparable in total light output to a twin 4 foot fluorescent light. The total loading of the LED tape is about 60 watts, and the fluorescent light is about 80 watts, for subjectively a bit less light.

I believe that it could be done. Use good quality bright LED tape. You may need to trial different brands of LED tape and compare relative light output. Several runs of tape per tree. Take great care with the wiring in order to minimise voltage drop. 24 volts is far preferable to 12 volts in this regard.

RS components are IME most useful for obscure or specialist items that are hard to find. Not always best value for "bread and butter" items. They are an approved supplier for most local or national government departments.

Agree that managing the lighting is a large part of the solution. If time permits, rig lanterns as initially seems best, station several observers in different audience seats and observe the prop for any unwanted reflections. If any such are observed, then turn out the lanterns one at a time to ascertain which one(s) are causing the reflections. Then decide if the lighting is acceptable without those lights, if not found acceptable then experiment with other lighting layouts or with the prop slightly differently positioned. I agree that serge is preferable to velvet, but suggest the above experiment in addition.