adam2

I consider a new shortage of carbon dioxide to be likely. The vast majority of carbon dioxide sold in the UK is a by product of fertilizer manufacture. The present exceptionally high price of natural gas has resulted in at least two fertilizer plants suspending operations. "On Wednesday, fertilizer producer CF Industries Holdings said it was suspending operations at both its Billingham and Ince manufacturing complexes due to high gas costs." Quote from report on BBC news website.

Disagree, whilst indoor gas lighting is indeed almost extinct, gas is the default choice for heating and hot water in many venues, especially those that are part of a larger complex such as a school, college, community center, or village hall. Electricity is almost universally used for lighting and small appliances, and with a large proportion of UK electricity being generated from gas, substantial increases in electricity prices seem inevitable. I therefore urge that heating systems be checked for correct operating and that time controls and thermostats are sensibly set. Electrical installations should be inspected for waste caused by inefficient appliances and equipment left turned on when not needed. Since I posted the above, the converter station in Kent that is used to import electricity from France has blown up, 2 GW of imports lost until at least October, and 1 GW lost until next year. 2 GW is about 4% of peak UK demand or about 6% of average demand. This will tend to increase prices of both gas and electricity. News report

UK wholesale gas prices have increased very substantially and the current price is well over TWICE the previous record, and is about FIVE times the norm for this time of year. Discussing the reasons for this could take us into forbidden p0litical areas, but it is an observed fact that the increase has occurred. In time retail prices of both gas and electricity will increase very substantially, gas prices might well double, and electricity prices increase by 50%. I would therefore urge that urgent consideration be given to reducing gas and electricity consumption in performance venues, and of course in ones home. Several energy retailers have gone bust as they have to pay market prices higher than the retail prices they promised to customers. I expect more such failures. Link to 5 year chart of UK gas prices.wholesale gas prices.

If you can do without wireless control and colour changing, this should be doable. 12 volt LED tape, in whatever fixed colour is desired, affixed to frame, battery holders for 8 or 9 AA cells. No switch needed for talent to forget. Have a sensible person insert the batteries 10 minutes before talent due on stage, and remove batteries afterwards. Brightness can be varied a bit by use of 7 cells for dim, 8 cells for medium or 9 cells for bright. Battery run time depends on type of tape and lengths involved, but should get a number of shows per set of batteries.

Large mesh cages are available for storing gas bottles in the open air, but protected against theft. Simply search for "gas bottle cage" on fleabay. Most types are open at the bottom, but can of course be fixed upside down with the opening now at the top. Usually red which is bit ugly, but green or black can be found. the style open at the back is probably what you want.

35 pence an hour sounds about right, it corresponds to about 20 pence a unit which is rapidly becoming the new normal. And even if the electricity cost is less than 35 pence an hour, then the total costs including lamp replacements could easily be as reported. Dimming does not save much, a lamp dimmed to 50% light output uses a lot more than 50% of ratted watts. As regards the running cost of the fluorescent lighting, simply add up the lamp wattages and add up to about 2% for electronic ballasts, or about 15% for newish copper/iron ballasts, or as much as 25% for older types.

This report refers to the often substantial carbon emissions of such events. BBC report. Ceasing use of private aircraft, encouraging train travel to venues, hiring sound and lighting equipment rather than transporting same huge distances, and energy efficiency in general are mentioned. I thought that 1,000 kw or more of incandescent Par cans was a requirement ! and a similar loading of incandescent festoon and halogen site floods for amenity lighting. Favouring venues that are energy efficient was also suggested.

What type of lighting fixtures are used, or proposed for house lights ? If other circumstances permit, it can be preferable to use fixtures that take multiple lamps to give an indirect light reflected from the ceiling. Dimming tends to be imperfect near the bottom of the range. An indirect fitting tends to hide this and give visually better results. If one lamp that is exposed to view, snaps to off at say 30% this gives a displeasing effect. If an indirect fitting contains 6 lamps, one of which snaps to off whilst the other 5 lamps dim, then this looks better. Even if all 6 lamps snap to off, but at slightly different dimmer settings, then the overall effect is not bad.

Most likely reasons in my view for the failure rate are, in order of likelihood. 24/7 Operation, wearing out the fans, sucking more dust and fluff into the lights, and stressing the SMPSUs by continual operation. Being operated from dimmers set to 100% which is not the same as "hard power" High mains voltage, at or even a little above the permitted figure, especially overnight when the load on the DNO network is less. The upper limit is 253 volts (110% of 230 volts) Dishonest persons are introducing failed lights from elsewhere and stealing the good ones. (mark them in some discreet way, or apply an anti tamper seal to the safety wire.) The lights are chinese fakes or copies and not actually made by the reputable brand whose branding they carry.

I was not suggesting that significant amounts of first aid supplies should be carried about ones person, but that stocks held at the venue should be generous. Most of these stocks should be kept in readily available places, box office, management office, back stage etc.

LED filaments could be assembled very simply and cheaply by use of "tag strip" tag strip on fleabay Solder to a suitable piece of tag strip 6 LED filaments and a small power resistor to limit the current to about 0.3 A Paint the dark coloured tag strip white to reflect the light. Tag strip, LED filaments, and resistors are cheap and assembly very simple. 6 LED filaments would give a similar light to a 60 watt incandescent bulb, providing that the led filaments are spaced well apart to aid cooling reliability should be excellent. A 500ma fuse in series with the assembly would be prudent just in case the LEDs go short circuit. 24 volt DC supply via PWM dimmer.

I think that the simplest and most reliable solution would be to use the 3 volt LED filaments as sold on ebay. Connect 3 in series on a 12 volt DC supply, or 6 in series on a 24 volt DC supply. A ballast resistor is essential to limit the current to the proper figure. Dimming via a suitable PWM dimmer. With a high enough frequency, smooth dimming to almost zero should be achievable.

I felt it worth revisiting this old thread to again respectfully urge that public venues review their first aid supplies and firefighting equipment. It would be preferable to go beyond the legal minimum. Substantial re-opening of much of the entertainment industry is within sight. Regrettably such re-opening brings a renewed risk of terrorist attack involving bombs, firearms, bladed weapons and the like. Also an inquiry into the Manchester Arena bombing has suggested that the response by the fire brigade could have been better. My link Detailed discussion of the emergency response is arguably off topic here as it could veer into prohibited p0lit1cal territory. It is however safe to state, that in the event of a major attack, that you/your venue might be "on your own" for a lot lot longer longer than might have been assumed. A series of attacks could also leave the emergency services overwhelmed. First aid supplies and staff training. Fire fighting equipment. Portable lighting equipment. Communications. Blankets to cover the injured or deceased. Remember that in some circumstances, that the police may required that staff and customers "shelter in place" for some time, perhaps beyond the 3 hour duration of most emergency lighting.

WHY?The standard for ELV changed at the same time as LV. If anything all of your old red/black should be changed to brown/blue. Thinking further the red/black was often wrong and realistically the new should, more often than not, be brown/grey replacing red/blue. Of very little real world importance either way. Blue/brown is widely used for the simple reason of availability. Blue/brown is arguably correct for extra low voltage AC PROVIDED THAT one pole of the supply is grounded, and that blue is used for the grounded pole. For an ELV AC supply with neither side grounded then both sides are live and brown/grey as above should be used in theory. Now where can I buy some twin flex with brown and grey cores ? I suppose that someone might make it, but I have never seen any. Note for example that brown/grey SHOULD be used for 110 volts AC from a safety isolating transformer with earthed center tap. Has anyone ever seen this this done ? I have, precisely once and then only for fixed wiring. Flexible cords were blue/brown. For DC it is even more complicated and the approved colours have recently changed AGAIN. Old, old DC colours. DC mains supplies. Positive outer = red, negative outer=blue, center wire =black. 2 wire circuits derived from a 3 wire system, black=neutral, red=live (no matter if the live side was positive or negative) ELV DC such as batteries. Red=positive, black or blue Negative. When polarity unimportant, ELV DC was sometimes both wires white to distinguish from mains voltage AC or DC. Old DC colours Grounded neutral=blue Positive=brown Negative=grey. So 3 wire DC mains were meant to be positive outer=brown, negative outer=grey, center wire=blue 2 wire DC circuits were meant to be blue=grounded neutral, live=brown if negative, and grey if negative. Never seen it done in the wild. New new colours for DC Red for positive, was brown, White for negative, was grey, grounded neutral remains blue. Anyone ever seen this done ? If you buy a small battery with attached wires these are almost always red for positive and black for negative. So back on topic, I would not worry about colour codes on ELV stuff, except that the blue should preferably be used for the grounded side if any.

If an LED lamp is advertised as working over a wide voltage range then it will contain a switched mode power supply. If it is advertised as working on only one voltage or over only a narrow range, then it is probably a simple resistance dropper. It might be worth considering the use of LED "filaments" rather than ready made LED bulbs. These can be driven from a suitable DC supply via a resistance dropper, and dimmed via PWM.. Link to an earlier thread about these LED filaments.LED filaments

It's good to get confirmation on that as I thought it should be the case. I'm ordering a few bits & bobs (including MOSFETs to hook up to an Arduino as a crude PWM dimmer) so we'll see what happens. Yes, but most LED lamps sold these days contain a switched mode power supply and not a simple resistive dropper. The merit of this is that the lamp will operate over a wide range of supply voltages. The main type of LED lamp with a resistive dropper are the very small ones sold for dashboard illumination in cars.

I have just experimented and found that ELV LED bulbs CAN be dimmed but not by any standard type of dimmer. I have some LED lamps intended for DC supply from 10 volts up to 30 volts. They give full light output down to about 11 volts, dim slightly at 10 volts and dim smoothly on lower voltages, going out at about 8 volts. So possible but not very convenient.

12 volt and 24 volt LED bulbs are readily available with standard E27 or B22 caps, they are widely used in buses, yachts, off grid homes, and where mains voltage is prohibited or unwise. Most types are can not be dimmed. Last year I used these in footlights for a basic outdoor stage. Did not attempt dimming but simply a choice of light levels by selective switching. Coloured lamps exist but are rare. "onsolar" offer a range of ELV LED Lamps. One style has two switch selectable output settings. 0.5 watts or 2.5 watts. Use of these lamps would give several brightness settings. VERY LOW=alternate lamps lit at 0.5 watts LOW= all lamps lit at 0.5 watts MEDIUM=Alternate lamps lit at 2.5 watts. FULL= all lamps lit at 2.5 watts. Higher wattage lamps such as 24 volt, 6 watt exist but are not suitable for dimming.

I have installed a number of 5 amp and 15 amp round pin socket outlets in the last few years. Including. 15 amp outlets in a private school for wall mounted electric heaters. 13 amp not used as the heating sockets are time controlled. 15 amp sockets in a local café kitchen for heavy loading appliance that tended to burn out 13 amp plugs. 5 amp sockets in a friends home, for table lamps. Controlled by wall switches unlike the 13 amp sockets. And in an off grid house, both 5 amp and 15 amp outlets for 25 volts DC. 5 amps for lighting, refrigeration, TV, laptop PC, desk fans, Christmas lights and other low loading appliances. 15 amp sockets for kettle, microwave oven, and induction cooking ring. These sockets have become an unofficial standard in off grid premises for 25 volt circuits. The similar style plugs and sockets rated at 2 amps, should not in my view be used in most modern installations. They were designed in the days of small twin twisted lamp flex with single insulation. They are too small to readily accept modern 0.75mm insulated and sheathed flexible cords.

In my view, theatre lanterns in a school or elsewhere DO need PAT testing, but not in most cases every year. If routinely moved from one hall to another, and perhaps dropped or knocked or the flex damaged, then every year is reasonable. In the more typical use, of out of easy reach and seldom disturbed, then every 3 years or every 5 five years might be reasonable. And PAT monkeys really need to be told that there is nothing illegal about 5 amp or 15 amp round pin plugs and sockets. They are still made and installed for a variety of purposes, not JUST theatre lighting.

I suspect that these must be among the brightest and highest efficiency LED lamps yet. The Philips Dubai lamps are even more efficient but available only in small sizes and readily obtainable outside of Dubai. 176 lumens per watt. 42 watt lamp to replace metal halide lamps. Not dimmable. Rather an unlikely choice for production lighting as not dimmable and not compact. Good for working lights to replace the high wattage incandescents often used. Possibly also good for workshops, and for external lighting. Not yet available in the UK but hopefully soon will be. Multi voltage, which is less needed here than in the USA but still useful. My link

I would say turn off when not in use. A little electricity is saved thus, and also the fan is often the weak point in such equipment and running it 24/7 will only shorten the life of the fan, and also suck in more dirt and dust.

I repeat my earlier remark that a 1,200 watt lamp is unlikely to regularly blow a 5 amp fuse. However SOMETHING is clearly operating the fuses. And further investigation is prudent. In particular the following points. A PROPER test and inspection of the lantern that is blowing fuses. Confirm by inspection that the lamp is in fact 1,200 watt, and not some larger lamp that has been bodged to fit. Careful inspection of the plug, the flexible cord and the internal wiring of the lantern. Replace if in doubt. Confirm by inspection that the blown fuses are in fact 5 amps and not some smaller size. School installations are prone to having smaller fuses fitted "for improved safety" Double check for any wrong or mistaken patching. A 1,200 watt lantern sharing a channel with another small lantern could well blow a 5 amp fuse. A formal test and inspection of the wiring between the dimmers and the lanterns.

I would be very surprised indeed if a 1,200 watt lamp is regularly blowing a 5 amp fuse. The degree of overload is very small. It is possible that some other fault or overload exists. More details required. A 1,200 watt lamp designed for 240 volts and used on a 240 volt supply is exactly 5 amps. A 240 volt lamp used on a 230 volt supply is slightly less than 5 amps.

And if work or leisure takes you near open water, do wear a life preserver ! I recently fell into the sea and was glad of said life preserver ! I was standing in an open boat about to offer a helping hand to a kid stepping into the vessel. The child slipped from the pontoon into the boat thereby knocking me into the water. I would probably have been fine without any precautions, but it is well to be cautious. It was a large boat, but definitely a boat and not a ship.