Type of bulbs in a GU10 holder

[ey143]

Can a halogen/incandescent GU10 bulb be used in a LED GU10 lampholder?

Also in the following link http://www.megamanuk.com/lightwaverf/helpdesk/knowledgebase.php?article=12 it says that a resistive load might need to be added because the LightwaveRF cannot pick up low loads. Does the inclusion of such a resistive load of 10w, therefore consume an additional 10w of wasted energy, which if I was to have many circuits around the house needing this 10w load, is unnecessarily wasting my energy and increasing my costs?

The section in question is:
Resistive Load: If you have used LEDs other than the ones recommended above (or the above LEDs with Slave/2 Way Dimmer switches) which flicker when on and/or glow when switched off then this is an indication that there is not enough load in the circuit. Halogen and incandescent lighting give a resistive load equal to their stated wattage while LEDs do not. Having 20W of LED lighting does not necessarily give 20W of resistive load. As a minimum resistive load is required for LightwaveRF Dimmers to operate, erratic behavior can result when this resistance is not met.

A quick way to check if an LED problem you have is resistance related is to temporarily replace one of the LED lamps with a 50W halogen/incandescent lamp. If any problems are resolved then the fix required will be to wire a resistive load in parallel across the circuit. LightwaveRF recommend the Danlers 10W “RESLOADE”. In some cases two may be required.

 

[Iggifer]

Well there is no such thing as an LED GU10 Lampholder, it's just a GU10 lamp holder. Whether you fit LEDs in or not is up to you.

You have two choices, use the lamps recommended by Lightwave, or use the lamps you want to use, and risk having to fit a Resloade or two per dimmer (these are monstrous things that you will have to lose in the downlight hole, not the back of a switch and are about £20 each).

I have had plenty of success dimming Enlite 5W LEDs, but never with Lightwave

What lamps/fittings were you planning on using?

 

[Echo the husky]

Yes to all that. Be aware the Resload is nothing more than a large resistor on a heatsink in a box, it dissipates 10W as heat so care needs to be taken as to where it is located. The plastic tube gets alarming hot after a while, too hot to touch. If I need to fit them I make sure there is free air around them and fit them on a pair of terry clips so the air can circulate around them.

 

[333rocky333]

A Gu10 light fitting designed to take an LED may not be suitable to use with the HEAT from a Gu10 halogen lamp and may even be a fire risk

 

[ey143]

Well there is no such thing as an LED GU10 Lampholder, it's just a GU10 lamp holder. Whether you fit LEDs in or not is up to you.

You have two choices, use the lamps recommended by Lightwave, or use the lamps you want to use, and risk having to fit a Resloade or two per dimmer (these are monstrous things that you will have to lose in the downlight hole, not the back of a switch and are about £20 each).

I have had plenty of success dimming Enlite 5W LEDs, but never with Lightwave

What lamps/fittings were you planning on using?

Not sure yet. Something around £5 each off Amazon.

 

[EFLImpudence]

A Gu10 light fitting designed to take an LED may not be suitable to use with the HEAT from a Gu10 halogen lamp and may even be a fire risk

I know what you mean but how do they design a Light fitting to only take LED lamps?
Put a sticker on it saying LED only?

Isn't that Iggifer's point. A GU10 is a GU10.

 

[ericmark]

Well there is no such thing as an LED GU10 Lampholder,

Actually there is, think it's called a L2 GU10 lamp holder, L2 is the part of the building regulations which requires energy saving bulbs to be used, there is a spike in centre of the holder which matches up with a dimple only found with some GU10 bulbs to satisfy the regulations about not being able to fit non energy saving bulbs into the holder on new build houses.

The GU10 halogen comes in 10 to 75 watt versions although the 75W are rare. The 50W is the standard size. The dimmer switch needs power to run, and there is no neutral at most light switches, the LED can use many methods to regulate current, some will simply switch off once the voltage drops to a low level other have bleed resistors built in, and the net result is one is never sure what LED's will work with what dimmer without looking up the list published by the switch manufacturer.

Since LED's do not change colour when dimmed, having a dimmer does not work in the same way, so having lights spread around different switches works better.

There are LED lamps which you can work directly from your phone, and you can turn them on/off and dim them even when not home. My son looked into the lamps, however they use power all the time, not much but even at 1/2 a watt with 20 lamps it is still 10W 24/7 which can end up using more power than the tungsten lamp it replaces. See this example these also change colour which a stand alone dimmer like the lightwave can't do. There are now many of the so called "Smart bulbs" which are so smart they can even use power when they are not lit.

 

[JohnW2]

There are LED lamps which you can work directly from your phone, and you can turn them on/off and dim them even when not home. ... they use power all the time, not much but even at 1/2 a watt with 20 lamps it is still 10W 24/7 which can end up using more power than the tungsten lamp it replaces.

The number of lamps/bulbs is not really relevant to the arithmetic - the same arithmetic applies separately to each bulb. What you say would only be true when replacing very low power tungsten lamps/bulbs that were hardly ever used. As a more realistic example, if one replaced a number of 40 W tungstens with 5 W fancy LEDs (a saving of 35W per lamp), there would be an (electricity) cost saving if each lamp were 'on' for an average of more than about 21 minutes per day.

Of course, one also has to take into account the increased up-front cost of the fancy LED. I also struggle to understand why anyone would want to go be able to switch/dim lighting when not at home - if it were being done in the name of 'security', that could be achieved by time switches.

Kind Regards, John

 

[ey143]

Is there any electricity cost saving by dimming a bulb because you are not at the brighter setting?

 

[ericmark]

Yes what you say is true, it depends what the bulb is being used for, I use an 8W bulb in the freezer compartment of a fridge/freezer to keep my home brew at the required temperature, it does not matter if tungsten, CFL, or LED I still need 8W to keep the temperature at 20°C in heart of Winter. Non of the options use more or less energy to the others, or do the job better than the others. I get 8W of heat be it direct from bulb, or converted from light into heat in the walls of the freezer. OK maybe an extreme example, but energy is only wasted when it's not required.

With both fluorescent and LED lighting we can get between 90 and 100 lumen per watt, but many lamps are well below that, both fluorescent and LED. So we in this weather need to remove the heat in our homes, be it opening windows at the appropriate times, or using air conditioning units. So during the summer any excess energy is wasted, however exactly the same lighting in winter months is using the energy to heat our houses, so energy is not being wasted. OK electric energy may cost more than gas, so using fluorescent and LED bulbs may still make sense, but they do not save energy.

To dim the bulbs be it fluorescent or LED requires some special considerations, and with LED this includes building the bulb to be able to be dimmed, with the fluorescent it is built into the control gear, but with LED it means that some of the better control gear using pulse width modulated control can't be easily used. So the lamps able to be dimmed drop from 100 lumen per watt to more like 70 lumen per watt.

So we lose energy in the controller, and in the bulb and the bulb likely will have a reduced output or life because the current control is not as good. With a church or other public building there is a safety consideration, when lights dim before going out, people have time to ensure they are safe, and their eyes get use to the reduced light. So yes there is a place for dimming units. But with the lack of ambience and the cost of using dimmable bulbs, there is a lot less reason to use in the home.

It is a cheap method to alter light levels, using up lighters, and ceiling lights where the user can select where and how the room is illuminated is more expensive to install. Although standard lamps and table lamps are quite cheap. But at one time it was felt having dimming switches was the in thing for the latter years of the 20th century, however today in the 21st century it is rather old hat. OK some people want the 80's look to their house, but many have moved on.

 

[JohnW2]

Is there any electricity cost saving by dimming a bulb because you are not at the brighter setting?

Yes, unless it is a very badly designed dimmer. For many bulb types (less with halogens) there is also a considerable increase in lamp life when dimmed.

Kind Regards, John

 

[ericmark]

Is there any electricity cost saving by dimming a bulb because you are not at the brighter setting?

In the main yes. But just as easy to select how many bulbs are used as to dim all the bulbs. And bulbs able to be dimmed with LED typical 70 lumen per watt, those not able to be dimmed 100 lumen per watt. So selecting how many bulbs are used at 100 lumen per watt will use less power then dimming bulbs at 70 lumen per watt.

 

[ey143]

Is there any electricity cost saving by dimming a bulb because you are not at the brighter setting?

Yes, unless it is a very badly designed dimmer. For many bulb types (less with halogens) there is also a considerable increase in lamp life when dimmed.

Kind Regards, John

Why is that i.e. increase in lamp life? Someone else had the discussion about energy cost saving said there was no saving because of the fact that is being resisted and hence getting that buzzing sound. Is that rubbish then?

 

[JohnW2]

Why is that i.e. increase in lamp life?

Because the filament runs cooler.

Someone else had the discussion about energy cost saving said there was no saving because of the fact that is being resisted and hence getting that buzzing sound. Is that rubbish then?

I can't comment properly without seeing that discussion, but it certainly sounds like rubbish.

Kind Regards, John

 

[Iggifer]

Depends how old the dimmer is I suppose.

A modern dimmer doesn't just use a rheostat, they electronically 'chop' the sine wave. This is quite a good example of how they work