The big problem with LED light is like fluorescent it can produces a 100 Hz pulsed light which can affect some people and also cause a strobe effect, this can be prevented by using a capacitor after the rectifier so some lamps do not have the problem, I had problems with G9 lamps, the local electrical supplier provided these
lamps, which had a flicker problem and also flashed when switched off, a load capacitor stopped the flashing, but only way to stop flicker using local suppliers was to use on quartz lamp.
My wife found on the internet these
lamps, which stopped the flicker, one went faulty so I took it apart to find what was inside it, the current was limited by a capacitor, and fed into a full wave rectifier and a large electrolytic capacitor which which stopped any flicker, the electrolytic capacitor was nearly as big as the previous bulb, and the covers could not be fitted. And the bulb was strictly speaking not allowed for sale in the UK as no wattage or lumen markings, but it worked, I also found a dry joint so repaired the bulb.
However there is no way to read adverts and select bulbs which have no flicker.
The most well-known issue with flicker and strobe lights is the triggering of photosensitive epilepsy.
Children and young-adults up to age 20 are most likely to be diagnosed with epilepsy.
However only 3% of the epileptic population is found to also be triggered by photosensitivity. So although this will be a small segment of the population, these sensitive individuals will need to take extra precautions to avoid flicker which we will outline our suggestions for mitigating flicker in the next section.
Read more here due to lack of packing information the only way at the moment to be sure the bulb will not trigger epileptic problems is to use tungsten bulbs. Yes I am sure one can point a optical device at the bulb to find out if the bulb is smoothed or not, but one is hardly going to get the supermarket to test the bulb before you buy, and once bought it is a bit late, I have a collection of G9 bulbs bought before I found some with no flicker.
I also found when I changed from tungsten to CFL this had a marked effect on the room heating, I found 18°C felt cold in the winter evenings, and found needed to set thermostat to 20°C, I would assume due to the radiant heat from the bulbs when using tungsten it gave a 2°C boost when turning on the lights, so with a lower air temperature air changes would loose less heat, and all rooms could be controlled at a lower air temperature. During the day 18°C was ample when moving around, the cure was a programmable thermostat, but this also resulted in the rooms being warmer when we retired for the night. Where with the tungsten bulb there is an immediate reduction in perceived temperature.
Clearly this will change from home to home, and gas and oil is cheaper than electric so unless all electric heating although the tungsten bulb may save energy in winter, it does not in the main save money.
The other problem is the extra low voltage lamp and the electronic transformer, the electronic transformer will often fit through the hole where the down light fits, where the toroidal transformer is just a little too big, and where a central transformer has been used the extra low voltage supply is often twin flex, i.e. not earth, and the electronic transformer even if it can go from zero and not start at 20 watt is often in the kHz range so can become a transmitter.
In order to save the planet and reduce electronic waste
we have a government directive which says produces must be supported for at least 5 years, so can't comply with this unless quartz lamps are sold at least 5 years after the last electronic transformer with a minimum output of more than 5 watt.
So to stop the sale of quartz 12 volt bulbs would be against the governments own directive. As to dimming switches which need a minimum power or other electronic switches this may mean even 230 volt bulbs would be required in tungsten versions.
I have in the main converted, one or two rarely used lights still tungsten, but I can afford the change, think it wrong to force people to change.
