by ericmark »
Wed Jan 22, 2020 8:24 am
I think in real terms tungsten bulbs worked well as we actually used the inferred heat from the bulb it saves turning up the central heating in the evening so they save energy (although if using gas or oil heating not money) as they reduce the air temperature required in the room.
However one should not dim quartz bulbs, I know many do, but if the quartz is not hot enough then the tungsten will deposit on the quartz so reduce the bulb life.
Getting pearl tungsten bulbs suitable for dimming has become a problem, so I have moved to using table and standard lamps so I control the light in the room by how many lights are turned on rather than how bright they are.
First saw it in Turkey where being a lot hotter than here, they went to so called energy saving bulbs well before us, to keep the rooms cooler, they split the lights 1/3 and 2/3 so they had three levels of light without using a dimming switch.
Even in UK there are rooms where getting too hot is a problem, I have used fluorescent lights in the kitchen for years, to give high light with low heat, same with cooker using an induction hob keeps the kitchen cooler, also having kitchen on North side of the house.
Seems odd, but last house main room moved tungsten to fluorescent to LED and each time the watts have reduced and so has the lumen output, was around 3500 lumen now down to around 2300 lumen but is seems brighter, that is until you try to read, only when you try to read do you realise the lumen has dropped, and we ended up with standard lamps behind the seats for when we wanted to read.
As said by Mr White there are different ways to control LED bulbs, the simple way is a capacitor and using them the lumen per watt is not that good, but they can easy be dimmed, a better method is a pulse width modulated control chip, this gives a much better lumen per watt, but it auto corrects voltage drop so is not suitable for dimming. There is also the flashing very fast of the LED which we can't see, but makes them seem brighter, but this is not reflected in the lumen output.
For any electronic switch to work, it needs power, with industry we got the 5-20 mA industrial standard for switching where the first 5 mA is reserved to work the switch with, but we have not seen the same with LED lights, so to power an electronic switch without having a neutral some bulbs have leak through resistor that stop bulb flashing both with the power used by switch, and capacitive and inductive linking in the supply cables, our method of wiring ceiling rose to ceiling rose with drops to the switch was great with tungsten bulbs, but not with LED.
Back in the 1980's I fitted loads of dimming switches, but today I want to control lights without needing to get up and use switches, I have become lazy, I want to as the evening comes to just lean forward and pick up the remote control and turn on lights. Or use phone or tablet.
Great having dim lights when watching TV, but if I want to read anything don't want to get up and turn up lighting, and also found either want it dim or bright, not some where between, so having a switch giving a range of lighting output not really required, in the main just two levels, dim or bright, so standard lamps easier to install than wall lamps so that's the way I have gone.