Dimmer Question

[jonnyollet]

Dear All,

I am looking to replace a standard 3-gang switch with a 3-gang dimmer switch. I have done some reading on wattage selection on these forums and the Varilight website, but just wanted to double check before ballsing it up and setting my house on fire.

The current switch is a standard 1-way, 3-gang switch which controls the following:
1) 2 x 60W (filament bulb) wall lights – total: 120W
2) 1 x 60W (filament bulb) lounge ceiling light – total: 60W
3) 3 x 35W (halogen bulb) hallway ceiling lights – total: 105W

The switch that I am intending to buy is this one (push on/off):
http://www.myswitchshop.com/index.p...o&cPath=3338_3339_3352_3456&products_id=11899

From what I have gathered, the 250W rating is per gang, therefore, I think this switch will be able to cope as none of the three lights exceeds this – can anyone confirm?

One thing, I am not quite sure is the minimum wattage rating. On this switch it is 40W – will this be suitable for my bulbs??

Thanks
Jonny

 

[phatboy]

Correct, it will be fine

 

[JohnW2]

I presume that you've considered this, but the days of filament lamps are definitely numbered, and a dimmer such as you are contemplating installing may well not be compatible with new-fangled (aka much more efficient) alternatives.

Kind Regards, John

 

[jonnyollet]

Phatboy - thanks for your help.

John - I have read that days of filament lamps are limited.
I've stockpiled a few of these...
View media item 77894
I don't think I'd be able to replace this with a halogen or LED or any other type of bulb for that matter.

 

[ericmark]

3) 3 x 35W (halogen bulb) hallway ceiling lights – total: 105W

Looking at wattage I will guess these are GU10 bulbs? Be aware you should not dim quartz halogen bulbs it reduces their life.

The idea of quartz is it is that hot the tungsten from filament will not adhere to the envelope using dimmers can mean the envelope is too cool.

Also a dimmer where you start at low and get brighter as you turn does tend to remove the shock to the bulb and extend their life this will not be the case with push on/off.

Another point is when a bulb blows there should be a fuse built into the bulb which ruptures should you get ionisation of the gas in the bulb when it blows this is often seen as the bulb goes black after and there is a bright flash as it blows. If these as missed as with many cheap imports then as it blows it takes out your dimmer switch so be prepared to swap dimmer switches from time to time as a lamp takes them out as it blows.

Swapping to LED first then using a dimmer designed for LED will remove a lot of the problems. However most LED's just get dimmer the colour does not change. Tungsten also become redder as they dim.

Using a grid switch will be more expensive but you can change just one switch at a time should a bulb blowing take out the unit.

 

[jonnyollet]

Thanks Ericmark.

The halogen bulbs are the standard ones from IKEA:
http://www.ikea.com/gb/en/catalog/products/30138299/

Do you know if these have the built-in fuse? I would have thought they complied to the UK standards?

To be honest, the plan was really to use the dimming function for the filament bulbs (they currently shine to bright and the exposed filament effect is lost) and then just use the halogen bulb with the push on/off part.

 

[ericmark]

Oddly the one bulb I knew where it came from when it failed and welded the contacts so I had to renew fitting came from Ikea it was a 6W CFL which I had selected for an outside light where the central heating flue would trigger a PIR so wanted to just leave on 24/7. I made a big mistake and had a B16 MCB as protection rather than standard B6.

It would be great to know which bulbs are which but it does not seem to matter how much you pay or what name they have it's pot luck. I bought an expensive set of 18 Philips 8W globe bulbs which failed prematurely and were far dimmer than 6 unknown make cheap replacement both in light output and how long they lasted.

Some dimmers are better than others too but how much is by chance and how much by design is again pot luck. I have just one dimmer left it is in this room when they fail I replace with a switch. In bed room I have three switches at door and these do both bedside and ceiling lights and selecting which lamp is used works far better than a dimmer and means you can use any bulb.

 

[jonnyollet]

Would it be better then to get a LED dimmer like the one below and replace the halogen bulbs with LED bulbs?
http://www.myswitchshop.com/index.php?main_page=product_info&cPath=974_975_988&products_id=11273

Would I still be able to use this dimmer with the filament bulbs?

Thanks for all your help.

 

[jonnyollet]

So I bit the bullet, bought and installed the dimmer switch.

I installed the wiring exactly as it was in the old rocker switch:
1) 2 x 60W filament bulb wall lights
2) 1 x 60W filament bulb ceiling light
3) 3 x 35W halogen bulb hallway lights

However, if switch 1) is on, if I turn on switch 2), 1) will then go off briefly before 1) and 2) slow start up together. This is also the case vice versa, if switch 2) is on, and I turn on switch 1), 2) will go off before 2) and 1) slow start up together.

Switch 3) is not affected at all and does not have any effect on the other two.

I am not sure whether this is down to the wiring or the actual dimmer switch. Prior to installing the dimmer switch, the lights were in the same configuration on a normal rocker switch.

Any thoughts?
View media item 78116

 

[davelx]

This may sound obvious, but check that you have wired it " the same as the switches" with reference to the MARKINGS on the terminals, rather than the physical position/order of the terminals.