Suitable dimmer switch?

[hyeung]

Hi,

We currently have a single switch that controls 2 sets of lights in our family/dining room. The light fixture itself takes 10 g9 type bulbs at max of 40w. Both sets of lights have the same fixture installed.

Currently I have installed g9 bulbs at a rating of 28w on these lights instead of 40w bulbs. I assume the total max load per light is 400w and with 2 lights on the same switch it's a max load of 800w. However, with my rating of bulbs used this works out at 280w per light and a total load of 560w for the 2 lights.

Anyways here's the question, I want to install a dimmer type switch in place of current single switch. Can you advise on the criteria required on such dimmer switch for my setup?

Also I would actually like to install one of these dimmer products to give home automation abilities - http://mobile.vesternet.com/item/373031
Technical Details
Wireless: Z-Wave (868.42MHz)
Voltage: 110 - 240V AC
Maximum load: 25-500W resistive load. For loads <25W also use Fibaro Dimmer Bypass
Bulb Types: Incandescent bulbs, 230V halogen and dimmable LEDs - not recommended for 12V lighting systems, systems using transformers or fluorescent / compact fluorescent lighting
Power Consumption: < 0.8W
Range: up to 50m (outdoors) and 30m (indoors)
Dimensions (LxWxH): 42 x 37 x 17mm
Firmware Versions: v2.2

But I'm concerned that this may not be suitable for my current lighting fixture setup due the total load?

Once again, can anyone advise?

Thanks,
Hung

 

[ericmark]

I will guess the G9 bulb is not 230 volt but has some voltage dropper. You need to check this to find out if dimmable. Also note the make and power and if leading or lagging.

Most of the voltage dropping devices are switch mode and have a minimum and maximum so 280W dimmed could be as low as 140W so the device would need a rating of 140 - 400W.

Also most G9 are quartz and the whole idea is to keep the quartz so hot the tungsten vapour will not adhere to quartz but will instead return to the element running cold will reduce their life.

With any bulb you have a coiled element and as a result it's not a simple resistive load. With dimming switches this can cause a problem so with a dimmer all parts need to be same make to ensure they will work. Often you can have mixed makes but only sure way is keep to same make.

I have this year removed my last dimming switch. Before the energy saving bulb they were popular but today it's like sticking up a poster "I don't care about the planet." and most people don't care but also don't want to admit it.

 

[winston1]

But I'm concerned that this may not be suitable for my current lighting fixture setup due the total load?

Hung[/quote]

Quite right. 560 watts is over 10% more than 500 watts.

 

[hyeung]

I can confirm that the bulbs I have on these light fixtures are g9 28w halogens and are dimmable (as mentioned in the box packaging). Not sure about the meaning of leading or lagging..

Each light fixture takes 10 g9 bulbs at a max of 40w per bulb. So a combined rating of 400w if I was to use 40w bulbs instead of the 28w equivalents.
Both light fixtures are only controlled by a single one way switch.

Apologies if I'm stating the obvious as my knowledge is very limited on such electricals....
So for my setup, do I just need a dimmer that's rated to atleast 400w? Or do I need to take the rating for both fixtures into account as they are controlled by the single switch...hence I need the dimmer to handle a rating of atleast 800w?
assume the dimmer would need to be a 1 gang 1 way.

So it is the case the zwave dimmer I mentioned earlier is just no good for my setup?

 

[JohnW2]

So for my setup, do I just need a dimmer that's rated to atleast 400w? Or do I need to take the rating for both fixtures into account as they are controlled by the single switch...hence I need the dimmer to handle a rating of atleast 800w?

If you're using 28W lamps, then you need the dimmer to be able to handle 20 of them - i.e. 560W.

So it is the case the zwave dimmer I mentioned earlier is just no good for my setup?

As has been pointed out, 560W is significantly more than the 500W maximum of that dimmer - so, yes, you are correct in saying that it is not suitable for your setup. You might have difficulties in finding dimmers rated for more than 500W, in which case you might have to consider have separate dimmers for each of the fittings.

However, as has been asked are these 230V lamps you're using, or what? This is a crucial question.

Kind Regards, John
Edit: typo corrected

 

[deadshort]

You can install two dimmers, 1 for each light if you can fit the unit in the ceiling void. The existing switch would be bypassed to provide a permanent feed to the dimmer modules at each light. You would then control the dimmers via wireless remote or app.

Regards,

DS

 

[hyeung]

So for my setup, do I just need a dimmer that's rated to atleast 400w? Or do I need to take the rating for both fixtures into account as they are controlled by the single switch...hence I need the dimmer to handle a rating of atleast 800w?

If you're using 28W lamps, then you need the dimmer to be able to handle 20 of them - i.e. 560W.

So it is the case the zwave dimmer I mentioned earlier is just no good for my setup?

As has been pointed out, 560W is significantly more than the 500W maximum of that dimmer - so, yes, you are correct in saying that it is not suitable for your setup. You might have difficulties in finding dimmers rated for more than 500W, in which case you might have to consider have separate dimmers for each of the fittings.

However, as has been asked are these 230V lamps you're using, or what? This is a crucial question.

Kind Regards, John
Edit: typo corrected

They are 240v bulbs as stated in packaging...so how does that change things?

 

[hyeung]

You can install two dimmers, 1 for each light if you can fit the unit in the ceiling void. The existing switch would be bypassed to provide a permanent feed to the dimmer modules at each light. You would then control the dimmers via wireless remote or app.

Regards,

DS

Hmmm not sure if these dimmer modules can fit in the void?
With regards to a separate switch for each fixture....I'm trying to avoid this as I suspect it would involve destruction to both ceiling and the walls in order to wire a separate feed

 

[JohnW2]

They are 240v bulbs as stated in packaging...so how does that change things?

It doesn't - that's fine. The difference between 230V and 240V is neither here nor there. The concern was that they might have been 12V bulbs, fed through some sort of transformer or power supply.

My comments above (and deadshort's) still apply. Dimmable (230V/240V) LEDs might have been a better option, and would certainly have saved a lot on your electricity bills. 560W worth of lamps for, say, an average of 6 hours per day, would/will cost you something like £170 per year to run.

Kind Regards, John

 

[hyeung]

They are 240v bulbs as stated in packaging...so how does that change things?

It doesn't - that's fine. The difference between 230V and 240V is neither here nor there. The concern was that they might have been 12V bulbs, fed through some sort of transformer or power supply.

My comments above (and deadshort's) still apply. Dimmable (230V/240V) LEDs might have been a better option, and would certainly have saved a lot on your electricity bills. 560W worth of lamps for, say, an average of 6 hours per day, would/will cost you something like £170 per year to run.

Kind Regards, John

Thanks John.
I agree very costly indeed....We moved into a showhome new build with these fixtures installed. So not something we choose. Although they are quality and grand looking fixtures, it'd be a shame to replace them just now..they do pump out too much light for most times. Hence the dimmer option...

I did look at the led options before, but not sure if these would be compatible with the fixture. I read something about the need for compatible transformers for led bulbs. Also most of the g9 LEDs look huge in comparison to the standard g9s not to mention the costs.

 

[deadshort]

Hi, you have no need to rewire or add wiring as i explained.

That's the point in wirless lighting control. The light switch would be wireless and programmed to control both dimmer modules in the ceiling void.


If you require a 800w dimmer that would be fitted into a 2g box if you go the wired route.


Regards,

DS

 

[JohnW2]

Hi, you have no need to rewire or add wiring as i explained. ... That's the point in wirless lighting control. The light switch would be wireless and programmed to control both dimmer modules in the ceiling void.

You did indeed explain that (and FWIW I agree with you), but the OP responded ...

Hmmm not sure if these dimmer modules can fit in the void?

... so I'm not clear as to whether it would be possible or not.

Kind Regards, John

 

[333rocky333]

or get 10 watt lamps

 

[hyeung]

Hi, you have no need to rewire or add wiring as i explained.

That's the point in wirless lighting control. The light switch would be wireless and programmed to control both dimmer modules in the ceiling void.


If you require a 800w dimmer that would be fitted into a 2g box if you go the wired route.


Regards,

DS

Hi DS

Thanks for you input..
If I understand correctly these are my options:

1) if I can find a 800w rated single way dimmer, then it's just a swap on the current 1 gang 1 way switch. This would dim both fixtures at the same time.
But no wireless control obviously.

2) Additional wiring required to split the fixtures enabling separate switches to control each. This would mean I could use most standard dimmers of up to 500w; hence get a dimmer each fixture.
Alternatively I could also use 2 wireless dimmers modules.

3) wire a wireless dimmer module to each light fixture where the module will have to be situated within the ceiling void. But doesn't the existing switch need to change in this scenario for the dimming to work?

 

[333rocky333]

1000 watt dimmers are easily available, though in my experiance have a short lifespan