Lighting Fault - Please Help!

[easty494]

Hi

I recently installed 11no. low voltage recessed downlighters in my living room, controlled by a double dimmer switch (8no. lights on one, 3no. on the other).
The lights every now and again go off for a few seconds, then come back on again. I have checked the connections in each joint box and at the dimmer switch. Any ideas what the problem might be?? I'm 99% sure i fitted the LV version of the dimmer switch.

Any suggestions will be greatly appreciated.

 

[Steve]

What type of transformer and how many? (one per lamp or one for a cluster of lamps?)

Is the transformer big and heavy or small and lightweight?

What wattage are the lamps?

What brand is the dimmer switch? And what is its maximum rated wattage?

One thing to bear in mind is that dimmer switches can only control half their rated load when used with halogens, especially extra low voltage devices, due to the transformers and halogens being a different type of load to standard tungsten filament lamps, placing extra demands on the switch. So a 400 watt dimmer should only be loaded to 200 watt of halogen and so on.

Also if your transformer are big and bulky / heavy, chances are they aren't suitable for dimming, and dimmers aren't suitable for them! You'd need some proper kit to dim them I'm afraid.

Small electronic transformers are available quite cheaply here. You want an electronic one, not a toroidal, preferably one per lamp.

Best to get a new dimmer too, you may have knackered the old one. TLC sell these too, get a good make such as MK or Crabtree.

 

[easty494]

Hi Steve

Thanks for your help. Theres one EmcoGroup LV transformer per fitting. They are the smallish light ones. The lamps are 35W Halogens. The dimmer switch is an MK K4307 POB LV 1 gang double Two Way 2 x (40-300)W/240VA.

From what you're saying then, chances are that this dimmer is probably knackered now, if i replace it with a Triple dimmer (so there is a maximum of 4no. fittings being controlled by each dimmer) should that be okay?

 

[Adam_151]

Make sure the tripple dimmer is rated to 400w per channel, make sure its also suitable for use with elv lighting transformers, in addition ensure that the elv lighting transformers are suitable for use with normal phase cutting dimmers.

Or, get a 6 gang switch and wire them in much smaller groups and control your lighting levels that way

Overkill for you situation, but someone did link to a system based on the dimmers used in theatres where you have a remote dimmer pack and just a control for it on the wall (its hard to build powerful dimmers into switch plates)