Dimmer Flicker

[M Slingsby]

Advice Please..

Installed a 1 gang double dimmer powering, on one side, a triple 3x50w halogen ceiling fitting. On the other side it powers 2 separate 50w halogen switched wall mounted spots connected part way down the line at a simple junction box housed in the roof-space.

The two separate spots flicker when the lamps are dimmed no matter which one or even if both are used. The ceiling fitting is fine.

The dimmer is a standard 400w 240-250v rotary push on-off plastic type.

Is this a dimmer fault or a wiring fault?

 

[rick.oshea]

Are the spots ELV fitted with a 12v transformer or are they GU10's? If powered via a transformer, you may have damaged it, as it may not be a dimmable type - seen some of these flicker before when used with a dimmer

 

[M Slingsby]

Are the spots ELV fitted with a 12v transformer or are they GU10's? If powered via a transformer, you may have damaged it, as it may not be a dimmable type - seen some of these flicker before when used with a dimmer

They are standard 240v GU10 types

 

[M Slingsby]

Any advice?

 

[telectrix]

just todat fitted a double dimmer. one of two wall lights was duff and the other one flickered when dimmer was between 1/3 and 2/3 up. replaced the duff lamp and it worked fine. these were incandecsent 40w candle lamps. could be something to do with not having enough load on the dimmer. sounds daft, but it could be

 

[sparks1974]

i find that having 2 dimmer coils on more than 3 fitings degrades voltage across the circuit , as a rule of thumb i never install 2 dimmers on a 2 way or intermediate circuit

 

[WDMDL]

Because of how the control circuit works in a standard dimmer, it is quite sensitive to fluctuations in line voltage and other distortions to the waveform of the mains.
Those with better filtering perform better in terms of nuisance flicker as a result.

The lower the PSCC is at the origin of the installation, the more prominent the effect will be. (The supply impedance is higher)

You also need a minimum loading, usually this is 40W, but some are 60W (not the OP's problem with 5x50W)

But if the ceiling fitting is DEFINITELY fine, I'd go check your junction box in case one of the conductors hasn't been properly gripped.

Simon.