Home Improvement Stack Exchange is a question and answer site for contractors and serious DIYers. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

In a block of units we installed 240v EARTHED downlights. I believe the neutral maybe 2-3volts above earth causing the lights to flash when turned off. The fittings are provided with earth connection as they are metal and operating at 240. If I disconnect the earth the blink stops. In NSW may the unit board be MENed, would this stop the above earth condition. There is a Core balance breaker on the light circuit

share|improve this question

migrated from electronics.stackexchange.com Mar 8 '13 at 14:29

This question came from our site for electronics and electrical engineering professionals, students, and enthusiasts.

What is a "block of units"? Units of what? What are "NSW" and "MEN"? What is the model of the equipment you are asking about? – gwideman Mar 8 '13 at 1:51
@gwideman, "Block of units" is a housing configuration, run by a landlord. NSW = New South Wales, an Australian State. MEN = Multiple Earth Neutral - Neutral is connected to earth at the distribution board. – bhillam Mar 8 '13 at 2:38
Is the problem specific to double switched circuits? i.e. those with a switch at each end of a corridor or stairway? – Brian Drummond Mar 8 '13 at 11:00

My guess is that you have a dimmer which has a light or LED on it. If this is the case, your particular dimmer does not have a dedicated neutral on it, so in order to power the light/LED, it needs to feed a small amount of current through the lighting circuit. If you had a standard incandescent bulb, this would not be anywhere near enough to cause it to light up, but with CFL's or LED's, this might be enough to cause it to flash.

Purchase a dimmer that has a neutral connection on it (usually these are a bit more expensive). Because it can be powered without powering the rest of the circuit, it will eliminate the flashing light.

share|improve this answer
Steven, I would very much appreciate if you could answer this related question which I just posted: diy.stackexchange.com/questions/30359/… Thanks! – skybreaker Aug 5 '13 at 15:55

Neutral 2-3V above earth is normal. MEN does not normally stop LED/CFL flashing, and you'd still expect 2-3V at the light fitting.

Bad flashing is normally caused by dimmer switches or illuminated switches. One incandescent light on the same circuit will normally stop LEDs and CFLS from flashing by bleeding off any leakage current.

share|improve this answer
Some of the newer dimmers have a threshold setting behind the switch plate that allows a wider range of dimming and crisp cutoffs. I used this model in my house recently for an LED fixture: lutron.com/en-US/Education-Training/Pages/LCE/… I hope they or an equivalent are available locally. – HerrBag Mar 8 '13 at 16:36

I added incorporated an RC circuit using a .47uf capacitor. Works beautifully. ($2.00 capacitor vs $50.00 switch.)

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.