Moved into an apartment that has MR16 bulbs on the ceiling. A total of 7. Replaced them with 5W Leds and it started flickering. If I use one halogen and 6 LEDs, it doesn't flicker and works fine. The lights have a dimmer switch but i don't want to use it or I keep it on full brightness only. The LEDs are non dimmable. Please advise how to correct the problem.

  1. Should i search for a daylight halogen and use that in one socket to avoid the flickering.
  2. Should I call the electrician and disconnect the dimmer?
  3. Any other solution
  • What make and model is the dimmer switch? Are these 120V or 12V halogens? – ThreePhaseEel Jul 8 '20 at 11:49
  • > LEDs are not dimmable > on dimmer – Harper - Reinstate Monica Jul 8 '20 at 14:26

Yes, the issue is an erroneous assumption that a dimmer which is on “max” is internally bypassed. That is only true for some dimmers, and on those, you can feel a tactile “click” in the high position. A great many more dimmers have such a tactile hard shutoff in the “off” position; that’s so you can change a broken bulb without getting nailed. In actual practice, that “click” can be so stiff that people never push hard enough to even find it; they simply assume the end of the analog range is full-on or full-off.

You might get lucky and find your dimmer does in fact have a “hard on” position. If so, problem solved. Otherwise, yes, what’s called for is either

  • Calling the landlord and getting authorization for a downgrade from dimming to non-dimming switch. Once that is in hand, contact your local permit office on their view toward tenants changing their own light switches: Virtually every AHJ treats a light switch change as too minor to require pulling a permit. As an extension of that, some AHJs will treat it as too minor to bother with the “Only electricians can work in rental units” rule, and that’s the question to put to them.
    • Or if you feel uncomfortable doing such a swap, definitely have an electrician do it. This kind of work can kill you.
  • Your second choice is swap the LEDs out to dimmable types. Get just one. Unscrew all the others. See if the one LED will play nice with the dimmer, and if so, get 6 more. If the one LED will play nice with the dimmer with a halogen present, then get 5 more lol.
  • Your last choice is stay with the situation with 1 halogen.
    • If the color mismatch bothers you, well I can’t stand “daylight color” lighting so I’d get 3000K LEDs...... but it’s possible to color-correct a halogen to 5000/6500K using cinematic gels, which despite the name are actually translucent sheets of plastic sold at your local TV/film/theatre supply store for about $5 for a large sheet. The ones you want have a bluish tint, and get 1/4 strength and layer several of them; that lets you “dial in” the color temp you want. They do melt; position them as far as feasible from the halogen bulb and try not to completely block airflow.
    • You could also get the orange-ish sheets to color-correct the LEDs toward 3000K; but it’s even more important to not block airflow since LEDs cannot run hot.

Option 2 is the cleanest solution to your problem, since "non-dimmable" LEDs hate dimmers and behave strangely with them, as many dimmers do not bypass themselves even at "full" brightness.

I have an LED compatible dimmer and dimmable LEDs where I replaced the dimmer with a switch simply because the dimmer was causing an irritating audible noise in some of the LEDs that a switch did not. It also kept them from getting quite as bright as they could, and had an annoying 1/2 second delay when switched on.

I doubt you'll find a Halogen that will match the color of your LEDs, but if you can stand having one bulb look different it saves the cost of the electrician, especially if this is a rental.

  • It is a rental. I won't mind one bulb looking different but I don't think halogens produce 500lm daylight – Kapil Jul 8 '20 at 11:05
  • Well, halogens don’t have any trouble producing 500lm... lots of lumens in a small space is their specialty. But yeah, 5000k/6500k daylight is hard for them unless you color-“correct” with cinematic gels. Warm-white LEDs are readily available. – Harper - Reinstate Monica Jul 8 '20 at 14:37

Many dimmers advertise that they save $ on your power bill this is because they use an SCR Silicon controlled rectifier these block the current in one direction of the AC all the time then as you dim they turn on later and later in the other cycle.

The problem with this is the halt in current affects the driver so each cycle it is recovering and that causes flicker in some types by adding additional loading it can dampen the affect you see but I read a report not long ago that old style dimmers may be harder on our body’s Especially for those with seizures we may not notice the pulsing but our body can with LED’s more than incandescent those that are sensitive should be using TRIAC based dimmers they control in both directions and the waveform is not as harsh.

If I noticed a flicker I would get an led compatible dimmer save the original and return it when you leave.
The report said the strobe or flicker was much like copy machines to people that were sensitive and are known to cause seizures.

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