Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [dimming]

'dimming' is the action of reducing the amount of light emitted from a device.

174 questions
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Cheap and safe way to dim 100+ 60W Incandescent bulbs

For my wedding reception, we are building ~25 lighting fixtures with 4 bulbs each (fixture per table for dinner). For aesthetic and budget reasons, these are 60w "Edison-style" bulbs which we want to dim in order to give a cozy, intimate feeling .…
JackTraore
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Digital Dimmer With Microcontroller

I want to build a digital dimmer for resistive Loads. I have found this circuit for that: The input voltage is 220VAC 50Hz. The red box in the picture is for Zero Crossing Detection. When the AC voltage crosses the zero, the Microcontroller will…
Mehrdad Kamelzadeh
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LED accent light that slowly dims when removed from power source

We've all played with different transformers and power supplies that have an LED indicator that dims before going out entirely when the power supply is unplugged. I'm working on designing an accent light which would involve a translucent crystal…
Thomas
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TRIAC dimmer, circuit design help (resistive load)

Okay guys, I've been tasked with making a light-dimming control system for a 240V heat lamp dissipating around 250W. I need to adjust the heat output on the lamp by control from a microprocessor. I'm developing on an 8051-based SoC with RF circuitry…
Morten Jensen
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Arduino Home Light Dimming

The drywall is just starting to go up in my family’s basement project. I’ve been looking into residential light control systems. Some of the ones I’ve seen have been an upwards of $2,000. I’m thinking it'd be much more fun (and cost effective!) to…
Kevin Mark
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Design considerations for LED strip PWM dimming

A note on my background: I'm a programmer in an electronic design company, starting out with hobby projects. I'm planning to design a PWM LED strip dimmer and colour controller for an RGB/RGBW led strip (yes, this is a hobby project). Before I start…
jaskij
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How are LED Christmas Lights Wired?

I'm planning on building some dimmable lighting controller for Christmas lights, but with LEDs being all the rage nowadays, I was thinking that instead of using triacs and dimming at 60/120 Hz, rectify the AC to DC and use MOSFETs to reduce the…
Nick T
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How to design a snubber for optotriac

I've seen in several places this snubber circuit composed of 2.4K and C1 in this particular case. My question is - what's the purpose of this network exactly and how are the values for the resistor and capacitor calculated? Does it provide a…
miceuz
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Glitch in AC sine wave interfering with phase cut dimming

My company installs ZigBee-based phase cut dimmers for bulbs and LEDs (those which support phase cut dimming). Recently, we encountered a site where we faced a flicker issue. The light is slightly flickering. When the same set of LED driver + LED is…
Whiskeyjack
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1-10V fluorescent lighting digital control

I have a number of fluorescent lights installed that use 1-10V dimming. Note that this is not the same as 0-10V dimming as used in older theatre equipment. The control gear for the lights outputs 10V on the two control wires. When open circuit, the…
colincameron
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Incandescent Light Bulb Soft Start

Is there any circuit to make incandescent bulbs (60-100W) light up more gradually? I've seen many different devices but none of them would work for me. I do not want to just stop the high current spike while the filament is warming up. I want the…
Velociraptor
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Does a dimmed LED lamp draw less power than one at full brightness?

Does a dimmable 6W LED lamp, dimmed to 50%, draw c. 3W? Or does it still draw the full 6W?
user27511
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How to dim an LED with constant current supply?

I have a power RGB led with 350 mA max per color. If I get 3x 300-350 mA constant power supplies will I be able to dim each individual color from 0 to 100% power with Arduino (with NPN transistors)? I am a bit confused since constant current psu's…
DominicM
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Trouble with triac driven dimmer circuit

I have a dimmer circuit that produces the following wave forms. Red: Triac Gate Signal Yellow: 120v 60Hz AC Wave (not triac output) I would assume that given this signal, the triac should flip on and the light and it should be at nearly 100%…
Matt Ruwe
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Estimating apparent LED brightness: current or power?

TL;DR - based on the physics of LEDs, does current or power give a better estimation of actual light output of an LED? I am building a dimmer circuit with a few discrete steps, to operate a COB LED from a constant-current source. I want the steps…
JAE
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