So we've all seen this scene dozens of times in movies: a character flips a switch and lights turn on, one at time, down a long tunnel, or throughout a giant garage, or something like that.

I'd like to mimic the effect in my garage and patio, so that all the lights don't come on at once and blind you. But how would I make this effect? From my (limited)research, I can't really find a legitimate electrical or mechanical reason for lights to turn on this way.

  • 2
    It's called Hollywood. In the real world, when you flip the switch, power reaches every light at nearly the same time (assuming the speed of light is close enough to instantaneous for your purposes).
    – BMitch
    Jul 7 '11 at 22:58
  • That what i thought! Now would it be way to difficult to engineer something to cause this effect?
    – Slider345
    Jul 7 '11 at 23:00
  • 2
    The easy way may be to get a lighting team to hide off camera in your backyard, wire each light up to it's own switch, and have them turn on the lights one after another moments after you flip the switch. :)
    – BMitch
    Jul 8 '11 at 1:20
  • 4
    You may also have luck asking the EE SO site how to construct a delayed remote on-off switch in every light and just send the on/off signal (wireless or maybe X10) to your lights with each reacting on their own delay.
    – BMitch
    Jul 8 '11 at 1:22
  • Actually this might be possible, but I think it would be an unwanted side effect of bad starters in florescent lights. And I'm fairly sure in that case it would be difficult to purposely cause this problem, and almost impossible to make it consistent. You will defiantly need some type of delay circuit, designed specifically for this.
    – Tester101
    Jul 8 '11 at 2:16

The easiest thing for you (still requires DIY though) is to buy these - or something similar. They are time delay relays - now you get several versions/modes.

Something like this (PDF)

enter image description here

On/Off Cycle - is what you are looking for i guess. You also get, Interval,Delay-On-Make, Re-Triggerable Single-Shot, etc

Then say you got 5 lights you set and mark each relay from 1-5 setting the delay 1sec,2sec,3sec,4sec,5sec.

Then you attach each of the relays in the order you want the lights to be on (you will know the order because you marked the relay with a number, yea ;) )


you will be left to build your own relays, circuits and logics... to much work.

Which of course you can find all the info (here)

enter image description here

C1 1 See Notes (at link)

R1 1 See Notes (at link)

D1 1 1N914 Diode

U1 1 4011 CMOS NAND Gate IC

K1 1 6V Relay

S1 1 Normally Open Push Button Switch

MISC 1 Board, Wire, Socket For U1


I found this on EBAY- a guy in Poland, near my home town actaully.. wierd.. buildts theses babies! Solid State Relays controlled via USB - if you meassage him i am sure he will tweak and build you something to your needs :)


enter image description here

AND another here..

enter image description here

  • Wow, that relay card is pretty sweet
    – Slider345
    Jul 15 '11 at 15:37
  • BY the looks of it- you can program times on to it. But i suppose the guy can recompile the program to delay each relay by n seconds.. but yea-- its nice.. and not that expensive really.
    – Piotr Kula
    Jul 15 '11 at 15:46

You could do it by making use of Time Delay Relays, but with the cost of parts and effort involved, maybe try just closing your eyes when you flip the switch and open them real slow?

Relays are used for controlling supply of power to an item from a remote switch without having to run the main power through the switch itself.

A common place they are used are in cars, for example on your headlights. Instead of having power go from the battery to the headlight switch then back out to the headlights which would then require the headlight switch be capable of transferring the full amperage required for your headlights (which would make for a more expensive switch and might get pretty warm over time too) a low amp signal goes through the switch and tells the relay when to provide power to the headlights.

A time delay relay works in the same way, but creates a delay between the input signal arriving at the relay and the power being sent down the line.

  • 2
    +1 for "try just closing your eyes when you flip the switch" :-)
    – Slider345
    Jul 8 '11 at 15:31

Depending on how many lights you want to control, it could get expensive, but Insteon devices from smarthome.com, and an Isy99 from universal-devices.com could be used to make this happen. It's fairly straightforward to write scripts that include loops and delays on the Isy99 and you can individually address the plugin modules. I have a reverse version of what you are looking for set up as a "good night" button in our bedroom -- it turns off the lights one-by-one, leaving the last one to slowly dim to off over several minutes.

  • 1
    These lights can be set to ramp up/down (provided the lights you're controlling are dimmable), which is less harsh on your eyes. Depending on what you want, you can have a single switch/circuit (so they'll all still come on together) but you can configure them they'll take a second or two to ramp up to a pre-determined level when you turn the switch on.
    – gregmac
    Jul 18 '11 at 2:27

The reason large arrays of lights are not switched on all at once lies in basic physics:

When switching on an inductove load like a light bulb or fluorescent tube, a shortly-timed voltage spike (and current spike) surges through the system.

If too many bulbs are switched on simultaneously on a single cicuirt, the fuse of this circuit will blow because of the massive spike. If time delay relays are used for groups of lamps, there will be several smaller spikes instead, which the fuse can resist better.

And for a Movie, this looks more dramatic as well ;)

Man-made sources of spikes are usually caused by electromagnetic induction when switching on or off inductive loads (such as electric motors or electromagnets), or by switching heavy resistive AC loads when zero-crossing circuitry is not used - anywhere a large change of current takes place. source

So, timed relays are the way to go for this effect.


You could do this with Home Automation equipment such as X10.

You'd replace your current switch and bulb sockets with ones that can communicate with your home automation controller. Then on the controller configure the lights to act as you want them to.

I don't know a specific model to achieve what you want but I have seen people do similar with home automation.

One example being someone that used motion detectors and light sockets to have the lights come on in a room before you entered it (the motion detectors were in the adjoining rooms).

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