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dawn simulator

dawn simulator

dawn simulator

(OP)
Ok so I need some help here I am trying to make some lights simulate the rising of the sun, where they would dim at a certain time and also gradually come on at a certain time.  Right now I have the lights (LEDS) running with AC I could wire them with DC if I needed to so that I could do this sun simulation thing. Any help would be much appreciated.

RE: dawn simulator

I'm with IR... I'd write a quick PC program that controls an X-10 dimmer module.  Cost will be around $30 + time to write a quick BASIC program.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: dawn simulator

(OP)
alright well that sounds like a good idea but the only problem now is I don't know how to write the code for it.  If you could tell me what program to write it in or really anything else to help me that would be great, thank both of you.

RE: dawn simulator

(OP)
ok well here is what I would like to do I have a saltwater tank and I could just get a timer and have the timer turn the lights on and off every day at a certain time but I would like to add an automated dimmer to this so it is a more gradual turning on of the lights now this may be more trouble then its worth but I think that it would make the tank healthier that having a sudden burst of light every day and a sudden darkness.  So I would like it to be a self contained unit with no computer, so do you think that this would be more trouble than it is worth or would it not be to hard to accomplish.

RE: dawn simulator

I'd be surprised if there's not already a one-box solution available, but frankly it sounds like you haven't looked.

If I'm wrong, it's surely possible to scrounge an old laptop and set it up in a closet or a corner or under a table to run dimmers and stuff in any combination you can imagine.

However, there are some exceptions.  For fluorescent lights, special equipment is required to dim them, and you probably wouldn't like the results anyway.  Same for CFL.  LEDs may or may not be dimmable, depending on the particulars of their internal drivers.  Have you tried dimming your LEDs by any means yet?  Could you reveal their make/model?



 

Mike Halloran
Pembroke Pines, FL, USA

RE: dawn simulator

If you have LEDs lighting a tank you can not use the dimmers suggested above which chop the power to the fixture(s).  The dimming must be accomplished by the LED driver.   If the driver doesn't have an obvious dimming function you are out of luck.  Snap on and off is how it shall stay.

If your lights are commercial off the shelf LED lights that you just happened to use for your tank there is some small chance that you could use the AC chopping method.  You have to look at the documentation the lights came with.  It has to specifically state  that the LEDs are dimmable.  I doubt it does, but if it does, then you can use the dimming dimming method described above.  

Keith Cress
kcress - http://www.flaminsystems.com

RE: dawn simulator

Well, it still wouldn't be self-contained, but most dimmer modules will ramp up and down on their own; you just wouldn't have much control over the time.  The X-10 lamp modules will ramp up on their own, but the timing would require something like: http://www.x10.com/promotions/mt12a_ed_premiere_0912.html

If you shop around, you should be able to get the dimmer module and timer for easily under $30:
http://shop.ebay.com/?_from=R40&;_trksid=p3907.m570.l1313&_nkw=mt12a&_sacat=See-All-Categories
http://shop.ebay.com/i.html?_nkw=lm465&_sacat=0&_odkw=mt12a&_osacat=0&_trksid=p3286.c0.m270.l1313

Both Z-wave and Insteon have similar products, but they're both considerably more expensive, probably pushing $100.

TTFN

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RE: dawn simulator

(OP)
The LEDs will dim I have put lower volts to a single LED and it is less bright, but I have not tried it with all of them together yet.  Also I have looked and there is not a one-box solution the best that people do is have 1/3 or 1/4 of their lights come on at once and then turn the rest on later.   If you look up what a dawn simulator is they do this with LEDs but on a much smaller scale (with a couple LEDs) this is where I got the idea to do this.  I want to do the same thing but on a much larger scale I currently have 108 LEDs in my custom made lighting system, and this is the minimum number of LEDs I would wan't to do it with.

RE: dawn simulator

Okay, then how about providing a schematic and parts list of your custom made LED lighting system as it is now, so we'll have a clue what to suggest?

 

Mike Halloran
Pembroke Pines, FL, USA

RE: dawn simulator

(OP)
Ok sorry I didn't have anything to draw a real circuit on so I just drew it on photoshop its a very simple design so you should not get lost in it.  all the dots are LEDs there are an even number on blue and white ones.

RE: dawn simulator

Dunno where you are located but over here there are loads of cheap DMX-512 programmable multi-channel lighting controllers available for use in the theatrical and entertainment industries. DMX-512 used to be aimed at the mid range of the market but seems to be everywhere now at remarkably low cost. The effects are programmable from your PC and download to a controller.
  

----------------------------------
  
If we learn from our mistakes I'm getting a great education!
 

RE: dawn simulator

Many years ago I tried to use programmable X10 to have a bedside light turn on slowly in the morning. It didn't work out for my application. The problem was that the light module had to be on in order to be receptive to dim commands. But it would only turn on at full brightness. So the sequence was FULL ON, then dim down to slowly ramp up. Not satisfactory for a gentle sunrise.

The immediately obvious solution was to leave the lamp on fully dimmed overnight, but for some reason that I can't recall, that approach was also unsatisfactory. Perhaps RF noise from the dimmer, I don't recall.

I have no idea if the newer dimmer modules have the same conceptual design characteristic of only turning on full. And perhaps this application could use the dim starting point. Good luck.  

RE: dawn simulator

redxpanda.. The way most people are doing it now for reefs is via a dimmable driver like a meanwell ELN-60-48D (dimmable via a 1-10VDC signal) or with the ELN-60-48P (dimmable via 0-10V PWM signal) There are reef controllers out there already that output both signals for lighting.
I went the DIY route myself..
I have done this using 2 of the ELN-60-48D (running 12 x 3W CREE leds each for my 30G reef tank) For dimming I am using an Arduino microprocessor that is coded to produce the gradual dimming up. Then holding for 8 hours then dimming back down again. You can even program "lightning storms" and "passing cloud" functions if you want.

So either you can take the time to learn some coding (I find Arduino to be a great place to start learning micros) or purchase a premade lighting controller like this or similar http://www.bulkreefsupply.com/store/products/monitors-controllers/digital-aquatics-reef-keepers/rkm-alk-dimmable-t5-and-aqua-illumination-led-controller-digital-aquatics.html

But please learn a little more (start reading the DIY section at www.reefcentral.com or other forum.) LED's are current controlled devices and hooking them directly to AC power and hanging them over a tank of water is NOT a smart idea.  

RE: dawn simulator

I built a system like that many years ago for a guy that raised exotic birds.  He said that there were 60% more offspring when the birds were exposed to a gentle sunrise and sunset.  I used a Z8 chip, that should date me.

RE: dawn simulator

(OP)
mcgyvr  I have had a set up like the one i have built up and running for over three years and have not had any problems so I don't see any reason I should not keep my lighting system the way it is.   

RE: dawn simulator

Congrats on your three years of luck. I hope you have many more.  

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