Need dusk to dawn to partially turn off sign at night

James L

James L

Senior Member
Location
Kansas Cty, Mo, USA
Occupation
Electrician
I'm going to be working on the sign at my church, and they have a particular setup.

Double-sided monument sign
There are (4) LED strips inside now, on a single driver - 2 facing each direction.

The lighting is not bright enough to show through during the day, but it's plenty bright at night

They want to add daytime lighting which would turn off at night.

The question is how to control it

I thought of a digital dusk-to-dawn timer, and a relay with the circuit on the normally closed contacts - to close the circuit during the day when the timer is off, then open the circuit when the timer turns on

Is there a single device that'll do it on a $100 budget?

Dusk to dawn, on during the day, off at night
 
Why not a photocell with the relay to reverse when on haappens?

Many in-wall timers can be programmed for either on or off at set times.
 
Is this an off grid situation with PV and batteries? If so, check Morningstar charge controllers, if they are still a thing. I used them for some similar applications 15 years or so ago.
 
LarryFine said:
Why not a photocell with the relay to reverse when on haappens?

Many in-wall timers can be programmed for either on or off at set times.
Click to expand...
We have 2 thunderstorm seasons each year, and it gets substantially darker when clouds pass over, but can quickly clear up.

I just don't want the sign turning on and off when the clouds are passing
 
LarryFine said:
Actually, I was thinking of this type, about 1/10th the price:

www.homedepot.com

Defiant 15 Amp In-Wall 3-Way Daylight Adjusting Digital Timer Switch with Screw Terminals, White 32648 - The Home Depot

Defiant Digital In-Wall Way Daylight Adjusting Timer with Screw Terminals provides high-precision operation time settings.
www.homedepot.com
Click to expand...
I've used that one before, and that's what I was thinking of in conjunction with a relay to reverse the dusk to dawn. I don't think that unit will reverse it on its own
 
James L said:
I don't want to control it with time because it's a daylight versus night time issue. Our sunrise varies by as much as 3 hours and our sunset varies by as much as 4 or 5 hours from Summer to winter
Click to expand...
That's what "astronomical" timers compensate for; time of year, latitude, and even DST.
 
James L said:
I've used that one before, and that's what I was thinking of in conjunction with a relay to reverse the dusk to dawn. I don't think that unit will reverse it on its own
Click to expand...
I believe it will. "On" vs "off" during timer programming is one of the settings.
 
Photocell connected to a NC ice cube relay or NC contactor.

When the photocell circuit closes, it'll open the relay or contactor and turn the lights off.

Edit.... I assume the nighttime lighting is going to stay on 24/7 and the "daytime" lights are just to supplement them?
 
James L said:
Will that do reverse dusk-to-dawn?

I don't want to control it with time because it's a daylight versus night time issue. Our sunrise varies by as much as 3 hours and our sunset varies by as much as 4 or 5 hours from Summer to winter
Click to expand...
It can be programmed as reverse dusk-to-dawn.
Or dawn-to-dusk :)
Astronomical was already explained here .
 
You must log in or register to reply here.
Top