MJLorton Solar Power and Electronic Measurement Equipment Forum

New proof of concept ideas, projects, inventions => New proof of concept ideas, projects, inventions => Topic started by: keepcalmandcarryon on December 03, 2015, 12:12:32 PM

Title: College project Emergency Lighting
Post by: keepcalmandcarryon on December 03, 2015, 12:12:32 PM

Hello Guys,

I am new to the forum, so please be kind. I fact I am new to electronics but I am glad I have started and I am enjoying every moment!

I have a small project to design and build a Emergency lighting circuit and was wondering if you could give me an idea on what my circuit diagram is going to look like.

I thought about using a delay of about 10secs to get the lamp on as I dont want the lamp to come from a sudden level of darkness.

I will be using a DC power supply.
14 V Lamp.
A Relay.
A Light Dependant Resistor (LDR).
I thought about using a potential divider to drive the Relay.

Does anyone have any ideas on what my circuit diagram is going to look like?

Any advice /  help would be gratefully appreciated.

Title: Re: College project Emergency Lighting
Post by: Mr Eastwood on December 04, 2015, 08:43:07 AM

Hi,  welcome to the forum!  :)   sounds like a great project to get stuck into.



Something like this maybe.. (link to website below)

(http://www.circuitstoday.com/wp-content/uploads/2008/04/street-light-circuit.JPG)


Taken from..
http://www.circuitstoday.com/street-light-circuit

Title: Re: College project Emergency Lighting
Post by: keepcalmandcarryon on December 04, 2015, 10:19:34 AM

Quote from: Mr Eastwood on December 04, 2015, 08:43:07 AM

Hi,  welcome to the forum!  :)   sounds like a great project to get stuck into.



Something like this maybe.. (link to website below)

(http://www.circuitstoday.com/wp-content/uploads/2008/04/street-light-circuit.JPG)


Taken from..
http://www.circuitstoday.com/street-light-circuit

Thanks for the circuit, I want the light to come on after a period of 10s, how would I manage to achieve this?

Title: Re: College project Emergency Lighting
Post by: TheNewLab on October 23, 2016, 11:55:43 PM

Hellooooo out there!

I am truly an amateur on this. That said, i believe the amount of time you would like to set it for is based on the resister and capacitor supplying the Light-sensitive diode. You may use formulas and calculate, or have fun and just et a ball park, then tryout different combinations of Caps and Resistors.

I do not remember which, but the relationship between the Transistor and capacitor, one affects the voltage, the other affects the duration.