switch on power off, switch off power on (inverse switch)

[casrip1@gmx.com]

i need help making an inverse switch. i don't know what to google for to get a proper result and i've been digging around a bit and didn't find anything.

 

i need to make a circuit where when a switch is closed, the circuit is incomplete, and when that switch is opened, the circuit is complete.

Edited June 21, 2013 by casrip1@gmx.com

[imatfaal]

But a switch by definition completes a circuit. You will need to specify a bit more about what you need - a switch which is open is just a component on a bit of wire - when it closes it completes the circuit and stuff happens.

[casrip1@gmx.com]

well i'm making a "garage door open" idicator for my mom, she always forgets to close the garage door. i have 2 methods in mind:

 

1. i can set a circuit which would close when the door is open but this will only light up when the door is open fully. i can attach a conductor to the top of the door and another conductor where the track ends, so when the top of the door is open all the way the 2 conductors touch and the circuit is completed, lighting a blub inside.

 

2. this is the one i need help with: i wanna make it so that i have a conductor mounted on the door and it touches the other conductor while the door is closed. but when it opens, the 2 disconnect and this will trigger the light. i like this better than the first idea because the door doesn't have to be open all the way for this to work. even if the door is only open part way, this kind of design would let you know that the door is open.

 

i suspect idea 2 requires 2 circuits, when circuit one is off, the power goes to circuit 2 kind of a thing

Edited June 21, 2013 by casrip1@gmx.com

[Externet]

From the title of your post, a relay does that. When energized, opens a set of contacts (and/or closes another set if fitted)

 

From your explanation; the simple way is to tap onto the circuitry on the door opening (if electric operated) There has to be a built-in switch that knows the door status. Do you have a schematic for it?

Depending on the model (if electric), door opening mechanisms may have an overhead lamp when open. Extending such to a pilot light inside should work.

 

If the door is manually operated, well, a switch at the convenient place will turn on an indicator inside. Probably a few inches from the bottom of tracks.

 

But it is unknown, your skills level and what door you have in order to suggest methods.

[casrip1@gmx.com]

@Externet, my parents don't turst me enough to mess with the internal circuitry of the system, and i don't trust myself enough to mess in there either. so i gotta build an external circuit MacGyver style.

 

i was thinking of using an IC555 like in this circuit http://bit.ly/1c3SkA5

 

BUT replacing the speaker with the LED1 and LDR with a simple switch which would connect to the door. once the door opens, the circuit breaks, and the designated light turns on.

Edited June 21, 2013 by casrip1@gmx.com

[studiot]

I didn't see any need for any timing device (like a 555) in your description.

 

There are various contactless switches you can use which would be entirely independent of the main open/shut drive and controller.

Messing with that may also invalidate the guarantee or service contract on the door.

 

The other advantage of contactless circuit would be that it could be low voltage for safety.

 

I don't know where you are, but I assume the States from your wording so look for proximity switch, 'magnetic switch' , hall effect switch, infrared switch, or mercury tilt switch at firms like Mouser or Digikey.

 

The mercury tilt switch is good for an up and over door because it can be attached to the door and set to switch at almost any angle from vertical. It is a one part switch.

 

All the other types I mentioned are two part. That is one part on the door and one part fixed on the ceiling, wall or floor.

 

You should easily be able to get a cheap module that is ready made.

 

Yes you could also use an infra red or light beam but they are less reliable and things can get in their way easily.

 

go well

Edited June 21, 2013 by studiot

[Externet]

Agree. A 555 circuit has nothing to do here.

Available at any hardware store :

http://www.amazon.com/gp/product/B001337AO2/ref=pd_lpo_k2_dp_sr_2?pf_rd_p=1535523722&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B0050N7SM0&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=0HGRHGFRFQYC2GZW5HVB

 

With not much skills and permissions, think you would have to run wiring to the inside... Well, instead, route a fishing monofilament from the door actuated lever to a flag inside. Can signal the closure by pulling something

 

Just to give a non electrical alternative. And you will have fun...

[casrip1@gmx.com]

screw this, finishing monofilament method it is

 

jk, the magnetic is perfect, just what i was looking for. ill just attach the magnet to the door and the switch parallel to it, and then run the wire inside and setup a simple circuit.

 

thanks everyone for your ideas and input