can anyone help me please, i need schematic of the laser tripwire circuit with option for alarm to get ON only when the beam is broken and the 2nd option for alarm to get ON when the laser beam is breached and to stop only when the alarm is reseted?!
I already have the dark activated switch see the photo, i need just to ad the relay switch but i have no idea how...
Thanks

 

I already have the dark activated switch see the photo, i need just to ad the relay switch but i have no idea how...

Post a schematic for your existing circuit so we can see what is available to control the relay.

 

Post a schematic for your existing circuit so we can see what is available to control the relay.

I have no schematic, i bought the above dark activated switch at amazon. I want to ad to it the latching relay so the siren can stay on when the laser are breached on ldr

 

I have no schematic, i bought the above dark activated switch at amazon. I want to ad to it the latching relay so the siren can stay on when the laser are breached on ldr

How can we help if you can't tell us what we have to work with?

 

How can we help if you can't tell us what we have to work with?

Did I explained above already?!

 

Did I explained above already?!

If you had explained it sufficiently, I would have offered a suggested solution in my first post.

 

As @dl324 says, you need to provide a visual insight (schematic) of what you really intend to do. We can't just give you a schematic by ourself.
A schematic about the relay board that you purchased would also be helpful. Look at the attachment about a simple dark activated switch circuit.

 

View attachment 154859
can anyone help me please, i need schematic of the laser tripwire circuit with option for alarm to get ON only when the beam is broken and the 2nd option for alarm to get ON when the laser beam is breached and to stop only when the alarm is reseted?!
I already have the dark activated switch see the photo, i need just to ad the relay switch but i have no idea how...
Thanks

You will need to add a relay which has two sets of normally open contacts; one set activate the alarm and one to latch the relay. The relay must have a coil rated for the supply voltage that you are using on your laser tripwire unit. I have drawn a simple circuit for you. It has a normally closed push-button to reset the alarm. The rectifier diode across the relay coil is to protect the contacts in the unit (NOTE the polarity!).

 

You have a few options. You can create a latching relay circuit as KeithWalker was kind enough to provide in post #8 above or just use your existing relay to trigger a SCR. A simple Google of "SCR Alarm Circuits" will bring up a few dozen very simple circuits where your relay contacts, existing, would gate a SCR ON and it will remain on until power to the SCR is removed using a Normally Closed push button switch. Your choice as to how you go about it.

Ron

 

You have a few options. You can create a latching relay circuit as KeithWalker was kind enough to provide in post #8 above or just use your existing relay to trigger a SCR. A simple Google of "SCR Alarm Circuits" will bring up a few dozen very simple circuits where your relay contacts, existing, would gate a SCR ON and it will remain on until power to the SCR is removed using a Normally Closed push button switch. Your choice as to how you go about it.

Ron

Thank you Ron, what kind of relay is it, dpdt or spst? What is pinout of wiring, where to connect the NO, NC, COM, of the relay?
Sorry i am still learning electronics..

 

Thank you Ron, what kind of relay is it, dpdt or spst? What is pinout of wiring, where to connect the NO, NC, COM, of the relay?
Sorry i am still learning electronics..

The relay in my post is double pole/ double throw (DPDT)
The connections to the relay are:
Normally open contact (NO)
Normally closed contact (NC)
Moving contact (COM)
I have revised the diagram to show these:

 

The relay in my post is double pole/ double throw (DPDT)
The connections to the relay are:
Normally open contact (NO)
Normally closed contact (NC)
Moving contact (COM)
I have revised the diagram to show these:
View attachment 154873

Thank you very much, I really appreciate it. Will try the circuit tomorrow. Thanks.

 

Thank you Ron, what kind of relay is it, dpdt or spst? What is pinout of wiring, where to connect the NO, NC, COM, of the relay?
Sorry i am still learning electronics..

The relay you have on your existing little circuit board is a SPDT relay having one normally open and one normally closed contact with a common contact. KeithWalker's drawing uses a DPDT relay where one set of contacts are used to "latch" the relay and the other set are used for your alarm. So the action of the relay on your existing board activates the added DPDT relay which latches itself and it remains latched until the reset button is pressed opening the circuit and unlatching the DPDT relay. This approach is a good and simple circuit way to get to where you want to be. Just look at the circuit and think about what is happening.

Ron

 

The relay you have on your existing little circuit board is a SPDT relay having one normally open and one normally closed contact with a common contact. KeithWalker's drawing uses a DPDT relay where one set of contacts are used to "latch" the relay and the other set are used for your alarm. So the action of the relay on your existing board activates the added DPDT relay which latches itself and it remains latched until the reset button is pressed opening the circuit and unlatching the DPDT relay. This approach is a good and simple circuit way to get to where you want to be. Just look at the circuit and think about what is happening.

Ron

Nothing happened.
The dpdt relay is activated and deactivated simultaneously with the dark light switch, it doesn’t stayed switched ON and on the DPDT relay the alarm is not activated at all?

 

The relay in my post is double pole/ double throw (DPDT)
The connections to the relay are:
Normally open contact (NO)
Normally closed contact (NC)
Moving contact (COM)
I have revised the diagram to show these:
View attachment 154873

Nothing happened.
The dpdt relay is activated and deactivated simultaneously with the dark light switch, it doesn’t stayed switched ON and on the DPDT relay the alarm is not activated at all?

 

Nothing happened.
The dpdt relay is activated and deactivated simultaneously with the dark light switch, it doesn’t stayed switched ON and on the DPDT relay the alarm is not activated at all?

If wired like Keith's drawing it should latch. My guess here is something is not wired like the drawing. Relay latching circuits like this are very common. Check your wiring.

Ron

 

Nothing happened.
The dpdt relay is activated and deactivated simultaneously with the dark light switch, it doesn’t stayed switched ON and on the DPDT relay the alarm is not activated at all?
I think you have wired the relay contacts wrongly. Make sure that you have the wires connected to the common and normally open contacts of the latching relay.

 

Nothing happened.
The dpdt relay is activated and deactivated simultaneously with the dark light switch, it doesn’t stayed switched ON and on the DPDT relay the alarm is not activated at all?

I think you have wired the relay contacts wrongly. Make sure that you have the wires connected to the common and normally open contacts of the latching relay.

 

I think you have wired the relay contacts wrongly. Make sure that you have the wires connected to the common and normally open contacts of the latching relay.

I spent all day but can’t make it,
It is this pinout correct on the relay. See the photo. What side on the coil is ground and plus?

 

hi ek,
This clip is from the relay d/s, your diagram is OK.
The power connection to coil can be either way, not polarised.
E