So for my school technology project i decided to create a puzzle box that worked like this (ill try to make it concise):

-The overall shape was a cube

-Top face of the cube had two translucent acrylic panels

-One panel has a lightbulb symbol etched on the underside (Panel A)

- Other panel has a question mark etched on the topside (Panel B)

-Purpose of this was for an LED to be placed under Panel A so that when it illuminated, the lightbulb symbol could be seen, and under Panel B a LDR would be placed, so that the question mark on Panel B would already be seen, causing the person who was trying to open the box to be provoked into thinking that the light must be transferred over to Panel B in order for something to happen.

-Therefore, person trying to open the box needs to shine phone light or something similar, which would allow the current to flow from an internal 9 volt battery to a solenoid with a spring on its rod

-This mechanism worked because since there is a spring on the solenoid, the rod is normally inside a drilled hole in a spring loaded drawer (preventing the drawer from coming out of the side of the box), but when the solenoid retracts when it receives the 9 volts it needs to operate, it comes out of the drilled hole, causing the drawer to spring out.

The problem is: the actual circuit board that houses for example the variable resistor to allow me to adjust the light needed by the LDR to allow optimum current flow leeches some of the power from the 9 volt battery, so the solenoid wont work without another power source, and i dont want to do it with the mains electricity, as it would prevent the mobility feature of the box. My teacher suggested that i use a 5 amp SPDT 24VDC relay that has a 6 volt coil, so that i can have another battery snap with another 9 volt battery directly connected from the relay to the solenoid, so that when the relay recieves enough power, the separate 9 volt source will be 'activated', and the solenoid will function.

It is the actual circuit that i'm pretty much useless at, i just know what some of the components are called and vaguely what they do, so any help with that would mean literally everything to me, as it determines my final grade.

I wish i could give you all a better perspective of what im talking about by providing some kind of circuit diagram, but i can only use Solidworks, Livewire and Crocodile Technology at school (which is closed for Easter holidays).

The components that i have as of now:
9v battery (2)
Push to make switch (for led section of circuit)
9v solenoid
5amp 24vdc relay with 6v coil
CBC 548B (npn transistors)
Variable resistor (dont know what kind)
LDR
Average sized LED
Resistors (2)- one for LED part of circuit, and one for LDR part for circuit.

Thanks for any help, it would be unworldly appreciated.

 

Welcome to AAC!

Post a schematic of how you have things connected.

Instead of using a mechanical relay to switch power to the solenoid, you can use a solid state relay or a transistor. A transistor will probably work because I assume the 9V battery is a "transistor" battery, so a general purpose transistor can handle the solenoid coil current.

 

9v solenoid

What resistance, or how much current, is the solenoid?

 

What resistance, or how much current, is the solenoid?

Ive included screenshot of the solenoid's description from Amazon, and it says 6v 800ma, but we tested it when it arrived, and it only worked at an accurate 9volt supply, so going by ratio, would it then be 1200ma?

 

Welcome to AAC!

Post a schematic of how you have things connected.

Instead of using a mechanical relay to switch power to the solenoid, you can use a solid state relay or a transistor. A transistor will probably work because I assume the 9V battery is a "transistor" battery, so a general purpose transistor can handle the solenoid coil current.

Bear with a a minute, ill try to install a trial version of the circuit diagram software i use in school so that i can attach a schematic

 

Ive included screenshot of the solenoid's description from Amazon, and it says 6v 800ma, but we tested it when it arrived, and it only worked at an accurate 9volt supply, so going by ratio, would it then be 1200ma?

The solenoid needs a lot of current. The standard square 9V battery is not going to power it. If that is what you plan to use you need to move to plan B - a bigger battery!

 

You need 4 AA, or AAA batteries. They can source near 1 amp of current and will not "sag" below 6 volts when you try to activate the solenoid.

 

Welcome to AAC!

Post a schematic of how you have things connected.

Instead of using a mechanical relay to switch power to the solenoid, you can use a solid state relay or a transistor. A transistor will probably work because I assume the 9V battery is a "transistor" battery, so a general purpose transistor can handle the solenoid coil current.

Sorry for taking so long, ive got most of the schematic here, just no solenoid component.

Welcome to AAC!

Post a schematic of how you have things connected.

Instead of using a mechanical relay to switch power to the solenoid, you can use a solid state relay or a transistor. A transistor will probably work because I assume the 9V battery is a "transistor" battery, so a general purpose transistor can handle the solenoid coil current.

Sorry for taking so long, the software gave me a bit of trouble. Here is basically all of the circuit except for the solenoid component.

 

Sorry for taking so long, the software gave me a bit of trouble. Here is basically all of the circuit except for the solenoid component.

Show us the complete circuit. Are you okay with changing to a battery that can provide more current?

What is the light and dark resistance of the LDR?

A scan/photo of a hand drawn schematic is fine.