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DPDT 12V DC Relay

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yournextboss

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Good day everyone. I saw a post earlier on concerning a relay. The explaination and means of connecting the relay was very helpful which is why I kindly ask for the same method and explaination for my DPDT relay. Please view this web page **broken link removed** ,which has its wiring diagram. a photo of the relay that I'm using and including the circuit that the relay is been used in pdf format. On the relay contacts, could I attach a 12v dc motor instead of the 230v ac motor? How would I connect a small 12v dc motor to the DPDT relay? Any help would be appreciated. Thanks
 

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You can connect the 12v DC motor to the contacts, provided the motor does not take more than 1 amp.

Show a photo of the relay

show the terminals that make the relay "click."

Then get a 12v battery, a 1k resistor and a LED or get the motor and get ready.
 
This should be the data sheet for your relay. The attached image is what should be the pinout of your relay as seen on the data sheet.

Before I forget, I see what I believe is a problem with the circuit, not that it matters for your application. They seem to be switching the line neutral for the motor load and not the line high. That is not a good practice, actually a very poor practice.

You would connect your motor + to either pin 8 or 9 of the relay and motor - to common. Your positive supply would be connected to either pin 4 or 13 and supply negative to common. Note you are using pins 8 and 4 or pins 9 and 8 as either combination will work.

Also as colin55 points out make sure your motor's DC current does not exceed the relay contact ratings. I would stay within 2 amps with a 12 volt motor.

Hope that helps
Ron
 

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Thanks for your great help Colin55 and Reloadron. Before I continue building this circuit contained in the pdf, do any of u guys see anything that will prevent it from working? Are there any other faults to this circuit. Hopefully nothing ,just want to be sure.
 
Laser guided door opener

This is the full circuit with its operation in pdf. Please advice me if there's any fault to this circuit. By the way the IC CD4001 in the circuit is a NOR IC and not a NAND IC. I chose a IR333 laser diode to work with phototransistor PT331C instead of transistor L14F1. Attachments below. Please any help or advice will be greatful.
 

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The circuit is from India. None of their circuits work and I have pages of their circuits, showing the faults in their designs.
The circuit will not work. Not only is the NOR gate drawn incorrectly, but the BC557 will never turn off as Q bar will never rise to 12v as the chip is on a 5v supply. The circuit obviously has never been constructed
What is the purpose of D1?
T2 and T3 do not have to be power transistors. Why have a 5v regulator when the chips will accept up to 15v.
Finally, you don't design a sensitivity circuit as shown in the diagram. It's just a badly designed circuit by a person who is not electronics-capable.
 
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@ Colin55 thanks for your early reply,not exactly what i wanted to read cos it had a tested stamp on the pdf . I just hate people who posts circuits on the web and has a stamp that shows that its tested but end up not working. But i'm glad that u seen the circuit and able to spot their lack of knowledge. Could u pls perhaps help me configure that circuit so that it does end up working? I still want the same principles where i can start a dc motor by triggering a sensor and hopefully some of the components wont be changed as i already bought these components.
 
@ Colin, what a collection. You did one heck of a job on your site with all those circuits. Really nice and informative.

Ron
 
@colin55, in your site it says "The main problem is Qbar. It rises to 5v when HIGH but this allows the BC557 transistor to have a base-emitter voltage of about 7v and this will not turn off the piezo buzzer." How would I turn off the piezo buzzer so that its only activated when then relay is turned on?
 
You don't need the 7805 regulator. It does nothing. Remove it and increase the value of the dropper resistor to the lazer diode. Or simply connect it to the Q output via a 4k7 and BC547 transistor, just like the relay.
T3, R4 and R5 are not needed. Theses three components form a voltage-follower and are not needed.
 
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Did you mean your motor is in series with 230VAC line through L & N pole? You should aware the voltage & current rating of your motor to the voltage and current of your supply (secondary part).
 
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