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anyone know if this curcuit will work? Answered

Basically I am building a robot and I have reworked some servos on a rc control to switch current from + to - and back to - and + depending on which way the joystick is. so at the top of the pic is my + - in that can switch to - + I need a curcuit that will run to different relays depending on the direction of current. Will the one I made work. I'm wondering if the power will feedback throught the other relay. by the way the black arrows are diodes Also does anyone know the difference between a reed relay and a regular relay. I looked it up but it doesent make much sense.

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11010010110

10 years ago

it will work. the relays wont short each other 2 diodes are enough. you can skip one diode on each relay to protect from kickbacks when you disconnect power (important if the power in comes from electronics) connect a diode in parallel with the coil of each relay. the direction of diode is such that it does not conduct power under normal conditions

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kendallickes11010010110

Reply 10 years ago

I'm having trouble visualizing where you said to put the other diode. I know the difference in parallel and series but I don't see how/where a diode would work in parallel. My first attempt at this I only used the 2 diodes like you said. For some reason the circuit only worked in one direction I was thinking both relays were kicking but I couldn’t tell for sure. Also I wanted to tell you that I really appreciate your help, you have posted on all of my questions. This is just a hobby for me but I don’t know if I could do it without the support of people like you. Thanks!

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11010010110kendallickes

Reply 10 years ago

the gray diodes in img 1 are the protection diodes in second thought you can make it all with 2 diodes (so that the same diodes make the protection too)

relay.pngrelay2.png
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kendallickes11010010110

Reply 10 years ago

are there any relays that are like a spdt but are normally open and can be pulled to either side?

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11010010110kendallickes

Reply 10 years ago

i guess they may be but very rare why not use 2 relays ? seen only one like that in a 1950s industrial control. its a 3 X 3 X 2 inch beast that can handle 5 A (3 times less than modern 1 X 0.5 X 0.7 inch relays) and can be installed only in a specific direction due to stupid design

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Jordo

10 years ago

I don't know about the circuit, but a reed relay open/closes the circuit when you put a magnet near it.