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Transistor relay with NO and NC? Answered

Does anyone know how to make a solid state relay with a NO contact and a NC?
Does anyone have a schematic?
Thanks.

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1
Padlock
Padlock

11 years ago

Easy enough. Use two transistors (or SSRs). Attach the base of one transistor directly to the input (with a resistor, if needed), and another, to a NOT gate, and then to the input. (Again, with the appropriate protection.) I'll make a schematic...

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Padlock
Padlock

Reply 11 years ago

Pardon my spelling mistake, paint doesn't have a spell check.

Schematic.jpg
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thermoelectric
thermoelectric

Reply 11 years ago

Ah, thanks. I don't mind the spelling mistake, lol

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Padlock
Padlock

Reply 11 years ago

Take note that common MUST be ground, or at least lesser than the input voltage.

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Padlock
Padlock

Reply 11 years ago

Correction: Lesser than the input, NO, and NC voltages, (if present). That means that it won't work with AC, and when put in a electrical path the common must be attached to ground. Put bassically, the current must follow the path of the arrow in the transistor. This also means that the input voltage will be using the common as ground. I'm working on another, more complicated version w/ mosfets that would allow AC, and such.

1
Padlock
Padlock

Reply 11 years ago

Scratch the MOSFETs, it's easier to do it like this:

Schematic.jpg
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lemonie
lemonie

11 years ago

What is a NO and what is an NC?

L

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whatsisface
whatsisface

Reply 11 years ago

Normally Open and Normally Closed. Interesting question, I'd say it could be done with gates.

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thermoelectric
thermoelectric

Reply 11 years ago

Oh, I'll have to look into gates....

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Goodhart
Goodhart

Reply 11 years ago

not the Bill kind, either ;-)

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NachoMahma
NachoMahma

Reply 11 years ago

. Normally Open and Normally Closed

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11010010110
11010010110

11 years ago

for small audio signals etc - use c4016 or c4066 for larger signals that flow in one direction only - just use transistors or fets i think there is way to use fets / triacs for 2 way switch (one that can pass current in both directions when closed) each switch you make has its natural attitude NO or NC. if you want to swap it add a not gate (npn transistor) on the control wire

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Goodhart
Goodhart

Reply 11 years ago

A flip flop would work, wouldn't it?

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Derin
Derin

11 years ago

Here is my design.

ssr.jpg
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thermoelectric
thermoelectric

Reply 11 years ago

Ooh, That looks interesting, I will have to try that once I can get my hands on new TRIAC's Thanks