and/or gates with 120 and 240 volts

GGaudreau

Oct 13, 2014
2
I need to do and and or gates with sensing high voltage,

For example, if I have 1 of 2, or 2 voltages present then i want to be able to drive a relay. An OR gate

I also want to be able to sense if I have 2 12 volts DC, then I want to be able to drive a pump.

Does anyone know how to do this. My electronic knowledge is somewhat limited.

Thanks,
Guy

Gryd3

Jun 25, 2014
4,098
Have you built any circuits before involving AND and OR gates for low voltage?

KrisBlueNZ

Nov 28, 2011
8,393
You can implement AND, NAND, OR, NOR, XOR, XNOR and inversion using relays, by connecting contacts in series (AND function) or parallel (OR function). Relays are available with 110VAC and 230VAC coils. Google relay logic and ladder logic.

Gryd3

Jun 25, 2014
4,098
You can implement AND, NAND, OR, NOR, XOR, XNOR and inversion using relays, by connecting contacts in series (AND function) or parallel (OR function). Relays are available with 110VAC and 230VAC coils. Google relay logic and ladder logic.
That's a face-palm moment... I forgot about relay's and immediately started thinking about 5V logic...

hevans1944

Hop - AC8NS
Jun 21, 2012
4,721
Old-school electromechancal relays are definitely what I would choose.

I once did a ridiculously complicated design using DC relays with steering diodes to implement a raster scan of a motor-driven X-Y table. The X-Y table had a 2.5 cm diameter ZnSe infrared window (or other infrared transparent material) mounted perpendicular to the X-Y plane. The window was raster-scanned through a collimated IR beam from a table-top CO2 laser. Liquid nitrogen-cooled PbSnTe detectors with motor-driven optical choppers in front of them measured incident, transmitted, reflected, and scattered IR radiation from the window material using lock-in amplifiers. This was part of an effort to attract the attention of folks at the Air Force Weapons Laboratory in Albuquerque NM. They were trying to develop high-energy lasers to defend against ballistic missile threats. Later this program was called Star Wars by some pundits. Our demo system must have impressed someone. We received a contract to develop and operate a full-scale test system capable of scanning windows about a meter in diameter. Of course that system had a proper computer to control a large Cincinnati Milacron CNC X-Y milling table that supported the window and its attached cooling hardware.

Relays still have a place in modern circuit design. They are quiet, reliable, low power-consuming, and can be configured with multiple contacts to switch independent circuits with moderate currents of either AC or DC. As @KrisBlueNZ said in post #3 above, using relays for simple AND or OR logic is easy.

GGaudreau

Oct 13, 2014
2
Thank you all - You were very helpfull. Much appreciated. Guy!!

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