Home made energy saver

First of all sorry for my English Its just an idea, like that "Intelligent Power Strip" but on the cheap. Use a relay powered from the PC molex (5v yellow-black), so that when you turn off your computer, it turns off, for example, the sound system, modem... connected to this. I have no experience with relays or high voltage. Anybody interested?

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forgesmith9 years ago

Dang I miss the old days when the PC power supply always had the old IBM PC type monitor plug/socket, all you'd need is the matching end, wire it to a power strip, and you'd be done.
NachoMahma9 years ago
. Your idea of using 5VDC (or 12) from the PSU sounds "safer" to me than using the parallel port, especially for someone without much experience. . Try to find a female connector (aux fans, &c or unsolder one from an old HDD) so you don't have to splice into your PSU wiring. Add a fuse/circuit-breaker, to protect the PSU. . Use a relay with a 5VDC (or 12) coil and contacts rated for 250VAC or greater at 15A or greater. Ratings are probably more than what you actually need, but will handle everything a duplex receptacle is designed to put out. Try to find a coil that has high impedance (low current draw).
javo. (author)  NachoMahma9 years ago
How about using solid state relays? its safer or draws less current?
Big Bwana javo.9 years ago
Solidstate relays are great, Most offer Optical Isolation, so your computer is only turning on and off a LED light sealed in a small cavity in the relay, and there is no Direct connection to the AC line, they also don't require kickback protection as no surge is generated when the fields collapse on a coil because optical relays lack coils, and you can get a huge amount of optical relays which have a 3 to 32 Volt DC input they have there own built in regulators, and they will easily switch a 15 to 20 amp 120, or 240 Volt AC load .. And they also lack contacts which burn over time, so they last longer....
. Yeah. What he said. . I forgot the clamping diode across the coil. :(
I only know that ..uhmm lets not talk about that, it was an expensive mistake involving a computer... ya keep the magic smoke in the chips and use a clamping diode or solid state relay.... (( ok I have to learn some things the hard way ))
I use large commercial use 6 socket power strips, they're great and have the advantage of having a neon lit switch for every two sockets, this makes them easy to remember and means you can for example hit one switch to turn off the computer and monitor... The other great thing is surge protected with heavy duty rated everything, along with being very sturdy, I did a pullup on one of them when it was hanging across a gap (the actual bar not the cable)
Big Bwana9 years ago
I think this is what your looking for, complete with pictures.. https://www.instructables.com/id/Computer-Controlled-Power-Switch/