Post by thread:[OT]: Truly green PC?

There's an interesting idea I saw in the Elektor magazine. When a PC (ATX SPMS) switches off, or hibernates,, the monitor still keeps consuming some power. Now, in this situation, it seems the +5V on the game port switches off as well. So, drive a relay by this voltage, and power up your external peripherals like the monitor, printer, mains powered speakers etc. thru' the relay contacts. A truly green PC! My question is, what is the maximum current one can draw thru' the 5V available on the game port? Regards, Anand Dhuru -- http://www.piclist.com hint: To leave the PICList spam_OUTpiclist-unsubscribe-requestTakeThisOuTmitvma.mit.edu

On Tue, 2002-02-05 at 14:44, Anand Dhuru wrote: > There's an interesting idea I saw in the Elektor magazine. > > When a PC (ATX SPMS) switches off, or hibernates,, the monitor still keeps consuming some power. Now, in this situation, it seems the +5V on the game port switches off as well. So, drive a relay by this voltage, and power up your external peripherals like the monitor, printer, mains powered speakers etc. thru' the relay contacts. A truly green PC! > > My question is, what is the maximum current one can draw thru' the 5V available on the game port? > I have just done the same thing, but used the USB port. The solution I adopted was one designed in an Electronics Magazine (don't remember which). This is really simple: MOC3021 + Triac. I was worried that the Triac would get hot, but the unit powers my monitor, speakers, laser printer, hub and a few other odds and sods without getting hot and without a heatsink. The circuit is trivial - one current limiting resistor into the DIAC and an RC snubber network on the triac. Works fine for my piddly non-inductive load! I don't have the data sheet for the opto isolator here, but I'd punt on only 20ma or so drain on the USB. Of course, if you DO plan high power devices the TRIAC power dissipation could be a very serious problem.. /Kevin -- Kevin J. Maciunas Net: .....kevinKILLspam@spam@cs.adelaide.edu.au Dept. of Computer Science Ph : +61 8 8303 5845 University of Adelaide Fax: +61 8 8303 4366 Adelaide 5005 SOUTH AUSTRALIA Web: http://www.cs.adelaide.edu.au/~kevin Fingerprint = 7E5A A0C2 22BC 5993 17F2 93CE B1FD DEC6 D0C0 50CD -- http://www.piclist.com hint: To leave the PICList piclist-unsubscribe-requestKILLspammitvma.mit.edu

> how much current on game port You can draw 100+mA without problems but do not feed back ANY spikes or pulses into that line (as caused by arcing contacts etc). Cheap ports have no protection and you can draw the max PSU current from them (50+A) for the first few miliseconds (after that it does not matter anymore). Better ones have a polyfuse or a chip protector there. Peter -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics