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This circuit will automatically switch on several mains-powered "slave" loads when a "master" load is turned on. For example, it will switch on the amplifier and CD player in a stereo system when the receiver is turned on. It works by sensing the current draw of the "master" device through a low value high wattage resistor using a comparator. The output of that comparator then switches on the "slave" relay. The circuit can be built into a power bar, extension cord or power center to provide a convenient set of "smart" outlets that switch on when the master appliance is powered (turn on the computer monitor and the computer, printer and other peripherals come on as well). |
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| what is the value of R2 and R6, when we want to use 240v as the supply???urgent... | ||
| ohms law , would indicate half the resistance , not double and it would be 4 times the wattage(power dissapation---...---...---...G.R.. . . . . | ||
| Ohm's should tell you that if you double the voltage in, and you want the current to stay the same, double the resistance. This will also double the power dissipation of the resistors. | ||
| when used at 240V. What need R2 & R6 to be. // Morten | ||
| The values of R2 and R6 need to be CHANGED if you are in 240V like we are in the UK. Again, what is the value or formula for R2 & R6 please? | ||
| What is the Values of R2 & R6 (Editor's notes: Try looking at the parts list.) |
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