Post by thread:Switching mains

Hi there! Has anyone out there experience with switching mains power (220v / 3amps) from a 12c508 ? (I'm trying to switch a PC ON and OFF) I'm trying to find a cheap but reliable method. I heard the cheapest method is using a triac. Could anybody give me a hint on what the wiring-diagram would look like ??? Thanx in advance. Max Dekkers,Netherlands

See the datasheet on the Motorola MOC3010, which should be available on the web. It includes some typical circuits. You may also want to consider just buying a Solid State Relay. These have either a triac or a pair of SCRs along with all the drive circuitry and opto isolation in a package. Harold On Fri, 1 May 1998 18:20:54 +0200 "Max Dekkers,ri" <spam_OUTMwa.DekkersTakeThisOuTnet.HCC.nl> writes: {Quote hidden}>Hi there! > >Has anyone out there experience with switching mains power (220v / >3amps) from a 12c508 ? (I'm trying to switch a PC ON and OFF) > >I'm trying to find a cheap but reliable method. I heard the cheapest >method is using a triac. > >Could anybody give me a hint on what the wiring-diagram would look >like >??? > >Thanx in advance. > >Max Dekkers,Netherlands > _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866]

On Fri, 1 May 1998 18:20:54 +0200 "Max Dekkers,ri" <.....Mwa.DekkersKILLspam@spam@net.HCC.nl> writes: >Hi there! > >Has anyone out there experience with switching mains power (220v / >3amps) from a 12c508 ? (I'm trying to switch a PC ON and OFF) > >I'm trying to find a cheap but reliable method. I heard the cheapest >method is using a triac. The cheapest method is usually an old-fashioned electromagnetic relay. They are also decently reliable and much more resistant to spike and surge damage than electronic switching. You will usually need a small transistor and diode to drive the relay from a PIC pin. Of course, if the application involves frequent switching, a relay can wear out. About 10,000 cycles over the life of the device seems like a good place to draw the line. _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866]

I use the Motorola MOC3041 + an external TRIAC for most applications where low voltage controlled mains switching is required. Its marvelous! Design effort is minimal. Duplicate basic circuit in data sheet (using larger TRIAC as your actual power switch and away you go. For very (very) light mains loads you may be able to use the MOC device alone with no extra TRIAC. Note the 15ma drive requirement. This is the worst case figure but whereas an opto may often be operated with far less than this, in this case they really mean it. eg 5ma probably won't work. The device is a zero crossing optically isolated logic driven triac made to drive larger TRIACs. Note implications of zero crossing switching on your application (in most cases this is what you will be aiming for but not in every case). Operation and circuit is super simple - See data sheets from Motorola (faxback) or elsewhere on web but BASIC details are as follows: Connect driver output (pin 4) to main TRIAC gate. Connect Driver out (pin6) via 51r resistor to TRIAC Anode. Connect resistor (330r) from TRIAC gate to ground IF TRIAC does not have internal resistor here (many do). Drive MOC input with at least 15ma (PIC pin can do this) (Pin 1 is diode anode = +ve. Pin 2 is diode cathode = -ve). RS sell these - part 301-628 (but they should be MUCH cheaper elsewhere). I pay under $NZ1.00 which is about $US0.50 in moderate quantities (50?). {Original Message removed}