Hi!
Can anyone tell me what is needed to change the design of Microchip's light dimmer (called PICREF-4) to use 220V instead of 120V?
Its no problem to change the program for the PIC12c508 - but I need the circuit to work with 220v @ 50Hz.
I really hope someone can help me.
Thanks in advance!
Best aRegards Zenty
the
Changing C3 to .065uF (65nF) should give you approximately the same current flow (~4.5mA). I would wait for others to comment on this before taking my word for it as I'm the resident idiot. ;-) I'll not bother to comment on the safety factor of this circuit other than to say that Phil will probably drop dead at the mention of this form of power supply. ;-)
"Zenty" schreef in bericht news: snipped-for-privacy@j33g2000cwa.googlegroups.com...
Hmm... Changing from 60Hz to 50Hz is a matter of software as you apparently know already. But changing to 220/230Vac is not that easy, not if you want to keep it safe and reliable. As a matter of fact I even have my doubts about the original circuit. One nasty spike on the mains may destroy the micro in spite of the surge absorber. Spikes on a 220/230V mains tend to be more destructive then on a 120V mains. A series capacitor will not suppress any spike of other HF-like disturbances.
If you nevertheless want to try, double R1 and R3, make C1 560nF and be sure it can handle both voltage and current. Use a type that opens when it fails. Take a triac rated for at least 600V.
I'd use a conventional power supply with a (very) small transformer and a
600/800V triac.No need to say it's all connected with the mains so it's dangerous.
petrus bitbyter
The voltage rating of C3 and Q1 needs to be increased. Use a L6xxx
600VDC part for the triac. For C1 you should preferably use a hefty capacitor rated for X-line service, not something from the POS series that was originally specified. RV1 should probably be increased to 250VAC operating voltage.Use two 10M 1/2W resistors in series for R3, and a 100 ohm 1/2W resistor for R1 and a 1/2W resistor for R2 (1M is okay).
The program also needs to be changed (maybe just MaxDim) but you know that.
The switches are electrically "hot" (meaning you need adequate creepage for your line voltages- say 8mm), this circuit is not all that robust, and you can easily hurt yourself if there is a mistake. Best get someone local to help you before you start applying power.
Best regards, Spehro Pefhany
-- "it\'s the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.