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can the transister be used to switch ac voltage? Answered

hi , i am controlling 4 el wires using basic stamp.
 i am using an inverter that outputs 6v dc to 110v ac.the inverter has 4 outputs to connect with el wire. can i use a transister as switch? lot of people use triacs.i am not sure whether transister can switch ac  voltage.thanks



Using TRIACs are the way to go. Drive the TRIAC via an opto-coupler, say an MOC3021 or similar. You could use relays but that is a bit messy.

For the kind of current involved on the HT side, the MOC3021 will probably switch directly. They'll switch 50mA quite happily, and 100mA if ytou can keep the temperature down !


Although this doesn't answer the question directly, unless you intend to individually switch the loads, it would be more logical to simply switch the input side, both in terms of energy conservation and cost.

Seconded - if you don't need high frequency switching - then switch the power to multiple inverters...or use triacs as others say.

or igbts or some fets... I'd still be inclined to use a simply dc opto relay and if possible, drive it directly from the arduino or thru a buffer chip. I didn't see anything on load current, but I've used dip package optofet relays that drive up to a couple of amps without any issues whatsoever @ ~$5-6 unit price from mouser and digikey. simple to use, nice loading, and small as sin.

A transistor cannot switch DC directly, no.