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Best Way To Switch A 5A 120v Inductive Load

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I have a ballast (inside is a transformer, no other parts) for a light that is rated at 4.6A @ 120v that I would like to be able to control with a micro. I have a feeling that it draws more current than that when it's warming up, so Ive been searching around using 8A as my required current. What is the best way to control it? The ideas Ive come up with are a mechanical relay (afraid of any possible arcing at high-amperage), solid-state relay (kind of expensive Ive found), or some type of MOSFET or IGBT (or perhaps a TRIAC? I have no experience switching AC loads using anything other than a mechanical/solid-state relay).

What would the "best" option be, and why? Id like to do it for the most reasonable cost (not necessarily the cheapest) but Id also like longevity - I dont want to have to replace a mechanical relay or FET every month or two.


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The best way is likely a solid-state relay. For controlling AC they generally consist of a Triac, an optical isolator (which you need for safety), and a zero crossing turn-on circuit (for low EMI and surge current). You could try building something like that yourself but it probably would cost more than just buying one.
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