# How does a 120VAC neon indicator lamp respond to a leading-edge triac dimmer?

I bought a dirt cheap toaster oven to convert to a solder reflow station, and I noticed in the teardown that it apparently has a neon power indicator. It goes out instantly when it loses power instead of fading like an incandescent, and it measures open-circuit when off.

I'm not opposed to cutting it out of circuit, but I also thought it might be nice to have a rough indicator of what it's actually doing, if it actually works that way.

Here's the circuit:

simulate this circuit – Schematic created using CircuitLab

So:

• Does it "just work" and produce an incandescent-like end result?
• Can it confuse the triac? (probably not because it's in parallel with the resistive heater and my software is going to hold the opto on anyway)
• Is there something else I ought to know about using neons and triac dimmers together?

• Even though it's a heater with relatively slow response, I was planning on actually dimming it instead of just on/off. (The software will operate as "phase-locked PWM" at 120Hz.) Given a ~100k series resistor in the neon, I agree in that I can't see how it would affect anything except itself, but just out of curiosity, what would the neon do with that? Would it have more of a threshold behavior? Just off if it doesn't receive the strike voltage, and just on if it does, with some flickering around the threshold? – AaronD Oct 13 '17 at 15:04
• Okay, so it sounds like my prediction is correct then: on like usual above ~40% power (just a guess, but definitely <50%), off below ~30% (another guess), and flickering in between. Thanks! – AaronD Oct 13 '17 at 15:54