Another type of SSR, called a ‘random turn on’ solid state relay, is used to implement dimming ... or extended periods of time. My mains wiring does not include an electrical ground.

But what if all you have on hand is an ESP8266? [TechColab] needed to control a solenoid valve with a short pulse via a solid-state relay (SSR) but found that the trusty 555 timer was tricky to ...