I'm looking for a small LED indicator that I can use as part of a sign, basically turn on the LED bulb when certain conditions are detected by HE. Preferrably small enough to run from battery and be hung on the wall as part of a kitchy sign.
Anyone know of one, or a simple way to hack something?
There are very few battery powered devices that receive commands. This is because most battery powered devices essentially turn off their Zigbee or Z-Wave radios until there is some data to send to the hub. If they leave their radio on, it dramatically reduces battery life.
Most battery powered devices are Sensors, such as contact, motion, water, temperature, etc... They use an ultra low power mode to wake up based on either a time based trigger (like to poll for a new temperature value) or an event based trigger like a magnetic reed switch. When they wake up, they collect environmental data, and then transmit that data only if it has changed significantly enough (or if enough time has passed since the time they last sent data.)
If using a mains-powered device is acceptable, many more options will be available. The simplest device to implement would be a Smart Zigbee Color LED light bulb. If you want something smaller, and you’re not afraid to build something, you could use an ESP8266 (WiFi) plus an LED running my HubDuino software.
This looks really cool. I've been building up courage on the Sparkfun site all day. One thought was to get the Motion sensor with the LED light that's changeable, and let it wake up when it senses motion/presence nearby... then check for conditions on the hub, and hold the LED on for a few seconds to inform the passerby of status.
Thanks for the insights on the wake cycle. I hadn't fully burped that thought.
There is one battery powered Zigbee/z-wave device that might suit you needs. There are numerous battery powered sirens available on the market, some with LED “strobe” lights. You might need to hack one of these devices to suit your needs, but it has the advantage of being packaged already for battery usage.