A couple of customers asked me what to do when the Chromebox, which we use for Chromebox digital signage, “goes to sleep” or actually enters some sleep mode (or like hibernate mode in Windows OS) after I turn off or disconnect the attached screen for some time. Well, first thing to know is that it won’t enter the sleep mode immediately. It will take some time. How long? That depends in the certain Chromebox which you have (and there are several types of Chromeboxes in the market).
Caffeine and Keep Awake Chrome extensions
 

 
The first thing you can do is to put your Chromebox in Kiosk mode (if you have a Chromebit instead, consider it as Chromebit Kiosk mode). You can do it when your Chromebox is a non managed device and of course when your Chromebox was enrolled into Google’s Chrome Device Management (which gives you a lot of other remote management options, but costs you an annual license).

Usually, when it comes to Chrome OS digital signage, you will prefer the Kiosk mode as the signage player should run 24/7.

However, what if you do not put it in Kiosk mode? For that, there are 2 recommended apps which can be downloaded from the Chrome Web Store. The first one is called “Caffeine”. It’s plugin or actually an extension for the Chrome browser: https://chrome.google.com/webstore/detail/caffeine/miadkhnklmfgdcoibbjfmdnljfkbhlng?hl=en
The second one is called Keep Awake. It is also a plugin: https://chrome.google.com/webstore/detail/keep-awake/bijihlabcfdnabacffofojgmehjdielb?hl=en
If you have some time, you can also read this article.

May the digital signage force be with you.
Nir.