Real time display

I am looking into purchasing the IoTaWatt for monitoring my home power, generator output power and future solar. I have a question about the information that can be displayed in real time or near real time. I plan to have EmonCMS be setup on a spare Raspberry PI and using a tablet pull from that to display power usage. I see the IoTaWatt does get the frequency (60Hz), but I wanted to know if it can show frequency changes, like say 59.9Hz. I need that more for my backup generator output. If it can show that does it send that information to EmonCMS for Real time display? Or is there another way to output that? I don’t mind say a 1 second delay even with that, it’s just more for the geek engineer side of me.

IoTaWatt can send data to Emoncms at 5 second intervals. You can send AC frequency to Emoncms with a value to 2 decimal places.

The Emoncms dashboard visualization tools allow real-time update.

There is also the IoTaWatt’s native status display that updates every second. The frequency displayed is to 1/10 Hz.

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Sounds good. What would be my options for displaying the IoTaWatt’s native display on the wall?

Probably a tablet. Make sure the browser works with IoTaWatt. I’d look at android.

I’m in the process of building an ESP8266 based display for my home as I have more data than I need in the browser. Using an ESP8266-12F module and a 4-line LCD display, I will display power [w] (home, solar, grid). Delay 5-seconds, clear the display and put up energy [kWh] for the same three and wait 5-seconds. Lastly, display some misc items such as solar radiation [m/2], grid cost [$], and voltage [v], then query the data from EmonCMS again; rinse and repeat. It will be near real-time as the cycle of the three displays will take about 20-30 seconds before getting the new feed data.

Just wanted something small and portable (due to the many queries and backlight it needs to be plugged in), and small. Just finishing up the coding but have it about 70% done. Overeasy is correct if you want to display all the data, it might be simpler to pick up an inexpensive tablet to use. The Raspberry Pi screens are too expensive for what you get. That is why I went with a cheap LCD display.

Thought I would show you my early display project. I will be putting it in a case and a power cord. But, this is so you can see what you can do with the EmonCMS API and a few parts. Sorry for the poor quality of the third screen. You can retrieve any feed from all your EmonCMS data. I have both IoTAWatt and weather data (Temp, humidity, pressure, solar radiation, etc.).

It is later in the day and the sun is nearly down, but you can see we did ok for a cloudy day with 31kWh generated by our solar panels.

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That actually would work perfect for what I’m thinking. Thanks.