Add Shipping location + Iota weight and consumption


New Caledonia isn’t available in shipping locations when cart is completed. Can you add it? USPS Flat rate possible?

All individual product have weight in the description, except the IoTa.
Can you tell the weight of Iota alone? It will help to calculate the total shipping weight.

I might have to temporary monitor electric switchboard where no any AC power socket is available, nor easy to install.
Did you ever install ioTa on battery / off-grid source?
Any guideline of kWh/day needs to size the power source?


OK, added New Caledonia, we’ll see how that goes. Understand that flat rate shipping is slow. Have no experience with New Caledonia. Some countries take just a couple of weeks, others a couple of months.

The base unit weighs 6 oz.

IoTa can run off batteries (5V USB battery pack) but still requires a voltage transformer to measure electricity use. So you will need a plug.

Off-grid should be fine as long as there is an inverter producing AC power at a voltage supported by the power supply (100-240V) and the VT (I have 120V and 230V VTs)

Don’t understand this question.


Good point with transformer for voltage measurement.
Any option to not measure it and get thought with fixed Voltage value set with calculate variable, like EmonTX?

Question about Iota system average/max consuption was to size the battery attached to the small AC/DC inverter…

If no wifi nor internet connection is available on site, is it convenient to use a smartphone set to wifi hotspot?
I can then acces to Graph+ with a notebook or push data to local server installed on it.
If mobile internet coverage is available on my phone this could also be use to push weekly or monthy data to emoncms cloud?

No. The Emontx without VT only measures apparent power.

Can’t answer that one. 4 AA batteries will run the IoTaWatt for a few hours.

The internet is needed initially to set the time, and its good to check in periodically to reset the time and check for updates. Whenever WiFi is unavailable for more than an hour, the unit will restart. That doesn’t hurt monitoring, but isn’t recommended.

A smartphone hotspot will work.

Sure, but be aware that depending on theupload interval and number of inputs, uploading a week’s worth of data could take quite awhile.

Thanks. Your answer are really useful.

For a week, a 12V 12Ah battery sound not enought, better go to 12V 40Ah min.

How long can take a week’s woth data?
Let’s take for 5 sec resolution for 8 CT.
Of course internet 3G speed will be a hugde factor.
More likely 20 min? more than an hour?

Just to be clear, you will need to have a VT that is connected to the same power source that you are trying to measure. So if you are placing CTs on circuits in the switchboard, you need a CT plugged into one of those circuits.

You asked if IoTaWatt can be used off-grid, and the answer was yes, to measure the power used by the off grid system. You can’t measure power from the grid using a VT plugged into an off-grid inverter.

I can’t estimate the upload times. From what I can see NC is connected to the world through Sydney. Australia is a long way from the UK where the Emoncms cloud server is. Data usually goes the other way to the US and then to Europe. Unless the data will be used elsewhere around the globe, you would be better off with a local RPi or other instance of Emoncms.

My bad, I get confused when you did mentionned than Iota can last a few hours with AA batteries. Are you sure there is no way to only measure amperage without voltage reference?

I can set a RPi as an local hotspot, but I’m still afraid of setting an local intance of emoncms as I don’t have linux based machine. Wich solution for is the best option for windows enduser?

I might just acces to web based Graph, Grap+ and then import Csv file for excel post treatment.

I’m sure. Not with IoTaWatt.