Generic VT - parameters?

Hi, a new user here.

I am going to order a IoTaWatt generic kit only to monitor electricity consumption in my house. However, as I live in Czech Republic (EU), none of the recommended 230V VTs are available here and importing it from UK is quite costly. I would like to buy a decent 9V PSU.

Question 1 : I didn’t find any specific info, whether it has to be a stabilized power supply (with transformer) or I can use a good quality switching power supply instead? Also, what minimum current is OK? I read in the help section that it draws only 0,4mA which is close to nothing - is it true? As for the calibration, I can do it myself then.

Question 2: I can only get SCT-013-000 CT, which I understand is quite acceptable, is it ok to use it?

Thanks a lot!
Regards, Ondrej

The VT is a nominal 9VAC transformer. You are describing a DC supply. I would recommend you spend the money to get the Ideal supply from the UK.

IoTaWatt does also need a 5VDC USB power supply but you can order that with the IoTaWatt.

SCT013-000 is supported, but be sure it’s not one of the counterfeits widely available and that it has 50mA output.

Thank you very much for the clariffication. I must have missed the AC/AC transformer speciffication. I will look for similar transformer here. I am afraid that the shipping costs from the
Uk will be double the price of the transformer itself.
As for the 5V DC, I have a 2amp PSU from my Raspberry PI which I can use.
I will purchase the SCT-013-000 in local electronic shop, they sell the originals.

So for now, I only need to find the 9V AC/AC transformer.

Thanks again, Ondrej

While IoTaWatt only uses < 1mA, small transformers will have a lot of phase shift and would need correction for best results. The rule of thumb is heavier is better for low phase-shift. The Ideal is quite heavy and that’s part of why shipping is expensive and why I don’t sell them for international shipping.

Thanks a lot. I decicded to order it from UK (OpenEnergyMonitor) even though the transformer price is 9 GBP and the shipping is 13 GBP. I was not able to find similar in local shops. I also made order of the IoTaWatt unit, looking forward to set it up soon.
Happy new year!
Regards, Ondrej.

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