Emontx power consumption

Hello Everyone,

I am new to the Emonpi data logger and i want to use emonpi energy monitoring system in rural area to analyze how much power is consumed by local residence while using cooking food by an electric device such as induction cooker or low power cooking stove where power is supply from 60kW micro hydropower for 3 phase.
Can you please provide me information, how much power is consumed by EmonTx while connecting with 1 CT sensor and 1 temperature device. As i have only 20kW total power generation capacity in a single phase for a small village so i have to analyze , how many households should i install EmonTx devices without distributing their day to day electricity supply.

Thanks in advance
With Regards

I don’t think anyone has actually measured the power consumption of the emonPi and emonTx. I would say don’t worry, it will be too small to consider. However, you can try to estimate it.

The emonTx draws approx 10 mA normally and about 55 mA whilst transmitting, from an 11.6 V
supply. As it transmits for a few tens of mS every 10 s, let’s say that is 150 mW. To that you must add the losses in the a.c. adapter. The efficiency is quoted as 80%, but that will be at full power. I would guess a total of around 200 - 250 mW for each emonTx.

The emonPi is a Raspberry Pi with an emonTx added, but it doesn’t transmit in normal use (only when you have an emonGLCD). Therefore to that 150 mW, you add the power consumption of the RPi. Again, I have not measured this, but I’ve read it’s about 0.5 A at 5 V, so 2.5 W, again you must add the losses of the 5 V power supply, so say 3 W. This is entirely credible as the ‘shop’ power supply is rated at 6 W, and it runs happily on that.

You would need quite a few emonPis to make a significant impression on a 20 kVA generator.

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Dear Robert,

Thank you for your response, it makes me easy for further power calculation