This device is a digital watt-meter allowing you to monitor the power consumption of electrical devices. Its works with both AC and DC current. Regarding AC current, the device computes the real power consumption (not just the product of RMS voltage and current), so it can be used to monitor inductive loads. The Yocto-Watt can compute the power consumption during a given lapse of time. Accuracy is 1mWh, 1%.
This device is isolated, which means that the sensor part is electrically disconnected from the USB part: you can measure any voltage difference between -250V and 250V, without risk of frying your computer. The module provides immediate reading on USB and can also store measures on the device internal flash for later retrieval when connected again by USB.
This device can be connected directly to an Ethernet network using a YoctoHub-Ethernet, to a WiFi network using a YoctoHub-Wireless-n and to a GSM network using a YoctoHub-GSM.
USB cables and enclosures to be ordered separately.
Currently, I'm planning to buy YoctoWatt to monitor all the wattage in my house. I subscribe for 2200KWH.
Will this thing work ?
@funky81: actually the 22000kWh value is not sufficient to answer: is it per month? The decisive parameter is the Amp peak. The Yocto-Watt limit is 16Amp. Note that at 16 Amp continuous , the shunt on the board will get pretty hot (~100░C). Beyond this limit, the device will become a fire hazard.
So I wouldn't use just one single Yocto-Watt for the whole house. I would use, lets say, one Yocto-Watt per circuit, and I would make sure they are properly cooled.
Also note that Yoctopuce devices are not certified (see Yoctopuce's General Terms & Conditions).
Yup, thats 2200KWH per month. Currently, my house current stable at 7.8Amp.
Since this below 16Amp, will it be sufficient enough to use this product?
Anyway, let me check how many circuit my house have.
@funky81: With 7.8Amp avg you seem to be the safe side. Nevertheless you still need to check for peak consumption. Install your Yocto-Watt and switch on as many big equipment as you can. Check that the total consumption is below 16A. You also need to make sure the Yocto-Watt temperature stay reasonable. DO NOT touch it to check, use a infrared-thermometer or install a Yocto-Temperature in the same enclosure.
I'm looking for some indication of the storage capacity and the interval the values can be stored. What place can I find this?
@blacksmith: You can find this in the user manual, Chapter 19 section 2 (see http://www.yoctopuce.com/EN/products/yocto-watt/doc/YWATTMK1.usermanual.html#CHAP19SEC2 ). The Wattmeter can store up to 500'000 measures. Since each data sample stores 5 measures (DC voltage, AC voltage, DC current, AC current and power), it means you can store 100'000 data samples.
I have a Solar Charge Controller and I'd like to see how much output my PV (12v 40W) is providing, what my draw on the load is and what capacity my battery is at.
To do this, would I have to purchase 3 of these units, or is there a better product?
@RB: One single Yocto-Watt can do all this at the same time.
@martinm How is that possible as there is only a single Input/Output?
@RB: There might be a little misunderstanding here: The Yocto-Watt can give the Voltage, Current, Power, and perform Power integration on a electric connection. If you need to monitor several connections, you will need several devices.
Hello i need scan instant power comsuption to motor 0,5 kW 230V every half second. Would this work with Your Yocto-
@ jirkasi: Yes, that should be no problem
I have to measure AC loads which peak 50A. May I use a current transformer, as with other instruments?
@southerner: you can use a current transformer, but be aware that CT will add a small phase shift, which will slightly alter the measure of power. A good CT has a phase shift of only a fraction of degree, which will have no significant impact, but a cheap CT may have several degrees of phase shift.
Hi, I would like to measure the power consumption of a mobile phone and of a single board computer (Odroid), would the Yocto-Watt be good for this application? I used an ammeter before inserting it in between the phone and the battery, but I would like to obtain power measurements
@mmoram Yes, that is a typical use for this product
I'm needing to measure three phase power. From the user manual it looks like it's just single phase, would I need three units for this?
For 3 phases power, it would make more sense to use a power-meter like the one we used here: www.yoctopuce.com/EN/article/monitoring-tectrice-consumption-over-gsm
Calibration doesn't seem to work for data retrieved from the logger?
@markb: Yes, it works also when retrieve data from the datalogger (if it does not, it's a bug!). Note however that when retrieving data from the datalogger, the calibration is applied by the API code: calibration parameters are loaded from the device, and applied to each raw measurement retrieved from the datalogger before returning it.
Looks like a bug in the API then. I see the exact behavior you describe when I read results directly. But not with the Data logger.
@ Mark Brown: I think we should continue this discussion by email. You can send an email to firstname.lastname@example.org.
Also in this email could you precise which programing languages you are using and which version of the Yoctopuce library you are using? It could also help if we can have the part of the code that retrieve measure form the datalogger.
Is this discontinued or it's temporary unavailable?
@pmladenov: it's just temporary: a customer bought the whole stock :-) we had to reorder some parts :-(
Hi I'm relatively new to DOI projects and coding it self.
Now I'd like to communicate with the Yocto-Watt, that is connected via USB micro type b to a Raspberry Pi 3B+ and should be controlled via CLI. My question is:
- is this possible?
And if so:
- Are there any projects done in this area yet?
- or can some one give me a gentle nudge in the right direction?
@amma: sure, you just have to use the Command Line library from www.yoctopuce.com/EN/libraries.php . You can find a general description here www.yoctopuce.com/EN/article/new-command-line-api and some Yocto-watt related exemples in the Yocto-Watt User manual.
Hi can anyone tell me if the watchdog function at the YoctoWatt is equivalent to relay and if so, can it be used to stop the energy transfer for more than just a moment?
HI can anyone advice me on how to proceed?
So my situation is that:
I would like a raspberryPi to host the yoctoWatt and listen via a website to a blockchain and if a specified situation occurs the pi shell start to measure and store the data.
So what is the recommended approach here?
I have though about having the pi host a local website and use the VirtualHub to post the data on some website but im not certain how that works or if there is another approach more favourable?
Many thanks ahead.
@amma: there is no Watchdog feature on the Yocto-Watt. Since you are using a Raspberry PI, you can do what ever you want, like using the VirtualHub to post Yocto-Watt data on the server of your choice or using your favorite programming language and our libraries to build your own solution. If you need help with that, just contact Yoctopuce support directly.
Hi, I'm starting to use Yoco-Watt, and I would like to measure the energy consumption of my computer, but I didn't know how to make the connection.
Can you please tell me how to do it or can you make a youtube video showing how to do it?
Many thanks ahead.
@serdan: You will find a diagram in the user manual section 2.2. But honestly, if you are planning to monitor a mains powered appliance, but don't know how to connect it, you should ask a professional to do it for you. Wiring mistakes could kill you and/or burn your house down to the ground.
@martinm thank you for your reply,
I will consult a professional for the connection. However, I just want to make sure that the sensor is suitable for such an experiment? (measure the consumption of my computer)
@serdan: Yes, the voltage and current consumption of a typical computer is in the operating range of the Yocto-Watt
I have two questions please. How to connect Yocto-Watt in three phase line? Are there any multichannel boards available?
@irfan : The Yocto-watt is not designed for 3 phases systems. If you have to measure such a system have a look here: www.yoctopuce.com/EN/article/monitoring-electric-consumption-over-gsm
I am yet to receive the device. My research will involve using the data generated to analyze for trend in power usage in a computer for different apps/tasks. Since I have not used this before, I would like to see an sample/example of the output from the device? Can you help me with a sample data generated on a laptop/computer please?
@gsel : since you are supposed to write your own code to extract data from the Yocto-Watt, there is no typical data output format. You will find a programming example dedicated to the Yocto-Watt in each programming libraries (www.yoctopuce.com/EN/libraries.php).
If programming is not your thing, you can use the VirtualHub (www.yoctopuce.com/EN/virtualhub.php) or Yocto-Visualization (www.yoctopuce.com/EN/tools.php) to export data in CSV format.
While waiting for your device to arrive, I suggest you have a look at our tutorials section (www.yoctopuce.com/EN/tutorials.php)
Thanks, I used the virtual hub to start with to extract data from wattmeter.
This is the output:
UNIX time ISO time power voltage1 voltage2 current1 current2
1652139318 2022-05-10T11:35:18.000Z 0 -0.001 0 0 0
1652139319 2022-05-10T11:35:19.000Z 0 -0.002 0 0 0
All values are zero or negative. I plugged it into the USB console of my laptop. Please let me know if I need to do this differently.
@gsel: negative values means you have either a polarity or power/load inversion in your Yocto-Watt wiring, see
Contact Yoctopuce support directly if you need more help.