Questions tagged [power-meter]
The power-meter tag has no usage guidance.
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Energy meter, automatic line frequency detection
We are designing an Energy meter based on ADE7816, we put line frequency as a programmable parameter, which will be entered by the operator, Is there any way to automatically detect the frequency ...
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How does a power meter differentiate between three-phase and single-phase loads?
How does a three-phase power meter (for example the one used by my power company) know the difference between a single three-phase load and multiple single-phase loads?
For example: a three-phase ...
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Why do treadmill amperages fluctuate? [closed]
Multiple sources describe monitoring a treadmill’s current as an indicator of friction. When it increases, it’s time to add silicone oil between the deck and the undersurface of the belt. One good ...
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Power meter design
We want to design a 3 phase power meter that measures AC voltage, current, frequency and calculates power factor.
We want to use a voltage transformer and a current transformer for each phase.
My ...
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Need to understand the current sensor connection in this circuit
I'm working on creating a smart power meter for my home, and I found this tutorial. I want to understand each part of the circuit, and the tutorial covers everything. However, it doesn't explain why ...
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What is I2C address of ADE7878?
I am working on 3-phase power meter development.
I designed the hardware using ADE7880. But due to component shortage, the lead time for purchasing ADE7880 was 2~3 weeks. So I decided to use ADE7878, ...
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Off grid solar PV performance analysis
I need to compare a single axis solar PV tracker system with a fixed tilt solar PV system for how much power produced in 1 day or 1 week or 1 month. Both systems will be off grid. What kind of load do ...
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Current transformer variable burden resistor for wider current range
I want to use a current transformer to measure a 100A AC supply (240V domestic incoming supply) with a minimum current of 1mA, with essentially an Arduino. That seems quite a tricky brief so my ...
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Why 7 dB power increase after combining identical strength signals?
I have signals from two transmitters that are combined via a power combiner (link).
Both signals are at 7 dBm when fed into the combiner on their own. When combining both, the meter either reads 7 dBm ...
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Possible problems of AC energy metering using rectified waveforms
I'm building an energy metering circuit with discrete parts and precision is not a big deal in this case. One friend had the idea of rectifying both the voltage and current waveforms before sampling ...
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What do the stars in a power meter symbol mean?
Sometimes I see stars in a power meter in three-phase circuit are drawn as below.
What do the stars in a power meter symbol mean?
There is another example here (page 14/20):
Now it seems to me that ...
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Red laser that has a higher power output at 400nm than 623nm?
I am doing experiments using a red (623nm) LED. However, when I measured the power output I noticed that it is higher at smaller wavelenghts. I did the measurements using two different power-meters ...
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Can you prove that electricity was generated by a photovoltaic cell?
I am wondering if it would be possible to build a photovoltaic cell that kept track of the electricity it generated (perhaps with a built-in meter), such that you could not trick the meter without ...
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How can Kill-a-watt show .1A, 12VA, but 0 watts?
I'm trying to verify whether a 10W aquarium heater is failing. It has a safety fuse that renders it permanently inoperable if it overheats by running unsubmerged, which is suspected in this case. My ...
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what is the electrical component symbol in datasheet ABB M1M 10
I am planning to install a power meter ABB M1M 10 with Delta connection (2E) 3 phase 3 wire system. However, I fail to recognize the electrical component symbol in the red area of the attached image ...
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What device can I use as a load to calibrate a power meter accurately?
In old times calibrating a power meter was as easy as connecting 1x, 2x, 3x high power halogen bulbs to get realistic data, free of reactive power or strange waveforms with strong harmonics.
Nowadays ...
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My first full contact-less power meter doubts
I need to measure power consumption of an industrial machine, it is supplied with 3-phase plus neutral connections, 220V per phase. They said there is a voltage stabilizator device between the power ...
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How Power measured by Meters is affected by Harmonics?
I want to know how energy meters (Electro-static or electronic) measure Energy (let's assume power, ignore time) when there are harmonics present.
I know what are harmonics, how are they generated ...
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DDS238 AC Power Meter: how to calculate current power consumption using pulses
I have a DDS238 AC power meter with 2000 pulses/KWh (1p/0.5Wh) and I want to calculate the real-time power consumption and play an alarm if the value exceed a specific value.
I'm using an ESP8266 by ...
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RF Power Meter vs RF Power Sensor
What is the difference between a power meter and a power sensor?
If I got this right a power meter is the instrument that reads and displays the measurements of the power sensor. Also, power meters ...
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Safety precautions when developing and testing mains voltage devices [closed]
Specifically, I am planning to design and build an energy meter to measure power drawn from mains - 120V 60Hz.
What are the risks associated with developing and testing this device and how to minimize/...
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ATM90E32 total energy reading
I'm developing a simple power meter using the ATM90E32 from Microchip. For now, I can read all values: frequency, power factor, voltages, apparent power, etc.
Now the issue is with the energy, I need ...
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Whats the purpose of 0R in Sonoff POW [duplicate]
I'm designing my own Sonoff with ESP32, with power monitoring capability. Now before I start my own design, I took a look at Sonoff design. In the Sonoff POW the power metering IC has a 0R resistor, ...
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How make a pulse acquisition from an electrical meter directly into a raspberry pi?
I would like to acquire pulse informations from a french electrical meter.
There is a picture of the outputs of this electrical meter.
These pulses vary in frequency and after acquisition, we can ...
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Fake energy saver inductive loads
I watched this video on YouTube, it covered fake energy saving devices.
I have seen many of these fake devices and they all seem to use a capacitor. My question is why would they bother? The person ...
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How to have Wye-connected Potential Transformers(PTs) and Neutral Ground Resistor short circuit detection at my ground fault protection relay?
Detecting if the Neutral Ground Resistor (NGR) is shorted is something that must be checked at the Ground Fault Protecting Relay. The typical way to do this is to inject a DC component and to measure ...
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What is the 'right' way for a 3-Phase Watt Meter to determine import-export Watt-hours?
What is the correct way for a 3 Phase Watt-Hour meter to measure total import/export watt-hours?
I ask because I have seen this done in 2 different ways both in 'approved' meters:
Assume that:
Red ...
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How does a Hall-based wattmeter work?
I read about the Hall effect and understand its usage in sensors like speedometers, but I also read it can be used as a wattmeter. How can it happen?
In order to calculate power (P) we need to ...
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3 Phase Energy Meter to measure multi channel
Can I use single 3-phase energy meter to measure multiple 3 phase load using multiplexing relays for the CT outputs?
For example like below picture.
The intention is to log data for multiple 3-phase ...
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RS485 registers for calculating total power consumption (kwh)
I have an energy meter (OHIO A2000) which has been now discontinued by the manufacturer. Anyway, I'm following the manual for extracting energy parameters through Modbus RS485 communication. I'm ...
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Power meter current transformer: possible to sum mutiple phases
I am currently looking at this inexpensive power meter modules with TTL interface.
It seems to use internally the same ASIC as many chinese wall-wart power meters: It comes with a current transformer ...
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Micro Watt Meter in Extreme Low Temperature [closed]
I'm using a solar panel in the Arctic and I want to measure the power it delivers to the associated sensors. Is there any recommendation on a watt meter for this environment? The temperature is ...
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How many disc revolutions make 1kWh on this kWh-meter?
This a kWh meter from a TV show. I'd like to know how many disc revolutions make 1 kWh. I think it's somehow coded in the whole data on the panel or could be derived from that information:
I found a ...
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How To Calculate kVA values in power analyzer meters?
I am using a Schinder Electric PM2120 power analyser meter.
I record values with it every 15 minutes.
When I calculate values in kVA manually and compare them with the recorded values, I notice that ...
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How to read maximum input [closed]
This is Carlo Gavazzi Power Analyzer, the sticker says
Input 3x380(660)V
Does it means that the maximum input voltage per line must be 380V or 660V?
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Can we assume 230VAC in 3 phase system between phase and neutral?
If all devices connected to a 400V 3 phase power system are balanced and have a perfect power factor, can we assume the voltage between each phase and neutral is 230V?
Why: I want to measure real ...
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Ammeter show half of the real current draw [closed]
I have a couple of ammeters from China, they have 2 connectors:
Con 1: Yellow voltage sense, Black and Red to power the ammeter.
Con 2: Thick Red and black for current sense.
They are designed to ...
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Can a power board impact watt meter readings
I've just measured two different but conflicting readings using an off the shelf watt meter. My quandary is that these measurements conflict and seem untrustworthy.
My question is: whether measuring ...
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Challenges of Power Line communication
I am looking into Power Line communication (PLC) as a means for smart metering. It looks totally possible to send the data from the meter to the source of the power supply or the transformer.
Most of ...
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Questions regarding a micro-wattmeter
Whilst looking for test rigs to experiment with tuned circuit filters, I came across the following article (http://www.robkalmeijer.nl/techniek/electronica/radiotechniek/hambladen/qst/1991/12/page29/...
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What is the role of shunt in a Power Meter?
I just got a PZEM-051 Power meter and I can see that in order to measure the power, one needs a shunt. At least that's what I can see from different YouTube videos and I was wondering why would I need ...
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What do the specifications of this RF power meter mean?
I am looking for RF power meter to measure the output power of RF based PCB board which is estimated to give an output power of 45dBm at 868MHz.
While searching for meter I have come across ...
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Atmel M90E26 energy meter
Datasheet
Application Note
I'm working with the atmel m90e26 IC. Its energy is numerically pulse_based, but I do not know what the relationship between energy and pulse is in this IC. There's a ...
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How does a bi-directional electricity meter know import from export?
I've searched everywhere for this but can't find the answer...
Its possible to have 3 phase electricity meters that measure both imported and exported kwh with each value being recorded in separate ...
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Reactive energy: forward and reverse components?
I'm trying to figure out how to measure energy consumption with a power meter.
It reports for the three phases:
Total Active Energy
Forward Active Energy
Reverse Active Energy
Total Reactive Energy ...
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Need help interpreting a Energy Meter datasheet
I am reading this datasheet for an energy meter, to start understanding how this market works.
A friend of mine wants to make a test in a small office building to see if it pays having one of these ...
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How to partially drive a load with respective impact on my electricity meter?
I want to optimize the use of my photo-voltaic production by redirecting the remaining unused energy to electric heaters in winter, or something else in summer (given that fans are inductive loads and ...
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How to turn a PLC smart meter into 3G or Wifi [closed]
My utility has deployed bout 300,000 ZX E221 Three Phase Prepayment Smart Meters and they consist of a Meter control unit (MCU) which the consumer cannot access and a User Interface Unit (UIU), which ...
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Protection of Energy Meter from 35KV spark
I have been building a prototype of an energy meter for a project. One of the aims of the project is to make sure the energy meter can withstand a 35KV Spark applied to it.
I was wondering how this ...
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My IC keeps blowing up - PAC1720 current sense IC
I am using a PAC1720 current measuring IC to measure the current/voltage/power being delivered to a lead acid motorcycle battery that is being charged.
Here is a newer datasheet and an older datasheet ...
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