Questions tagged [power-measurement]
The power-measurement tag has no usage guidance.
100 questions
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ACS71020-I2C data read problem
I recently working on ACS71020 with I2C communication .I will attach my module details, code and my results. The slave address of the I2C keeps changing and even If I turn on the supply the measured ...
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RF jammer module power measurement using a spectrum analyzer
I have an RF jammer module that works at 2390-2510 MHz. The voltage is 24-28 V and it can transmit up to 50 W.
When I use a spectrum analyzer, the value is around -20 dBm. If I'm not mistaken, -20 ...
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Yokogawa WT3000 don't boot
I have a Yokogawa WT3000 Power Analyzer which I was using with no problems and then I turned it off to take a break. An hour later, I tried to turn it on and I notice that it shows nothing on the ...
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What does an accuracy of 0.1% + 20 mV mean in a power analyzer's data sheet?
I need to know the measurement accuracy of Keysight N6705C power analyzer. I came across this document (N6700 Modular Power System Family.pdf) that states the error in terms of a percentage plus a ...
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Best tool for measuring short duration voltage/current?
I'm reusing a watering timer (Melnor 4-port) by removing the circuitry and using only the latching solenoid-driven valves with my own microcontroller. I'd like to determine exactly how much voltage/...
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Watt meter connection in three phase circuit
Does the zero point "where all the voltage coils are linked " in this watt meter connection indicates that the power measured by each one of the watt meter is the phase to neutral or the ...
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Measure transformer real power
I’m new at making transformers myself, and the ones that I designed had the correct output voltage, and when they were connected to batteries (previously rectified), they give me a an approximate of ...
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How to sense a varying current and voltage without affecting the load
I've been asked to build a circuit to switch a constant power (varying current & voltage) supply between two loads, for a research experiment the customer is carrying out. The loads are unknown ...
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Measuring 115 V on microcontroller analog input
I've been tasked with switching a number of 115 VAC, 60 Hz supplies to various pieces of equipment, and monitoring these output supplies on a PIC18. I'm confortable with the PIC and ADC side, but ...
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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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PAC1921 power monitor issue
I'm trying to measure voltage, current and power by PAC1921 IC.
This is a PAC1921 datasheet:
PAC1921 DataSheet
This is my schematic:
3.3V_Input is input from simple AMS1117 3.3 V regulator and +3.3 V ...
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voltage dividers on inputs to current/power monitor ic
I want to measure the current and voltage of exponential decay pulses delivered to resistive loads. The pulse peak voltages are between 20V and 400V and the time constants are between 1ms and 20ms. I ...
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Measure power & energy usage in tapped line
Here is the schematic of the circuit in question:
The horizontal lines are from the AC mains. Ammeters and wattmeters are connected at any 2 points in the main lines. I am trying to detect if the ...
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363
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Can a single CT Clamp go to 2 energy meters?
I have a Split Core CT CTSA016 - 100A/50mA Yuanxing CT Clamp (Datasheet) around my mains - and it is feeding into my Solar Inverter.
I have just purchased a Shelly EM 2 Channel WiFi energy meter to be ...
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Highly accurate DIY friendly (cheap) power load
To avoid XY question, I start with my motivation and then my question.
I have an Emporia Vue2 (in-panel) power sensor but it is known not to be very accurate. For me there is a discrepancy between the ...
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Power meter integrated in a circuit
I am constructing an electronic circuit that requires a power meter with a voltage signal output that represents the changes in power in a resistive load. It is crucial that the phase of this signal ...
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Measure unbalanced tri-phased power with 2-channel scope
Our robot is supplied trough our own "supply block", which is converting 3 phase AC (without neutral) into DC current and powering a 2 smaller devices directly between 2 pairs of phases.
...
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Comparing power requirements using AC and DC to power radio equipment
I'm trying to understand the different power requirements for a particular piece of radio equipment that I have. It has the capability of being powered via a bespoke AC or DC power supply.
The AC ...
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Is there an objective standard for power measurement?
Is there an objective standard for power measurement?
I've been confused. My background is not in EE, but I've been interested in the ways to measure power. I've learned that there are many different ...
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Active power measurement via current probe, how does it work?
How does the Emporia Vue 2 work?
It uses a current measurement: magnetic core with coil around it (that’s my understanding). However, without knowing voltage waveform, active power can't be calculated ...
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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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How does a current transformer system know the direction of the power?
I know that it is important to connect a current transformer the correct way so it does not appear that the power goes from source to load.
But how does this work exactly? Since it is AC system it ...
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Is it possible to get an estimate of the power consumption of a circuit by modeling it with controlled sources?
Let's say I have an op-amp. We can measure the power consumption of the circuit by multiplying the current supplied by the voltage supply with the voltage of the voltage supply.
Now, suppose this op-...
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Smoothing quickly changing current/power draw for easier measurement
I want to measure the power consumption of an IoT device with LoRa module.
I read quite a few posts about this topic and two issues come up regularly:
the high dynamic range needed and
the high ...
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79
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How could you determine the point in time a Radar antenna is directly facing a stationary RF receiver station?
I am currently doing experiments involving Software Defined Radio and Radar systems. Since I am new in this field and currently try to refresh my physics/math skills, I encountered some problems along ...
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69
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Can I use a 1-phase analog electric meter rated for 230V to measure 120V current? would my readings be off by a factor of 2? or would it fail?
I am buying some cheap german 1-phase analog electricity meters and plan to use them in Central America. the german meters are rated for 230V and feature the old turning disc mechanism. In central ...
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Current measurement in high side with a range of 200uA and 200mA
I am planning to use the Maxim Current Sense Amplifier(MAX9634HEUK+T)with a gain of 100V/1V implemented as HIGH-SIDE to measure the system current in both normal working mode and sleep mode.
I am ...
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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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Measure mWh - mAh of an MCU-centered circuit [closed]
I build battery-powered circuits with MCUs that consume a few uA in sleep "stage." For total power consumption measurement (and therefore battery-lifetime), I used to use this but recently ...
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What is a cheap device for measuring low-power IoT devices? [closed]
what are some cheap (around 50 USD) devices for measuring and logging the power consumption for low-power devices (like IoT, for example)?
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Can RF power measurement be done using a temperature probe?
Can RF power (at HF frequencies in the range of 0 to 40 dBm into a 50 Ohm load) be measured by a thermometer or other temperature measurement device on the termination load?
If so, what kind of ...
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Measuring AC power output from harvester
In order to characterise an energy harvester, I want to measure its power output. It is a rotary harvester (basically like a regular generator) with three phases.
I do not have fancy measuring ...
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Can we also use conjugate of Voltage (V*) for measurement of Complex Power?
Why is S = V I* is used a lot? I have never heard a mention of S = V* I. (It does the same job as I*). We get the phase differences in both the cases due to conjugation. So I'm assuming it is right to ...
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Generate 1W load on 240V mains to calibrate power meter
I need to measure the accuracy of a mains power meter at around 1W.
How can I go about it?
Despite being clueless about electronics, I do have some a Tektronix PA1000 Single-Phase Power Analyser that ...
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91
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Calculate Current Inside the Resistor
So i have a green LED with the Vdrop: 1.9V ~ 4V, Vforward: 2.2V, two AA battery in total 3V and a resistor which has 300Ω.
I place all the component like this and star to measure and calculate all ...
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Safely measuring voltage from solar panels in an experimental research field
(Note: I asked this on https://engineering.stackexchange.com/ but I was told I should ask this here, so this is what I'm doing.)
I'm installing solar panels (not connected to the grid) in units out in ...
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Split wires for the purpose of measuring high currents
According to I need an amp meter that requires no splitting of the wires there is an accessory that splits wires for the purposes of measuring current.
From the looks of the device it's limited to ...
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Reading current with YDHC SCT013 split core transformer and RPi or Arduino
I've got a few split core current probes YDHC SCT013 that I used to use with an Open Energy Monitor module that has failed some time ago.
Now I'm looking at building a replacement power monitor ...
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Why has my tweeter speaker burned up?
I bought a powerful tweeter (or so I thought) to experiment with the ultrasound. The device is quite heavy, and it is rated at "350 watts RMS/700 watts peak": 2'' Titanium Super Tweeter ...
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What does SWR and reflected power mean in terms of power actually dissipated in a load?
I'm struggling to understand the "meaning" of VSWR in the context of power delivered to a load.
Say I have a transmitter operating at 10MHz, a short (~1m) piece of assumed-lossless ...
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Power measurement on multiple loads
I'm designing a circuit for driving multiple loads (min. 16, up to 64) like the one shown below
simulate this circuit – Schematic created using CircuitLab
The input source is from a multi-...
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What type of circuit or component is used to sample RF power?
I'm building a 2-stage RF power amplifier and I would like to measure the RF power at each stage and report it to a microcontroller on the board:
...
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Measure power of solar cell with an ESP8266
Scenario
I plan to buy some bigger solar cells (together around 500 W) and use them to make my electricity bill cheaper. In order to find the perfect location on my roof before the purchase, I thought ...
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Pulsed DC power calculation
I'm trying to measure the power consumption of my device using a shunt resistor. I'm measuring both the voltage over my shunt resistor and the source voltage. With a math function i'm trying to ...
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Three phase AC power measurement
I am trying to measure the output power for BLDC controller, in order to calculate the efficiency of the controller. I came to know that two watt-meter method is one of the method used to calculate ...
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Power monitoring difficulties using ACS71020 30A SPI and PSoC 5LP
I'm currently developing a board for my dissertation that should monitor voltage, current and power consumption of a given load. For that purpose I chose to use the Allegro ACS71020. The one I chose ...
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Current / power measurement using ACS71020
I am having some hard time in understanding and comprehending the value for ACS71020 current and power measurement. In the manual, rms_avg_1 and rms_avg_2 has been mentioned stating that "The
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Is there any device or way to measure how many watts a computer's processor is using? [closed]
I know there's a device to measure how many watts a computer is using, you get an energy meter you plug the computer into it and it tells you
But I'm interested in finding out how many watts a ...
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Measuring nanoamp range current consumption
I am looking to buy one of Joulescope, ZS-2102-A (angler circuits) or Otii (QOITech) to measure power consumption and get graphs of current consumption for some low power BLE/WiFi devices. Does any ...
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Transformers and wattmeters
This is, probably, a very silly question, but I was thinking:
If you have a watt meter and you connect a step up transformer with the lower voltage side attached attached to it (both the voltage and ...
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