Questions tagged [testing]
Proving the proper operation or finding faults in an electrical device. It can be done using electronic test equipment or by a software-based simulation.
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What is expected error rate and drop rate on ST-Link VCP USART?
What is expected error rate and drop rate on ST-Link VCP USART?
On the Nucleo STM32F446RE, my code reads the USART VCP (of ST-Link) and echoes it back. It uses DMA, FreeRTOS, and FreeRTOS queues (...
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Creating a test jig for a large PCB Backplate
I am a recent graduate working on a side project that involves creating a test jig/method for a large PCB backplate. Unfortunately, the original layout and diagrams are no longer available, so I need ...
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How to determine delay of sensor response after the stimulus event (with oscilloscope?)
I’d like to determine how long it takes a digital sensor to go low after the stimulus event (Ir break beam). I have no problem getting a trace from sensor: I can see it start to drop, the slope, ...
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Mean Well Power supplies have much lower efficiency and much higher leakage current than rated
I am going to have a power supply which will always be connected to AC mains and occasionally, a led strip will be connected and disconnected to the supply with a relay. I want an efficient and low &...
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How can I check continuity longer than my probes?
I'm trying to sleuth out a wrongly wired connection on a small injection molding machine. I'm starting by verifying the connections match the diagrams from the manufacturer. However, some of the ...
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Measurement of relay characteristics so can detect before failure
I am working with a very large safety system which was designed around 30 years ago. It has a system of relays interlocked together in a logic configuration so that it will failsafe if any relay ...
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What ground pad should be put on a PCB for testing?
When designing a PCB, it's common to place pads as test points. What about ground for test? Should I just place a pad connected to ground? The problem is that it's hard to manually hold probes to two ...
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2A223J fixed capacitor immediately shows OL on resistance test
I have a 2A223J fixed capacitor. When set in resistance mode, I'm showing OL when tester leads are touching each (separate) capacitor lead.
I just tested a new .22uF capacitor and i saw resistance ...
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How to write tests for a clock signal
I am using GHDL to create an entity called HEARTBEAT, which is a simple clock signal. I already wrote some testbench for other entities like AND or NOT gates. Now I am wondering how can I write tests ...
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Percentage difference of winding measurements
I am trying to learn more about the proper winding measurement of power transformers.
In this regard I am following this tutorial https://www.youtube.com/watch?v=3HIEIoa4NKA&list=LL&index=2.
...
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Megger terminals clarification
I saw that some meggers inject the test voltage / current from the - (minus) terminal while do this from the + (plus) terminals (don't know why, it probably depends on the manufacturer?)
Currently I ...
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Self testing PCB [closed]
Is there a way that I can test my PCB by myself (if it works properly or not) before sending the design to the manufacturer? Like if Altium has some kind of feature like that? Or is there other ...
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Can I use a contact microphone to detect a fan running / not running inside an electronic product?
I'm involved in thermal testing of an electronic product which contains a small centrifugal fan. The product is entirely sealed and no signals can be transmitted through the case when it's operating.
...
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How to isolate multiple 24 VAC to 5 VDC power supplies (buck converters) that are all powered by a single main transformer with a common pole?
Basically, I am trying to test multiple relay controlled outputs that are all 24 V outputs. One pole of the transformer is going into a relay for each device and the other side of each device is ...
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How do you choose the right load for reliability testing?
I am an automotive reliability and test engineer. I do environmental or electrical tests and during these tests I need to load my products. By load I mean, for example, there is a mosfet driven by a ...
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Does the quality of USB cable affect the power drawn?
I was wondering how the power drawn is affected by different cable? I tested two different types: A USB cable plugged to a USB digital tester which showed a power of 4.88 V and 2A drawn, whereas the ...
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What extra battery information do you get by using a two tier dc load method VS the one tier method?
I learned that these of these two methods the one-tier method can only measure the internal resistance of a battery but you get more information from the two-tier testing method. However, the resource ...
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Can products be imported to US for Beta testing without FCC certification
We need to import two products that are newly designed and operate on wifi and BLE. We are planning to get them for beta testing. We have talked to a few interested parties where the products will be ...
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Is there something like a banana plug that will fit in a 30mil or 50mil through hole test point?
I am developing a cost sensitive product. The printed circuit boards need to be programmed and tested. It seems like a waste of money to put a programming/test connector on the board just to use it ...
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Synchronizing signal generators with shared LO
I'm currently trying to test my ADC chip using two signal generators. Below figure visually illustrates how the test setup would look like:
The traditional approach uses a 10 MHz reference port to ...
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How to test photo interrupters
I have come upon two photo interrupters in a calibration kit circuit. The circuit seems to not respond. How can I check these photo interrupters? The green LED is responding when an object is brought ...
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Screw Terminal Test Clip
I have a board fitted with a 10-way 3.5mm screw terminal in a similar style to what you see here (GSO14V-3.5):
I am after a reliable contact to four of these points for testing purposes, without ...
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How to test Raspberry Pi Pico after soldering header pins?
I just got my first Raspberry Pi Pico and I don't have any experience in electrical enginering.
The book I'm following indicates that I first have to solder the and the first step is to solder the ...
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How can I make a load inductor for a double pulse test?
How can I make a load inductor in the lab with value of roughly 115 uH for the sake of a double pulse test measurement? Do I need an LC meter to do that?
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What safety measures should I take during a high voltage test?
I am planning to do a test with 800 V DC system in the lab. I have taken the high voltage safety training but it's my first time working with high voltage so I want to make sure that I am taking all ...
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Predicting health of power supplies
I have a couple of 12 V, 1200 mA wall mount power supplies.
Currently, using a digital multi-meter, I am able to measure good voltage and amps coming out of some power supplies.
Since these are ...
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In-circuit MOSFET testing
Can I test a MOSFET in-circuit using the multimeter? I have an N-channel MOSFET with a minimum of 3 V Vgs(th).
Update: Adding schematics for clarity:
Thanks,
Nithin
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How to design a transformer that can inject 350A for 1-2 sec - for testing short circuit tripping of 32A type C MCBs
I am trying to design a transformer that can be used for field testing of MCBs up to 32 A (Type C). The testing (for short circuit tripping of The MCB) will require maximum about 350 A to be injected ...
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LCD screen panel stuck in BIST mode
I have a BOE DV430FHM-NN0 LCD screen panel with an LVDS 30-pin receptacle cable. It was happily working with a M.NT68676 board, but one day when I connected it to the same board, the panel suddenly ...
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How can I test a bench DC power supply?
I am about to receive a new dual 30V/5A DC bench power supply.
The goal is to use it in lieu of batteries to build simple circuits.
I'd like to test it out when I get it, but don't really know how to ...
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Checking the LC245A on board
I want to know how to make sure that the LC245A on the board in the image is not damaged.
The problem is that some buttons do not work. The short circuit remained when I removed the two pieces in the ...
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Which electrical components can be measured while still soldered to a PCB already, and under which circumstances? [closed]
I can't seem to find a coherent and thorough answer to this question anywhere on the internet. I know about this Stack Exchange post asking a similar question in the title but none of the answers ...
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Testing digital transistor
Is there any difference in testing procedure for digital transistors since there are resistors?
I'm trying to check a C114E transistor but I can't find a datasheet to affirm the pinout. Assuming that ...
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How do I establish if an op-amp is bad?
I have a JRC2374 SOIC8 IC on my board which is not powering up. The IC seems to be involved in the power regulation switching operation. Here are the internals from the datasheet:
I know little ...
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Information leakage due to fault propagation in XOR gates
From the paper Fault Template Attacks on Block Ciphers Exploiting Fault Propagation, in the concept of Automatic Test Pattern Generation (ATPG), two events are required to perform in sequence: Fault ...
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Very, very sensitive (but possibly very inaccurate) method of detecting voltage differences
I have a test setup where I need to be able to tell if there is a voltage differential between 2 nodes, but not affect the circuit at all. Some would suggest to using the voltmeter function in a ...
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Reed Switch Selection - Quality Control
I have a piece of hardware which uses reed switches and neodymium magnets. When I attempt to produce this hardware in batches I find that some reed switches that I have are more sensitive than others ...
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UPS doesn't provide any power on battery - Battery broken? [closed]
I have a CyberPower CyberPower BR850ELCD-AU UPS.
It is a couple of years old and when I tested it a few days ago, I noticed that on battery, i.e. unplugged from power it does not provide any power to ...
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Can a BNC through-load be used as the load to SOL-calibrate a VNA?
Related to this question, I'm having a hard time finding a female 50-ohm load to calibrate a reference plane at the end of a male BNC feedline. However, feed-through loads are readily available.
Is ...
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Dense Neuron Neural Network in Verilog
I am trying to build NN in system verilog, but I am facing a problem with neuron implementaion, as it only displays 'x'.
...
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Circuit for Li-ion cell cycling testing
I'm researching lithium-ion cells and want to construct a physical setup to test how a Li-ion cell's behavior changes over many discharge-charge cycles, i.e. gather data similar to
I plan to use ...
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Having trouble verifying op-amp on circuit board
I'm having trouble verifying that I understand how op-amps work (because I clearly don't!). I've hooked up the following circuit on my breadboard:
The voltage sources are two 9 V batteries, the ...
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Problem with an LM35DZ temperature sensor
I bought three "LM35DZ" temperature sensors, all of them are from National Semiconductor.
When I connect +5 V (4.90 V actually) to the Vcc pin, and its GND pin to 0 V, I get 0 V of output ...
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What is the difference between Test-on-Target and Hardware Software Integration (HSI) testing?
We have an Excel file which has many test cases written for high-level software requirements. We want to categorise these test cases based on the test category i.e. whether it can be Test-on-Target ...
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Why does the variac make a "zing" sound during testing?
I've tested my prototype transition mode 80 W boost PFC with 220 VAC input and 400 VDC output. When I supply the Vcc of the controller and start the switching MOSFET, after a couple of minutes, the ...
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What is a correct method to measure safe maximum voltage of a PCB?
I have a small (24 x 15 mm) PCB for a custom connector. It is intended for low voltage (< 48 VDC) applications, but I am interested in measuring it in order to provide customers a reasonable ...
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Lead-acid battery screening options
We have a situation where we have on-hand many tens of thousands of 12 V lead-acid AGM batteries. The vendor had production issues, and we've found around 5-10% of these have an unacceptably low ...
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Possible to detect phase number in a three-phase system?
I have a 400V three-phase [TT system][1] that I use for my company in Italy.
I was wondering if there is a direct way to detect the phase number at any point in the wiring.
I have the phases numbered ...
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TVS Diode Testing
Nowadays, I'm tried to use a TVS diode but I think it is damaged. How can I test a TVS diode? How can I understand that is it working or not? What is the best way to test TVS diodes?
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How can I test if an IC output is buffered?
I have some CD4069UBE and some CD4069BE. From what I understood, the UBE ones should be unbuffered and the BE ones buffered.
But I don't find any datasheet that shows some buffered 4069, so I'd like ...
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