Questions tagged [dummy-load]
A "dummy load" is a replacement element for an item that would normally function as an electrical load.
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Power dissipation calculation of MOSFET: for selecting a MOSFET as Dummy load
I am designing a dummy load, and it should be capable of sinking around 75 A @ 80 V (not always, varies from 10 to 75 A). I want to choose MOSFET for the application as shown in the image.
I would ...
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Can I control IGBT linearly with gate voltage?
I want to make a dummy load using IGBT. Is it possible to control the Ice (collector to emitter current) using the gate voltage? It would be really great if it is possible to explain the answer. The ...
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How to find minimum load for 5V rail of the power supply?
I have 450 ATX 12V V 2.2 power supply. I am going to use this power supply as my power bench supply. But I couldn't find the minimum load that takes on 5V rail. Beacuse its pretty old PSU and no ...
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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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Conveyor zero speed problem relay, smart relay
Our company bought a bunch of outdoor conveyor belts that need to plug into each other for power and communications. The power is 4160 V and each one has a transformer to 480 V. That power is ...
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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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Is there anything particularly special about a "short" and an "open" in a VNA calibration kit?
I would like to calibrate a VNA with the reference plane at the end of a male BNC feedline. Surprisingly, female SOL kits are hard to find. There are many BNC 50-ohm loads available but I'm having ...
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Simulated speaker dummy load for solid state
This is specific for 6 string electric guitar amplifiers. The convention appears to be use a resistor equal to the nominal DCR of the intended speaker load, usually 4 or 8 Ω.
What I have found out was,...
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Will a 10 Ω resistor create 2.5 W of dummy load on 5 V line (using an old ATX PSU)?
I am trying to understand something about dummy load resistors.
I have an old ATX PSU. It has a 5 V line; maximum is 34 A, but it says it needs a minimum of 0.5 A. That means it needs a minimum load ...
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Is there such thing as a load generator for testing a modular power supply unit?
I have built a modular power supply - and I was wondering if such thing exists to generate a mock load.
I have two supply blocks and I need to make sure they are supplying adequate current. I can hook ...
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Is this avalanche rugged MOSFET suitable for linear operation?
I would like to create an active load which draws current(4 to 6A) from a 12V battery. Unfortunately, the shipping costs and delivery times have prevented me from buying Linear FETs directly from well ...
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Help with Dummy Load Design
I'm trying to make a dummy load inspired by this one by GreatScott, and I'm using parts I have on hand. Here's the constant-current source design I'm using:
I'm hoping to test a 12V power supply with ...
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Dummy Load to test a 200 watt 24 volt supply
I feel like I have a simple question that hopefully can be answered quite quickly. I have a 24V power supply that is supposed to achieve a max output of 200W. Recently, I have reason to believe that ...
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50 ohm Dummy Load With 50dB Attenuator
I am designing a 50 ohm 10 watts dummy load for 100-1000MHz frequency range. The signal strength should not exceed -10dBm.
The load must be able to dissipate 5 watts minimum, that is +37dBm.
The ...
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Test "wall wart" power supply
I am purchasing a 3 ampere USB A power supply (5V.) What would be the easiest way to apply a known load from 0-3 amperes (in 0.5 ampere increments, for example) so that I could connect a multimeter ...
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What should I use as a test load to calibrate a UPS?
I have a 1440VA (980W) Uninterruptable Power Supply (UPS) which I bought a while back to protect my computers from power fluctuations and possible outages. Recently the battery failed and so I ...
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HowTo create an accurate constant-current dummy load using immersion heaters controlled by Arduino?
Given: variable sized nominal 3.2V LI/LFP battery cells, from little 18650 / 26650 cylindrical A123s up to large prismatics from CALB / Winston etc.
the desire to capacity-test them off grid (no ...
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Where did I miscalculate ohms law in my experiment?
I thought I finally had a grasp on how ohm's law works but when I set up an actual experiment, the numbers don't match up.
To keep a long story short, I converted a computer power supply into a lab ...
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Electronic load, Problem turning MOSFET on
I am trying to make an adjustable dummy load to test a 12V supply, I’m having trouble with the op-amp feedback circuit.
Attached is a simplified schematic. I have tried lots of things and stripped it ...
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Which wire should I use as dummy load for this specific PSU
I'd like to make lab power supply out of my old ATX Power supply. I am beginner in electrical engineering and this project seems pretty straightforward. I've checked many tutorials about it and ...
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Electronic load for negative voltage PSU
I am making a MOSFET based electronic load to test my PSU rails.
Below is a simplified version of my circuit with V2 as the PSU that is being tested. I want to be able to test negative voltage rails ...
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reactive power for power meter test (load bank)
I want to test a power meter and I need to test both active and reactive power. I use a resistive load bank to test active power. Now I want to see power meter performance in reactive loads. For ...
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How do I determine the range of wire wound adjustable resistor?
I'm looking at buying a 300W tubular adjustable resistor. Like this:
https://www.digikey.com/product-detail/en/vishay-dale/RBEA03001R000KFB00/541-10193-ND/9765057
Digikey has four part numbers in ...
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Stress testing a PCB’s current handling capability?
I’ve produced a simple unregulated power supply PCB, consisting of:
AC input terminals
Fuse
4 rectifier diodes
Filter/smoothing capacitors
DC output terminals
Only when the PCBs arrived did I get ...
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Thermal Management for Arcol HS50/HS100 50/100W Wirewound resistors
I'm designing a 100W dummy load for a guitar amplifier using Arcol HS50 and HS100 resistors. Here's a link to the datasheet:
http://www.arcolresistors.com/wp-content/uploads/2014/03/HS-Datasheet.pdf
...
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4-wire voltage sensing for DC load
I'm building an electronic DC load. I'd like to implement voltage sensing (4-wire sensing). I made this schematic:
Input voltage can be up to 60V, this circuit basically divides it by 6, and output ...
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AC analysis of opamp loop in LTspice
I'm building an electronic DC dummy load and have a problem with stability/oscillations.
This is my circuit:
Vset - controls current, when set to 100mV it makes 500mA at the shunt
Vout1 - Vshunt ...
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Problem with opamp stability in DC load
I'm trying to make DC load up to 20A with 1mA precision.
Current sense resistor is 5mΩ, so the voltage on this current sense will be from 5μV to 100mV.
I picked LTC2050HV (datasheet) which have very ...
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Can I use two 10 ohm 5 watt resistors instead of one 5 ohm 10 watt resistor?
I am working on converting an old ATX PSU to a lab bench power supply, and the guide I follow is putting a 5 ohm 10 watt dummy load resistor on the 5 V supply line. I don't have resistors of this ...
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Need help to find correct values for dummy load resistor
I am working on converting an old ATX PSU to a DIY lab bench power supply. Everything is going well, but I can't seem to find out the correct dummy resistor load values.
The 3.3v rail has 22A and the ...
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Cheapest dummy load? 450w, 15V, 30A, only for a few seconds
What is the cheapest and simplest way to dummy load 450w, 15V, 30A, only for a few seconds?
I would like to measure the max output capability of an MPPT charger controller, basically as a "all losses ...
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Using a DC Electronic Load vs power resistors (dummy load)
When setting up a test to evaluate a DC power supply, would using a power resistor suffice? I have a 5 V power supply hooked up directly to a 5Ω 20 W resistor to pull a constant current of 1 A. When ...
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What's the purpose of the resistor in a 3A load box
There is a resistor R5 in the 3A load box below. It seems it add some positive feedback to Q1, but I'm not sure. What's the exact reason to add it? The circuit comes from here.
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Constant Current Load ampere measurement
I have the following circuit that I am building, a constant current load):
I am using a 9 volt battery and a 1.5 volt battery to power the circuit. My load under test is a AA battery. Based on this ...
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Can aluminum-housed resistors be used as dummy load for battery testing (etc.)?
I want to buy me one higher-quality resistor to have a durable and stable dummy load element suitable for use in battery testing and other purposes.
I've come across a 100 ohms / 10 W one which is ...
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Solar charging using or not using a dummy (dump) load
I'm in the process of designing a small solar regulator / charger (no more than 5A) for sealed lead acid batteries. I have put a working prototype together and all seems to be working.
However, ...
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Some problems with my dump load controller
The requirement is an automatic dump load controller; for balancing lead acid or lifo batteries. While the input voltage is above 1.75V the circuit should dump 10A into the load continuously.
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Adding voltage divider to output of power amp concerns
I have a load box I use to test and burn in analog audio power amplifiers. Each load box is tailored for a specific amplifier circuit and for one of the load boxes I would like to add an LED that ...
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Simple, Variable High Current Dummy Load
I'm working on a power supply build and need a dummy load. I've found many mentions here that are good for a few amps, but I need one that's good for 30A or more... at 5V. I thought about just using ...
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Input Protection for an Electronic Load
I'm currently working on a dummy load designed for testing small power supplies less than about 10V. I'd like to provide reverse input protection to prevent the op-amps from being damaged. Because the ...
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Creating a specific volt/current "test load"
Working on a complex power supply, but to test its limits I would like to create a set of test loads of specific voltage/current.
There are several devices for creating a set load, but they seem to ...
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ATX PSU: Simple dummy load?
To use an ATX supply outside of a PC while preventing output voltage to run away at low/no load, can I just use a couple of diodes in series to provide some kind of voltage-dependent load?
Like:
...
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Load generator for testing power supplies
I have some DC-DC power supplies that I would like to test. (about 10 or so).
PSU specs:
Input 6-30V DC
Output 8V DC, 2.5 Amps max.
As I don't have the budget for a DC Load generator, I'm looking ...
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How to dissipate a lot of current
Lets say I want to test out a sine wave 120V 15Amp inverter by drawing 15 amps of resistive load. How can I draw this without generating very much heat, and optimized for as small as possible.