Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [inrush-current]

The high current, that often occurs when first plugging an appliance in the power supply.

Inrush current, input surge current or switch-on surge refers to the maximum, instantaneous input current drawn by an electrical device when first turned on. This commonly occurs in cold incandescent light bulbs, alternating current electrical motors, transformers. The results could be blown fuses, tripped circuit breakers, overcurrent situations.

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Energy efficient inrush current limiting

Short version: looking for simple and energy efficient way to limit capacitive inrush current. Primary design goals are to minimize radiated heat and current draw during normal operation. The schematics must allow intermittent operational current up…
Maple
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Limiting the inrush current

I have a transformer with several secondaries, and this is how I'm planing to control the inrush current: simulate this circuit – Schematic created using CircuitLab I'm using a resistor to limit the inrush current and MCU will energize the relays…
ElectronSurf
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Why does my Inrush Current Limitation not work sufficiently?

I have a battery powered application and want to somehow "protect" the battery from seeing too high currents. For that I have introduced a serial resistor to limit inrush current. After a certain time the resistor gets bypassed via a Mosfet. It has…
gloerk
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How to prevent large inrush current without a reset-fuse

In another question (DC-DC booster fails with lead-acid battery source) I described a problem with a DC-DC booster that destroyed itself by dragging a large current when its output was disconnected. This did not happend when the power source was a…
Gearlos
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Inrush current in Apk/us what does it mean

I'm looking at this LED power driver from a design, and I see it has inrush current speced as 190Apk/400us. Does that mean there's a 190A spike over 400us. That seems a little insane, how would ever control something like that to turn it on and…
confused
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Inrush current limiting in high power inverters without using contactors

We have a 10kW inverter which is used to control a PMSM inverter and need some help to design a better inrush current limiter during startup. The general approach would be to let the DC bus charge safely and slowly via a series resistor, and then…
AK47
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Overview of inrush current limiting (AC/DC convertor)

I'm tinkering with what amounts to a "smart switched outlet"... which is really just a glorified way of saying I have a bunch of devices that run off 110VAC and need 12VDC for internal "stuff". Emphasis on "bunch". I'm looking at e.g. IRM-03-12,…
Matthew
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Can a low side N-channel MOSFET in a DC-DC converter limit inrush current?

I want to add an NMOS just before the supply negative side and thereby controlling its slew rate so as to create a soft start. I've seen many examples but mostly with high side PMOS (high Rds on) or NMOS (additional circuitry to drive in high…
Akash
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Initial current surge

I designed a PCB that takes an input of 110Vdc and steps it down to 5Vdc for a microcontroller and a couple of ICs. At the input, I have a reverse protection diode, an inrush limiter circuit, and a filter: Vin is connected to the DC-DC buck circuit…
HV16
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MOSFET Inrush Current limiter

May I know how to calculate the value of C1, R1, and R2 in the below-shown circuit? The input voltage is 12 V.
Chitharanjan
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LM9022 add softstart for inrush current

I have a VFD filament driver (LM92022) and i need to add a soft start for stop inrush current, for increase life time of the filament tube. This solution its ok? My tube working at 2.4v Ac / 80 ma. LM9022 Scheamtic:
arduplay
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Does limiting inrush current prolong inrush time?

Let's say you have a power supply that at 110 V draws 1.3 A max in its steady state, but has an inrush of up to 50 A. If you want to limit that inrush current to 5 A, you could use a 22 ohm resistor. Easy enough. What I'm unclear on is if you limit…
Derek Hershman
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VFD filament inrush current resistor

How can I calculate the resistance for a minimization inrush current effects, to increase the life of the filament of a VFD tube (IV22). Or is there another technical solution to prevent the filament life decreasing due to this phenomenon? Power…
Miau
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Transistor current limit

Suppose the DC motor has a peak current of 500ma and after that it drops to 100ma, the transistor can switch continuously 200ma. If I limit the current of the transistor from the base current to 100ma, for some reason could the transistor consume a…
Marcelo Augusto
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SMPS inrush time

In the datasheet of the smps supply, I have found that the inrush current of the supply is 40A. But the time period of the inrush current is not provided in the datasheet. Is there any way to find the inrush time period using the specifications in…
kailash kumaravel
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