Re: 9W LED inrush current

On 03/10/2024 01:32, Don Y wrote:

On 10/2/2024 1:32 PM, Don Y wrote:

On 10/2/2024 12:13 PM, Martin Brown wrote:

On 02/10/2024 13:03, Pimpom wrote:

On 02-10-2024 03:21 pm, Jan Panteltje wrote:

On a sunny day (Wed, 2 Oct 2024 12:01:47 +0530) it happened Pimpom
<Pimpom@invalid.invalid> wrote in <mN5LO.101241$CStb.23546@fx12.ams1>:
>

Does anyone have a figure for the switch-on inrush current of a typical
9W LED bulb? Preferably for 230/240V.

>
Not sure wat the 'typical' circuit is, this is wha tI found in my LED bulbs from Cina:
  https://panteltje.nl/pub/LED_light_circuit_diagram_IMG_6925.JPG
   peak current is limited by the 1uF series cap at 50 Hz here.
There are so many different LEDs around,...
>

Ah, I should have formed my question more carefully. I know about those early bulbs. They were the precursors to modern ones that use switching supplies. These later models are the ones I mean.

>
It is still likely to be fairly small since the cheap parts they use are not capable of more. Only way to be sure for a specific brand is to measure it. I'd expect no more than 2-3x its nominal operating current. The reservoir capacitor is seldom bigger than needed to avoid visible flicker and sometimes not even that on the cheap and nasties.

>
For lighting *installations* (i.e., not individual lamps), I think they
use 100x the steady state current as an upper figure.  This is intended
to cover model and manufacturer variations.
>
With multiple lamps on a branch circuit (or whatever is driving them),
this can add up pretty quickly.
>

Why do you need to know?

 <https://adlt.com.au/resources/led-inrush-currents/>

Thanks for the link - that seems definitive and on high end units too.
I had perhaps naively assumed that they would put a small inductor in series with the thing to limit worst case inrush current. It is only for a very very short time though ~100A for <1ms which real fuses won't even see and most domestic circuit breakers probably won't either.
By comparison the arc caused by a filament spotlamp in the kitchen going pop bang almost always exceeded the max trip current by some margin.
My lighting circuits are now almost exclusively LED based and I have never seen any signs of trips. Although I never put all the lights on at once and then done a system mains power off/on at the breaker box.
That is about the only time that this 100A surge risk becomes a problem. One of my switched loads is 10x 7W LED candle lamps and has never caused a problem. Back when it was 10x 40w incandescents it was a heat source!
--
Martin Brown