Pulsed LEDs at end of cable = EMI problem?

[eem2am]

Hello we are PWM dimming our 6_series_LEDs string.

The current in the LEDs is 330mA. (obviously the average current will be less when the PWM dimming commences).

Here’s a picture like our set-up.

https://i49.tinypic.com/2wmoxg6.jpg


These LEDs are at the end of 3 metres of cable.

So the 330mA “square” pulses are being sent down that cable.

Will this cause a bad EMI problem.?
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[karesz]

Hi,

I dont get your picture, but with a "3 m length of cable" you have a nice antenna_ good chance for a first class EMI problem to become...
You have some 10 or 100nsec edge times of the LED-Current pulses, assumed 100nsec: basic frequency will be at 30MHz, with harmonics upto the TV bands...
I think you must apply minimum a shilding over their and check for sendet signals/EMI effects.
You can check it for first width some transportable FM/HF & UHF receiver_maybe TV too...
K.