Re: 360 degree LEDs

On Jul 20, 11:49 am, frenchy <mf101...@xxxxxxx> wrote:
thanks!

Vf is actually 3.2v (not 1.5) for the 360 degree LEDs so the
calculation for the resistor should be adjusted accordingly. Also the
maximum continuous forward current is 20ma for the RL5-W45-360 and
60ma for the RL8-W110-360 so you can use different resitors for each
of these.

The GI strings are 5.7 VAC (which means an 8v peak) and Vreverse max
for this LED is only 5v so you will need to account for this. The
parallel and reversed LEDs suggested by Beaver will work or you can
put in a series diode (this is the technique used by Stern for the
LEDs that indicate the power to each GI string). If you use a series
diode you should subtract 0.7v off of the voltage for the resistor
calc.

Actually with AC the resistor calc is not quite accurate since the LED
only conducts less than half the time (also, note that this makes the
LED less bright than you thought it would be) but the peak current is
actually higher (than the calc using 5.7v ) since the peak voltage is
8v. The value of resistance calculated assuming DC is conservative
(especially for the RL5-W45-360). But it is a start.

If you were using a bunch of these LEDs to replace GI lights you'd be
better off rectifying the GI power at one place. No series diode and
a brighter LED (w/less flicker).

Rick



.

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