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TR2/3/3A Ballast resistor to prevent hyperflashing

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Jim_Stevens

Jim_Stevens

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I’ve shifted over to led positive ground turn signal lights using the original style Lucas flasher. I installed two 5-ohm 50W resistors to ground, one on each side, tapping in at the bullet connectors each side. I’m still getting hyperflashing and no clicking sound at the flasher. The resistors do get warm to the touch, so they are carrying current.
I pulled the flasher out and checked it with an incandescent 40W bulb, tested sat.
I’d have thought 5-ohms would have worked, but evidently not. A 3 or 4-ohm resistor may be needed to induce enough current to trigger the flasher. Anyone have any experience? Jim

TS 44743L “O”
 
I had a hard time finding flashers that would work correctly with the stock lamps (and my original failed), so I haven't tried a resistor with the stock flasher.

But, spec is 21 watts per bulb, which if I've done my math right, works out to 3.5 ohms. Assuming a 50% duty cycle, that's an average of 20 watts at the resistor, so a 5 watt is going to get VERY hot.
 
TR3driver said:
I had a hard time finding flashers that would work correctly with the stock lamps (and my original failed), so I haven't tried a resistor with the stock flasher.

But, spec is 21 watts per bulb, which if I've done my math right, works out to 3.5 ohms. Assuming a 50% duty cycle, that's an average of 20 watts at the resistor, so a 5 watt is going to get VERY hot.
Click to expand...

Totally agree— using 50W! And will order 3.3ohm, 50W resistors straightaway. Jim
 
Jim_Stevens said:
Totally agree— using 50W! And will order 3.3ohm, 50W resistors straightaway. Jim
Click to expand...
And just for future queries, I ran it with both 5-ohm resistors in parallel (2.5 ohm total) and he blinkers worked fine, so I’m assuming the 3.3ohm ones I just ordered will work out too.
Somewhat surprised that the 5ohm ones didn’t work, but live and learn once again in this humbling hobby!
image.jpg
 
I'm using a pair of 6 ohm 50 watt resistors with LEDs only in the rear lamps. Seems to work fine though sometimes the dash indicator flashes rather weakly.
 
Geo Hahn said:
I'm using a pair of 6 ohm 50 watt resistors with LEDs only in the rear lamps. Seems to work fine though sometimes the dash indicator flashes rather weakly.
Click to expand...

No idea why your 6ohm resistors work whilst my 5ohms didn’t. That said, the new 3.3ohm ones came and I installed, and the flashers work fine again. on the dash, I’m using an LED bulb there too. Plenty bright!
 
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