How to build 48 volt turn signal flasher

[NeilP]

Any one have a circuit that will flash turn signals on a 48volt e-scooter.

It was 36 volt, but had battery upgrade to 48-50 volts, and the old flasher unit let its smoke out.

Front bulbs are 40volt 3 W and rear bulbs are 12volt 5w with a big 2 inch 47ohm wire wound dropper resistor. Cant find suitable rear bulb style in correct voltage, hence the 12volt rears.

Original flasher is two wire unit consisting of :
3 resistors
2 electrolitic caps
Diode
Buzzer
Small 3 pin un marked signal transistor
Larger (taller) 3 pin 'transistor' ...? Darlington pair package possibly if my reading of markings is anything to go by. D1978 or similar

Not reversed the board to schematic yet.

Just wondered if anyone had a suitable ciccuit ready to go to save me the hassle.

 

[amberwolf]

There's a few variants of flashers here:
http://www.4qdtec.com/putpr.html
which at worst you'd need ot recalculate resistor values for.

 

[NeilP]

thanks, will take a look

 

[r3volved]

My buddy uses a 48V to 12V converter. he doesnt have flashers, but he runs his other lights and his remote start unit all off that.

Edit: (example) http://middriveebike.com/p_dcconverter.php

 

[NeilP]

probably would be perfect for the job, cowpled with an off the shelf 12v 2 wire flasher unit..a lot less work for me...it is for a shitty chinese 'Thompson euro city' plastic scooter look alike bicycle.

if it were mine i'd douse it in petrol and burn the bloody thing, ( after removing the only 2 usable parts..rear hub motor and standard hall throttle)

 

[teklektik]

Both Lyen and cell_man sell this little unit. Very small and completely potted save for the voltage adjust (paint with liquid Lectric Tape after adjusting). 3A rating.

To keep roughly the same bulb wattage, maybe upgrading the front to a roughly equivalent 12v version, sounds like you need 2x5W = 10W to flash front/rear on a side, so 10W/13.5v ~= 1A. This little guy should give you plently of headroom. You might even bump the bulbs up a bit for better brightness. You could also crank up the voltage a bit from the nominal 13.5v for '12v' systems to 15v to get a slightly brighter turn signal with the same bulbs. 15v is still 'in spec' for any stock automotive flasher you choose.

 

[NeilP]

And just todsy I spotted a pair of orange coloured indicstor bulbs on the old farm runabout. Not registered for road. So can whip blbs out of that