12V LED Flasher

Thread Starter

Feinberg

Joined Dec 14, 2019
15
Hello everyone,
my unlce asked me if I was able to check out a flashing light for construction use ( Klemmfix Horizon 21307) and see whats wrong with because it didn't light up anymore. On further investigation, the batteries seemed to be fine (runs on 12V input) but the bulb (Xenon flashing bulb) didn't seem to have any electrical continuity between the + and - terminal. There also is a 3rd wire that is connected on a coil around the glass housing (pictures attached). I was wondering if anyone has an Idea for a high power LED flash with 60 flashes/min that runs on 12V or if someone has any idea on how I can find a replacement bulb since the manufacturer doesn't provide any information and the bulb also doesn't provide any specs.

regards
Feinberg
 

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MrChips

Joined Oct 2, 2009
21,133
That is not an ordinary incandescent light bulb.
It is a xenon flash tube. You will not be able to test this with an ohmmeter.
 

Thread Starter

Feinberg

Joined Dec 14, 2019
15
It isn't anything like an LED.
It is xenon flash tube and needs a high voltage between the end two connections and then a high voltage pulse on that middle connection to trigger the flash.
This will give you a starter: http://www.bristolwatch.com/ele/index.htm
Im sorry if the title confused you. I already know that it is a xenon flash tube. However, I cant find any specs. This is why I am looking for a LED alternative running and 12V that I can build myself.
 

AlbertHall

Joined Jun 4, 2014
9,875
Is there any way I can measure it using a multimeter to find any specs for a replacement?
No. It will open circuit everywhere and that tells you nothing.
It is more likely that the circuit driving it is faulty (assuming that the glass envelope is intact).
Does it have any writing on it at all?
 

LesJones

Joined Jan 8, 2017
2,639
I think you will find it difficult to emulate a xenon flash tube using an LED. You do not give any idea of the rating of the flash which will be rated in joules. You would not expect to measure any conductivity between any of the connections on the tube. The tube only conducts when triggered with a high voltage pulse (A few thousand volts.) on the external wire. It then discharges the energy stored in a capacitor which produces the flash. You can get a good idea of the flash energy from the value of the capacitor (Which will probably be the largest capacitor in the unit and the voltage to which it is charged. ( This will probably be about 300 to 400 volts.) The energy stored in the capacitor is 1/2 (C x V^2) (Capacity in Farads) I suggest that you start fault finding by checking that the capacitor is being charged. If it is not look for a fault in the inverter circuit. If it is being charged then look for a fault in the trigger generator circuit.

Les.
 

MrChips

Joined Oct 2, 2009
21,133
Is there any way I can measure it using a multimeter to find any specs for a replacement?
How do you know that the flash tube is at fault?
It is more likely the up-converter circuit that is bad.
Check the DC voltage across the storage capacitor.

Careful. There is about 300V in there.
 

LesJones

Joined Jan 8, 2017
2,639
I can't see any components on the board that look like a step up converter (Inverter.) I would expect a small transformer and a trigger coil which will be connected to the wire that is around the outside of the tube. What is the value of the black electrolytic capacitor and its rated working voltage ? From the size of the capacitor it looks like quite a low power flasher. What is it used for ? If the flash does not need to be short duration (About 1 mS) then you may be able to build a unit using an LED so that the peak power was less but the duration longer.

Les.
 

MrChips

Joined Oct 2, 2009
21,133
What is the capacitance and voltage written on the capacitor?

I am expecting to see something like 10μF 450V written on it.
 

MrChips

Joined Oct 2, 2009
21,133
I can't see any components on the board that look like a step up converter (Inverter.) I would expect a small transformer and a trigger coil which will be connected to the wire that is around the outside of the tube. What is the value of the black electrolytic capacitor and its rated working voltage ? From the size of the capacitor it looks like quite a low power flasher. What is it used for ? If the flash does not need to be short duration (About 1 mS) then you may be able to build a unit using an LED so that the peak power was less but the duration longer.

Les.
The white square object in the middle of the board is the step-up transformer.

Klemmfix makes flashing red safety lights,
http://www.klemmfix.com/Products/Roadhazardwarninglamps/Roadhazardlamps-219
 

Dodgydave

Joined Jun 22, 2012
9,166
I can't see any components on the board that look like a step up converter (Inverter.) I would expect a small transformer and a trigger coil which will be connected to the wire that is around the outside of the tube. What is the value of the black electrolytic capacitor and its rated working voltage ? From the size of the capacitor it looks like quite a low power flasher. What is it used for ? If the flash does not need to be short duration (About 1 mS) then you may be able to build a unit using an LED so that the peak power was less but the duration longer.

Les.
I'm just wondering if the Silver Square component (with two rows of 5 pins) is a Transformer of some type,,failing that I'm as baffled as you are Les...
 

Thread Starter

Feinberg

Joined Dec 14, 2019
15
Theres strangely nothing written on it except for :
F&T Logo
84325
Typ A E
IEC 60 384-4
H3
It seems to be a "Fischer & Tausche" capacitor. They also provide custom capacitors. I can't find anything on their site with the provided information on the cap.
 
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