LED Circuit

I have an inspection light that has several LED's in a 36" tube for inspecting inside cylinders. It works off a 12 V transformer. The light quit on me and when I opened it up there was a diode like component that was burned to a crisp in line with the LEDs. When I by-passed the burnt component the lights worked but flash on and off. Could someone tell me what the component is and where to buy a replacement?

by master302
April 21, 2018

2 Answers

Answer by mikerogerswsm

It may be a diode, for example a 1N4001 type, but you need to give more information, for example are the LEDs in series and what do you mean by 'flash'. It would be helpful if you could measure the input voltage and indicate the frequency, if any. mike

+1 vote
by mikerogerswsm
April 22, 2018

One amateur source is Mouser. Another is Farnell.

by mikerogerswsm
April 22, 2018

Answer by master302

The voltage is 12 V DC going into 12 LEDs wired in parallel. The diode like component is in series with the plus side before the LEDs. When by passed with a jumper wire the LEDs light up and flash on and off at about 1 sec. intervals. No components have any markings on them. The LEDs are bright white light.

+1 vote
by master302
April 22, 2018

Something strange here. The LEDs should take about 20mA each, so a dozen take only 250mA, which a 1N40001 should pass with ease. But the 1 second flash rate is odd. Perhaps the supply is doing funny things. There should be a current limiting resistor, either one for each LED (about 500 ohms) or one in the supply (about 40 ohms).

by mikerogerswsm
April 23, 2018

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