How to Repair LED Lamps
The LED
circular lamp in our dining room went off suddenly. This is after about 2 years
in operation. One set
of two LEDs were found faulty. This
article
serves to share how to troubleshoot and repair this LED module. The
procedures described here can be used also on other types of LED lamps
How LED Lamp Works?
Unlike
normal fluorescent lamp, LED lamp does
not have fluorescent tube nor ballast; instead, it has the following components
1. The LED element;
2. The LED driver;
3. The Aluminium heat sink.
As current
flow through the LEDs, it causes the
LEDs to give out lights. Depending on the
size and power of the lamp, a LED driver can supply different wattages to several LEDs arranged in series. In
this case for the 18 watts circular lamp, the driver will supply 48
Volts to the LEDs. Each LED will operate at around 3 to 3.6 Volts and
consume around 0.5 watts of power. There are about 36 LEDs in this 18
Watts lamp. The LEDs are arranged in an array
as illustrated in the following
What can usually go wrong?
The LED
driver consists of very few components as shown.
It is unlikely to have broken down as it is quite robust and reliable. Most likely the LEDs are the ones at fault.
What’s Needed?
There is no
special and expensive tools needed.
Description
|
Remarks
(doubleclick to enlarge
pictures)
|
1. Two numbers of 1.5 Volts AA or AAA battery, improvised as LED tester
|
Solder
them up in series as shown
 |
2. LED elements
|
They are
available from various online website such as AliExpress. 100 piece of common type of LEDs cost less
than USD$1/=
 |
3. Soldering tools
|
Soldering
irons and solders
|
Repair Step by Step
Description
|
Action
|
Remarks
(doubleclick to enlarge
pictures)
|
1.
Inspection & testing
|
1. Go through by inspecting the LED one by
one.
2. One could also light up the LED by touching their ends using the improvised LED tester.
The pair of LED should light up unless they are faulty.
|
Faulty
LED can be easily spotted by its burnt mark as shown
 |
2. Unsoldering
|
1. Unsolder and remove the faulty LED from the
board using the soldering iron.
2. Carefully solder the new LED after having
identified the locations of the Anode and Cathode and place it back into the correct position
|
The
cathode is identified by an additional plate at the end of the tips as shown
 |
3. Final Testing
|
1. After soldering, test the repair
using the improvised LED tester.
|