This will be the first real post since December 4, 2019 it looks like!
There are tools now that apply a pulse of voltage to short across a non-working LED. I don't have one, but I plan to try that method. I am a little concerned about the possibility of damaging adjacent good LEDs.
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My favorite tool for troubleshooting all but the simplest non-working mini LED light strings is a special probe I made. This method is not for anyone without an electrical background and experience, as it could expose the user to hazardous voltages. It can sometimes trip a GFCI, so it may have to be used on a non-GFCI receptacle. It also takes quite a bit of time and is very annoying! This probe is made from a length of flexible insulated wire, a 10,000 Ohm, 3 Watt resistor and a short piece of stiff bare wire covered with insulation to within about 1/4" of the end. The free end of the wire gets connected to a ground like a water pipe. The working end contains the resistor followed by the stiff wire sticking out. The whole working end should be covered with heat shrink tubing except the last 1/4" of the stiff wire at the end of the resistor. Using a binary search algorithm, stick the probe in a single removed led in a non-working segment of a light string. If one half of the segment doesn't light, flip the plug. If it still doesn't light, there is more than one bad LED and/or the fuse is blown or a wire broken. Regardless, continue working toward the non-working end (or ends) pulling out a LED at the midpoint of the remaining section to be tested, until some at one end or the other are seen to work. It might be a good idea also to modify the algorithm by initially testing the second LED in from each end of the segment, as the very first LED often has a problem with conductivity through the socket and LED. Whenever a bad LED is found replace it. Work your way back towards the bad end of the segment until the whole thing works.
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My favorite tool for troubleshooting all but the simplest non-working mini LED light strings is a special probe I made. This method is NOT for anyone without an electrical background and experience, as it could expose the user to hazardous voltages!! Do not touch anything grounded while testing powered light strings, with or without this probe, including resting your knee on wet soil!! This probe method can sometimes trip a GFCI, so it may have to be used on a non-GFCI receptacle. It also takes quite a bit of time and is very annoying!
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To keep from tripping GFCI receptacles, the resistor can be set much higher so that the current can never exceed about 4 milliamps. This value would be 39,000 Ohms or higher. The resistor power only needs to be 1W at this lower current. The down side versus the lower 10,000 Ohm resistor value that can approach 20 milliamps, is that at the higher resistance the LEDs get pretty dim when testing near the far end of a segment and most of the LEDs are in the circuit.
+
This probe is made from a length of flexible insulated wire, a 10,000 Ohm, 3 Watt resistor and a short piece of stiff bare wire covered with insulation to within about 1/4" of the end. The free end of the wire gets connected to a ground like a water pipe. The working end contains the resistor followed by the stiff wire sticking out. The whole working end should be covered with heat shrink tubing except the last 1/4" of the stiff wire at the end of the resistor. Using a binary search algorithm, stick the probe in a single removed led in a non-working segment of a light string. If one half of the segment doesn't light, flip the plug. If it still doesn't light, there is more than one bad LED and/or the fuse is blown or a wire broken. Regardless, continue working toward the non-working end (or ends) pulling out a LED at the midpoint of the remaining section to be tested, until some at one end or the other are seen to work. It might be a good idea also to modify the algorithm by initially testing the second LED in from each end of the segment, as the very first LED often has a problem with conductivity through the socket and LED. Whenever a bad LED is found replace it. Work your way back towards the bad end of the segment until the whole thing works.
+
+
To keep from tripping GFCI receptacles, the resistor can be set much higher so that the current can never exceed about 4 milliamps. This value would be 39,000 Ohms or higher. The resistor power only needs to be 1W at this lower current. The down side versus the lower 10,000 Ohm resistor value that can approach 20 milliamps, is that at the higher resistance the LEDs get pretty dim when testing near the far end of a segment and most of the LEDs are in the circuit.
.....
I've been repairing visibly damaged strings these days using solder seal type butt splices. It's a lot faster than glue-filled heat shrink tubing applied on top of a standard soldered splice. Unfortunately they seem to only be available in clear, so time will tell how well they hold up to the UV from the sun. (That makes sense, because opaque tubing would make it really difficult to align the wires correctly! I suppose black polyolefin heat shrink tubing could always be shrunk down on top of the repair as a second layer, assuming there's enough wire to work with.) Also the bare copper strands have to be reasonably shiny to get the solder to wet them upon heating.
A heat gun, lighter or even small butane torch applied carefully will set them just fine.
This will be the first real post since December 4, 2019 it looks like!
There are tools now that apply a pulse of voltage to short across a non-working LED. I don't have one, but I plan to try that method. I am a little concerned about the possibility of damaging adjacent good LEDs.
-
My favorite tool for troubleshooting all but the simplest non-working mini LED light strings is a special probe I made. This method is not for anyone without an electrical background and experience, as it could expose the user to hazardous voltages. It can sometimes trip a GFCI, so it may have to be used on a non-GFCI receptacle. It also takes quite a bit of time and is very annoying! This probe is made from a length of flexible insulated wire, a 15,000 KOhm, 2 Watt resistor and a short piece of stiff bare wire covered with insulation to within about 1/4" of the end. The free end of the wire gets connected to a ground like a water pipe. The working end contains the resistor followed by the stiff wire sticking out. The whole working end should be covered with heat shrink tubing except the last 1/4" of the stiff wire at the end of the resistor. Using a binary search algorithm, stick the probe in a single removed led in a non-working segment of a light string. If one half of the segment doesn't light, flip the plug. If it still doesn't light, there is more than one bad LED and/or the fuse is blown or a wire broken. Regardless, continue working toward the non-working end (or ends) pulling out a LED at the midpoint of the remaining section to be tested, until some at one end or the other are seen to work. It might be a good idea also to modify the algorithm by initially testing the second LED in from each end of the segment, as the very first LED often has a problem with conductivity through the socket and LED. Whenever a bad LED is found replace it. Work your way back towards the bad end of the segment until the whole thing works.
+
My favorite tool for troubleshooting all but the simplest non-working mini LED light strings is a special probe I made. This method is not for anyone without an electrical background and experience, as it could expose the user to hazardous voltages. It can sometimes trip a GFCI, so it may have to be used on a non-GFCI receptacle. It also takes quite a bit of time and is very annoying! This probe is made from a length of flexible insulated wire, a 10,000 Ohm, 3 Watt resistor and a short piece of stiff bare wire covered with insulation to within about 1/4" of the end. The free end of the wire gets connected to a ground like a water pipe. The working end contains the resistor followed by the stiff wire sticking out. The whole working end should be covered with heat shrink tubing except the last 1/4" of the stiff wire at the end of the resistor. Using a binary search algorithm, stick the probe in a single removed led in a non-working segment of a light string. If one half of the segment doesn't light, flip the plug. If it still doesn't light, there is more than one bad LED and/or the fuse is blown or a wire broken. Regardless, continue working toward the non-working end (or ends) pulling out a LED at the midpoint of the remaining section to be tested, until some at one end or the other are seen to work. It might be a good idea also to modify the algorithm by initially testing the second LED in from each end of the segment, as the very first LED often has a problem with conductivity through the socket and LED. Whenever a bad LED is found replace it. Work your way back towards the bad end of the segment until the whole thing works.
+
+
To keep from tripping GFCI receptacles, the resistor can be set much higher so that the current can never exceed about 4 milliamps. This value would be 39,000 Ohms or higher. The resistor power only needs to be 1W at this lower current. The down side versus the lower 10,000 Ohm resistor value that can approach 20 milliamps, is that at the higher resistance the LEDs get pretty dim when testing near the far end of a segment and most of the LEDs are in the circuit.
.....
I've been repairing visibly damaged strings these days using solder seal type butt splices. It's a lot faster than glue-filled heat shrink tubing applied on top of a standard soldered splice. Unfortunately they seem to only be available in clear, so time will tell how well they hold up to the UV from the sun. (That makes sense, because opaque tubing would make it really difficult to align the wires correctly! I suppose black polyolefin heat shrink tubing could always be shrunk down on top of the repair as a second layer, assuming there's enough wire to work with.) Also the bare copper strands have to be reasonably shiny to get the solder to wet them upon heating.
A heat gun, lighter or even small butane torch applied carefully will set them just fine.
This thread is getting taken over by spammers...
This will be the first real post since December 4, 2019 it looks like!
There are tools now that apply a pulse of voltage to short across a non-working LED. I don't have one, but I plan to try that method. I am a little concerned about the possibility of damaging adjacent good LEDs.
My favorite tool for troubleshooting all but the simplest non-working mini LED light strings is a special probe I made. This method is not for anyone without an electrical background and experience, as it could expose the user to hazardous voltages. It can sometimes trip a GFCI, so it may have to be used on a non-GFCI receptacle. It also takes quite a bit of time and is very annoying! This probe is made from a length of flexible insulated wire, a 15,000 KOhm, 2 Watt resistor and a short piece of stiff bare wire covered with insulation to within about 1/4" of the end. The free end of the wire gets connected to a ground like a water pipe. The working end contains the resistor followed by the stiff wire sticking out. The whole working end should be covered with heat shrink tubing except the last 1/4" of the stiff wire at the end of the resistor. Using a binary search algorithm, stick the probe in a single removed led in a non-working segment of a light string. If one half of the segment doesn't light, flip the plug. If it still doesn't light, there is more than one bad LED and/or the fuse is blown or a wire broken. Regardless, continue working toward the non-working end (or ends) pulling out a LED at the midpoint of the remaining section to be tested, until some at one end or the other are seen to work. It might be a good idea also to modify the algorithm by initially testing the second LED in from each end of the segment, as the very first LED often has a problem with conductivity through the socket and LED. Whenever a bad LED is found replace it. Work your way back towards the bad end of the segment until the whole thing works.
.....
I've been repairing visibly damaged strings these days using solder seal type butt splices. It's a lot faster than glue-filled heat shrink tubing applied on top of a standard soldered splice. Unfortunately they seem to only be available in clear, so time will tell how well they hold up to the UV from the sun. (That makes sense, because opaque tubing would make it really difficult to align the wires correctly! I suppose black polyolefin heat shrink tubing could always be shrunk down on top of the repair as a second layer, assuming there's enough wire to work with.) Also the bare copper strands have to be reasonably shiny to get the solder to wet them upon heating.
A heat gun, lighter or even small butane torch applied carefully will set them just fine.