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LED Bothroom Mirror

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jada88

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Hi
Installed a LED bathroom mirror with infra-red switch a couple of years ago, worked fine till a week ago. Problem switches on ok but will not switch off. Took the front off to see what units were inside the switch is connected to a JN2101R transformer (sealed unit) went to web site but I cannot find the spec sheet. Any ideas or suggestons will be appreciated.

jada88
 
connected to a JN2101R transformer
That is not a transformer, its a remote controlled dimmer module.
It may have a bad triac.
You may have to replace it.
 
I dont understand why a LED light would have an AC controller.
Are the lamps AC or does it have another module in it?
 
Hi 4pyros
The mirror does have another module in it, I take it that it is a LED driver. The JN2101R unit has the following stamped on it 220-250AC 10-300W. Is this information helpfull.

jada88
 
The remote controlled dimmer module may have a bad triac. Thay normaly go bad staying on.
You may have to replace it.
 
Hi
4pyros
Many thanks for your advice. I will take it apart if possible and see if I can repair it.

jada88
 
Hi 4pyros
Following on from my previous post I have taken apart the JN2101R unit. There does not appear to be a triac in the circuit / PCB. I have looked on line for a replacement , and spent a considerable amount of time looking for a circuit to make to replace this unit to no avail. I have no problem making PCBs. This unit feeds a electronic led converter. Do I assume that the sensor is a infrered source and sensor unit? It hase 5 wires connected to the PCB. Here are some pictures of the PCB and sensor.View attachment 66748 View attachment 66749 View attachment 66750
 
It looks like there maybe some bad solder joints on that board. Can you solder?
Try and fix the solder joints on the bigger parts with the thru hole leads.
Some really bad ones are next to R16 and ZD3 on the back.
Look just above C5, looks like that lead may fall off.
Re-solder the board and try again.
 
Checked out the solder joints under a strong magnifying glass and they seem to be good. Put the unit back into case and the unit worked intermittently. Not very happy about putting it back in the mirror, and would like to find a circuit that uses a triac. If you have any suggestions I would appreciate your input.
 
Checked out the solder joints under a strong magnifying glass and they seem to be good.
Resolder them anyway and it may work fine.
Sometimes it is hard to see a bad solder joint, but there are defiantlyl some questionable ones on that board.
 
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Check out the image edit.
The joint circled appears to be the plus of a filter cap and cathode of zd1.
 
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You will need to determine if it's the relay is sticking, the electronics is bad or the switch is flaky.

Since it is intermittent and a meter may take a while to see.

The relay is 12 volts. Putting a LED and 680 to 1000 ohm resistor in series across the relay coil pins or D4 on the back side will tell you when the relay is energized.

If the led is not lit but the fixture light is, then the relay contacts are sticking.

cheers
 
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Could be the relay contacts are pitted as a result of arcing and stick closed on occasions. I had that happen to a security light.
You could replace that relay with a solid-state relay or with an opto-triac (possibly driving a slave triac having greater power handling ability).
 
Relay seems to be ok, I could hear it clicking on and off, and checked with a meter at the output, when it was working. Ran the meter over the PCB and I was suprised to find mains voltage at the sensor switch, and it appears that the switch may be the problem working sometimes then not.
What type of sensor switch is it? Can you tell from the image I posted.
 
I could hear it clicking on and off
That doesn't necessarily mean the contacts aren't sticking. What you hear is probably the armature hitting a stop; not the contacts hitting something.
I was suprised to find mains voltage at the sensor switch
You shouldn't be surprised. The whole circuit has no mains isolation transformer. C1 and its mate are a current source for the circuit.
 
Hi alec_t
I did connect a meter to the output (red wires) and when it was working it was switching on and off.
 
when it was working it was switching on and off.
More importantly, what was it doing when it wasn't working? Could you still hear the relay clicking then? Were there still volts/no volts across the relay coil when it should have been switching?
 
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