lamp Touch Sensor boards comparison

[iceblink]

Hi, hope this 1st post is ok and in the proper section. 

I have recently replaced a blown touch sensor in a lamp with a cheap generic model from ebay but I am a little worried that the cheap ebay replacement may not be safe. The replacement is on the left in the photo (

) and the old touch sensor, which blew, is on the right. The old one looks to have thicker wiring and better quality components (but it blew anyway) - can anybody advise if there are major safety issues I should be aware of. (The wire colours do not match between the two sensors, but the wiring diagrams seemed identical, just needed to switch around the colours, I can post the wiring diagrams if that would help)

[SeanB]

Old sensor likely has only a blown triac, which is easy to replace. Likely blew with a lamp failing as well.

[iceblink]

You mean that little 3-pronged black component? It has part number BT131 09 - can't find the exact part number in the uk after a quick search - I guess 09h is the same.

If it's just a few pence I'll try replacing it

(and yes, the sensor blew when I tried to remove an old bulb without switching off the power - duh!)

[SeanB]

BT131 triac, A little 600V 1A triac.

http://www.nxp.com/documents/data_sheet/BT131-600.pdf

The 09 is likely a manufacturer batch code. So long as when it died it did not kill the controller micro it will work with just a replacement. When it failed I guess the lamp was on all the time, or did you blow the little device open or blow a track off the board.

[iceblink]

Thanks, I can get one of those for 99p, but will probably wait until the replacement fails and then try a repair. When it failed it was plugged into the power socket, but the bulb had blown, I unscrewed the bulb and there was a little spark when I did this - but i suppose it could have failed when the bulb blew, I'll never know. There is no sign of any damage on the board, I assume it is a failure of one of the more delicate components.

I was wondering what the big copper coil and the large yellow cubic component were for on the older board - and that quality looking shiny blue capacitor? The components on the replacement board all look cheap in comparison, but the replacement has been working finr for over a week. (Note this touch sensor has 3 levels of brightness)