Hey,
My halogen lamp burnt and would like to replace the actual circuit with one that I could control remotely from an app or esp8266.
Can anyone help with this project if it is feasible? I would need some help designing the circuit as well.
Many thanks,
Did you figure out what it was that caused it to burn-out was?
Was it something to do with the circuit that you didn't post?
The picture kinda tells the story though. I don't think this device is really repairable! How/when did the leg get torn off the transistor?
I think that's a TRIAC, not a transistor. There's a G marking at one pin, no marking at other pins. I don't see a rectifier, I do see a 4A fuse and a 500W output, suggesting it's a 220V AC circuit. Probably a dimmer circuit similar to this one. The parts set is the same: two capacitors, inductor, DIAC (the blue part marked D, it looks like it has a double diode symbol under it), resistors. Probably a resistor that burned there.
Repairable? Maybe. Depends on what it was that caused that part to burn. That and the TRIAC need to be replaced at least. It is possible to make such a dimmer controlled by an Arduino or ESP8266 - you need to do zero crossing or peak detection on the AC line, and apply phase cutting. Not trivial, especially the hardware side due to the high voltages.
Hi,
Ops pic.
Is that dimmer designed for Halogen Lamps?
They have a very high inrush current even when phase controlled.
Tom... 
That looks like a board from a vacuum cleaner.
Did you make that 'halogen lamp' yourself ?
I assume you know that halogen lights have a much shorter life when dimmed.
Leo..
wvmarle:
I think that's a TRIAC, not a transistor. ...
(slaps forehead) yeah, of course - that makes sense. I'm most impressed with the exploded resistor, if it is a resistor that is! 
Part on the board is probably was a diac.
Leo..
I think the green component next to the coil is the diac (based on the marking D and the partly obscured printing under it), don't know why there would be two of those.
Looks like a conventional lamp dimmer circuit. If the triac failed in such away as to connect mains across the diac, burning out it's lead in the process, it's no wonder it blew that up too.
Don't bother to repair it - a domestic lamp dimmer is cheap.
Allan
Hi,
I used to fit some halogen mains powered lamps in my home, and they had a fuse link built in the glass envelope.
It was supposed to blow if a short or over heating occurred in the lamp, it seems this is not an uncommon occurrence with halogen filaments.
http://www.iloencyclopaedia.org/part-vi-16255/lighting/46/types-of-lamps-and-lighting
Tom...
