Miele Vacuum Cleaner Problem

[Sefton Dave]

Hi all, this is my first post in the hope that someone may be able to me and maybe educate me!

Our Miele Vacuum Cleaner came to a sudden stop the other day. Looking round on the internet I found that a common problem with this make is that the centre pin of the onboard triac blows off the circuit board. On inspection I can see that the centre pin of the BTB16-600BW triac is not connected to anything.

My problem is that I cannot find where it was connected, or maybe it is wired correctly, just using 2 pins?

Every circuit that I look at uses the 3 pins, A1-A2-Gate

Thanks. Dave.     

[JimmyJo]

The tab of a TO220 package and the center pin is the same piece of metal.  In this design, it looks like they are using the tab connection, going thru the heatsink.

It also looks like there is a cracked joint on pin 3(right most pin when part numbers are in the correct orientation) of the triac.  If you have a soldering iron, reflow all joints with a bit of flux.