High Voltage Fan Control ( High Voltage Spikes,High Reliability)
Hello,
I'm building a Fan Control Circuit for controlling the speed of a 380V Fan.(380V RMS, ~540V Peak-max 150W) using a microcontroller.
My main circuit is something similar to this FreeScale Application note :
https://cache.freescale.com/files/microcontrollers/doc/app_note/AN3471.pdf
In my circuit, I have a different microcontroller, Optotriac and Triac. I can select the optotriac between MOC3082 or IL4208 (Both 800V).My main Triac will be BTA208X-1000 (1kv).
These components are currently used in our circuits and already available, so using them can be cost effective and more preferable than a new component unless we have to.
My Main problem is : This circuit will be used in an industrial place with working welding machines. Because of the effects of welding machines on main 3-Phase AC POWER, there is some spikes up to 1kv on AC-Line. I'm not sure if the optotriac can take this for long period and i couldn't find any 1kv optotriac. How can i protect the optotriac against these spikes? How can i increase my circuit's reliability?