#### stuncer

##### Newbie

Hello

I am trying to set up a circuit to run a 1.5KVA three-phase motor in a standard way. Unfortunately, I am not very knowledgeable about power switching as I have been working on logical cards and mcu software until now.

Although I spent the last few days to find the relevant resistor and capacitor values, I could not reach the result.

I put a lot of effort into the training videos from the application notes I read.

AN-3003 I found a formula for R1 on page 4. But I couldn't understand where he got the 1.2A value in that formula (If it's "Peak Repetitive Surge Current" in MOC3011's datasheet, it says 1A)

Also, there is no R2 in my drawing, according to that example, should the sum of R1+R2 be 180 ohms?

There is also a concept like dv/dt that I still haven't been able to solve clearly.

Some application notes that I'm trying to understand

onsemi . com/pub/collateral/an-3003.pdf

onsemi . com/pub/collateral/an-3008.pdf

st . com/resource/en/application_note/an4993-how-to-implement-a-scr-or-a-triac-in-a-hybride-relay-application-stmicroelectronics.pdf

I would be grateful if anyone can help me determine the values I need ( R1, R2, R3, C1, C2) or provide a source that even someone at my level can understand.