Hello, I have designed this circuit to control a FOTEK SSR-40DA using an ESP32 GPIO pin. This design is intended for mass production, and I would appreciate any advice or suggestions to optimize it before proceeding. My ultimate goal is to control 4kW 220V heating element. Control means just turn ON…

Could You post a link to the SSR datasheet?

For production work, R1 and R4 should be the same resistive value if the wattage are the same. Can you put the LED in series with the LED in the Fotek SSR?

Can you please explain the reason for making R1 and R4 the same? All resistors are 0.25W

D1 is unnecessary because of the optocoupler at the low voltage side. Right? Yes, some safety should have been there. As FOTEK SSR will not be a part of the PCB I was thinking of placing Fast-Blow Fuse of lets say 12V and 500mA on pin 1 of CN7 (connector). This will protect the low voltage side if …

SSR-SSR-DA (1).pdf (2.0 MB) Attached is the datasheet that is available on their website. The weblink is FOTEK

You don't need any of that circuit. You can drive the SSR directly from an ESP pin FOTEK also know as FAUX TEK [image]

[image] ssohaib: Can you please explain the reason for making R1 and R4 the same? All resistors are 0.25W Sure! Part of the cost to build a circuit board by hand or by machine is the number of different components that must be inventoried and ensured that the proper value is placed in the p…

Seeking Feedback on ESP32-Based Circuit Design for Controlling FOTEK SSR-40DA

Projects General Guidance

anon85221860 January 4, 2025, 5:33pm 4

D1, R4 unnecessary, serve no purpose.
R5 no purpose
R2 no purpose
Missing: fire extinguisher (for rotten "Fotek" SSR)

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Seeking Feedback on ESP32-Based Circuit Design for Controlling FOTEK SSR-40DA

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