Sorry but without a schematic it is a big ask for anyone to spend their time reverse engineering your PCB just to check that you have connected a solid state relay correctly.

Hiding the prefixes is somewhat less than helpful too.

Especially since it then hides the fact that all four of the SSRs have the same prefix.

Please see:

https://easyeda.com/forum/topic/How-to-ask-for-help-and-get-an-answer-71b17a40d15442349eaecbfae083e46a



In particular please read:

"The best way to design a PCB in EasyEDA" in (2.2) in (2) in the link above.

thanks for your valuable comments

@andyfierman

Thanks for your comments. I have redesigned and added a schematic for your kind review.

https://easyeda.com/editor#id=|0167615896994ea48c8f0886852af08b

U3 SSR is missing.

The link to the datasheet in LCSC.com page:

https://www.lcsc.com/product-detail/Photoelectric-Thyristor-Solid-State-Relays_Omron-Electronics-G3MB-202PL_C48654.html



is useless because it does not point to a datasheet for the specific part that they stock.

The LCSC.com page is also useless because it does not clearly specify the operating voltage of the part. The only indication is the reference to 12VDC in the photograph but this should not be relied upon. You will have to either check with LCSC what the operating voltage is or source the part from somewhere else that specifies it properly.

Here's a more useful datasheet for the SSR G3MB-202P series parts;

https://docs.rs-online.com/db5e/0900766b8002f991.pdf



Please read it very carefully.

Note that the LCSC page refers to a G3MB-202PL part but the symbol you have used is for a G3MB-202P.

Also, check that the footprint that you have used is correct for the schematic symbol and therefore the part that you are calling up from LCSC.com (C48654).

You have the polarity of the input control voltage connected correctly but you have not shown that the voltages of DC+, DC3+ and DC4+ are.

You have also not shown that the voltages applied to CH1, CH2, CH3 and CH4 are.

What is the purpose of the diode in series with each control input transistor emitter?

Have you allowed for the 0.7V plus transistor Vce_sat voltage drop in the voltage applied to the SSR control inputs?

@andyfierman

@saqeb

Dear  andyfierman,
I am very thankful for your kind review and suggestions. Sorry for my basic questions, but I am a software engineer, and its my first time designing a board. I hope you will understand.

1. G3MB-202PL and G3MB-202P have the same footprint. I will source them locally. The rest of PCB SMT will be done by jlcpcb.
2. DC3+ and DC4+ is the 5VDC from separate Arduino-like device, So I keep them separate.
3. CH1, CH2, CH3, and CH4 are 3.3V VDC pulses of Arduino-like board.
4. What is the purpose of the diode in series with each control input transistor emitter?
   1. To protect 5VDC of microcontroller.

5.Have you allowed for the 0.7V plus transistor Vce_sat voltage drop in the voltage applied to the SSR control inputs?
I don't know about this :-(

@saqeb,

Some important points:

• Please be aware that the G3MB-202P DC5 solid state relay is obsolete.
• Using a PNP transistor as a high side switch supplied from +5V and switched from 0V to +3.3V in the configuration that you have used becomes unreliable at high ambient temperatures.
• Since it would seem that you wish to switch a load at mains voltages of somewhere between 100V and 264V AC it is important that you design the PCB to include suitable connectors and appropriate high voltage creepage and clearance distances and possibly high voltage warnings markings. You have however removed access to the PCB design so it is no longer possible to comment on its suitability.

You appear to be doing this design for some sort of commercial venture so for a fee I can offer design and design review services through signality.co.uk.

For more information please contact me via the email address on my website.