charging station / wallbox hardware basics

[raysunwong]

Sorry for asking very basics questions, have been reading up on the GitHub repo about modifying the modem.
Currently i have got a TP-Link PA4010P v5.0 (UK plug), the live and neutral pin on the PCB seems to be injection moulded into the plastic housing, preventing me from disassembling it.
I see from the pictures from the repo the mains part has been removed, was it just cut off from the PCB with a dremel? I'm worried the layers of PCB would short together and interfere with the communication and wanting to know how you modified it.
Thanks a lot in advance.

[uhi22]

Could you share a photo of this situation? I would assume cutting the PCB is not necessary. Either desoldering the connection from the PCB, or cutting the metal beside the PCB with a dremel should be fine.
[Edit] If your PCB is the same as here: https://github.com/uhi22/pyPLC/blob/mas ... a4010p-v50 it is safe to cut the PCB with a dremel, too, at the same positions to not destroy too much.

[raysunwong]

To take the PCB out I think I have to remove the AC pins (Pass thru plug so the pin at the bottom are holding it in).
There are two ways of doing it I think.
a) Destroy the plastic casing and extract the PCB that way
b) Use a Dremel and cut the PCB off right below the AC pins

Any ideas will be appreciated

[jrbe]

They assembled it somehow. It doesn't look like a mold in place situation from the picture at all.
The shrouded one needs better pictures. They connected it / trapped it in there somehow. It's it soldered?
Maybe a small torch to heat the terminal from the top to melt the solder of it is?

[raysunwong]

They assembled it somehow. It doesn't look like a mold in place situation from the picture at all.
The shrouded one needs better pictures. They connected it / trapped it in there somehow. It's it soldered?
Maybe a small torch to heat the terminal from the top to melt the solder of it is?

upon further inspection, I suspect the solder connection at the bottom of the top AC pin is maybe connected to the bottom AC pin. I will try to unsolder that and post some update later.

[uhi22]

If you do not need the plastic housing anymore, just dremel it away (e.g. at the green lines), maybe this reveals some snap-in thingies below the PCB.
If nothing helps, you can dremel the housing and PCB on the blue line.

[raysunwong]

A question regarding op-amp selection.
On the BOM it stated to use the LF355 Op-Amp, is it ok for me to substitute it with the LF356N. (355 dont seemed to be available in the UK and i dont fancy buying potentially fakes on ebay)
I have skimmed through the datasheet, it seems like the difference is just power/voltage rating and it seems 356 is rated above 355 so it should be compatible?
Any help would be much appreciated, thank you!

[uhi22]

LF356 should be ok. The only concern is the output voltage swing, WE need nearly rail to rail, which does neigther the 356 nor the 355 advertise. So just give a try and look on the scope.

[raysunwong]

LF356 should be ok. The only concern is the output voltage swing, WE need nearly rail to rail, which does neigther the 356 nor the 355 advertise. So just give a try and look on the scope.

Thanks for the advice, i have not got all the components together yet, shall update the homeplug situation when i get my stripboard and other random passive components from work (Very lucky my work has top notch fully equipped electronics lab haha)

[raysunwong]

If you do not need the plastic housing anymore, just dremel it away (e.g. at the green lines), maybe this reveals some snap-in thingies below the PCB.
If nothing helps, you can dremel the housing and PCB on the blue line.
image.png

To provide an update on how to disassemble the UK version of the PA4010P, desolder the two solder join below the live and neutral connection. The bottom socket is injection molded into the bottom case, the solder joint connects it to the PCB.

Housing

PCB