💬 In Wall AC/DC Pcb (with Relay) for MySensors (SMD)

[sundberg84]

@sineverba it is much to learn and instead of me trying to make a half ok job I would suggest you search SSR vs mechanical relay. I think greatscott did a great Youtube video about it.

[rzylius]

hi, I get constantly messages Arduino: 1.8.5 (Linux), Board: "Arduino Pro or Pro Mini, ATmega328P (5V, 16 MHz)"
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0xde
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x4c
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x9d
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0xaa

is this hardware problem? I select Arduino Pro Mini board setting with AVRISP mkII programmer. are these ok?

[sundberg84]

@rzylius could be a bootloader or hardware settings. I would check the reset resistor. Do you know which bootloader is on or did you manage to upload one though iscp header?

[rzylius]

@sundberg84 said in 💬 In Wall AC/DC Pcb (with Relay) for MySensors (SMD):

header?

No, I did not. I used to work with arduinos, so this is the first time I bought and try mega328p. could you advise where to find a resource with step-by-step instructions on that?

[rzylius]

@sundberg84 , sorry, I meant I did not burn the bootloader and was not aware of that.

Did you mean "reset capacitator", not resistor?

And on that note, am I right that reset to iscp should go to DTS contact?

thanks for help.

[sundberg84]

@rzylius - some chip have bootloader on it already, some dont. Depends on where you buy it - but the only way to be able to upload through ftdi is if there is a bootloader.

I meant reset capacitor :) Thanks! Yes, reset should go to DTS.

[nekitoss]

I was wondering if 73 defree for thermal fuse is long-operating temperature or blow temperature? (i looked at well-known for you all test, where it heated around 63 degrees at 1hour rated load)
In any case long-time 73C thermal fuse will have around 100C blow temperature (looked at my local store). I'm asking because on ebay link they are rated as 240C...

Other moment i woul like to aware - (as you know, not shure about others) - there are counterfeit G3MB-202P relays everywhere, which are officially discontinued March 2011 (!).
You correcly put there a G3MC-202P relay. But someone may not notice those difference in one letter and buy a counterfeight relay in local store...
Also i was sitting and reading a lot about safety, especially about counterfeits in this high-voltage parts, and found this picture which shows, what happened with those (i think, because of post date)bad relay with 1 Amp load with incandescent lamps.
That is also a problem of all SSR relays - that they heat. So i was wondering how much heats original relay and if it is good idea and possible (i understand that it is very hard to update such small pcb) to move thermal fuse between relay and HLK-PM01, so it can protect both? Or put it verticall (not shure about clearance and creepage in this case) in corner between them.

I was dissapointed about price of relay, especially against counterfeit, but safety is worth it! Also you can make same simple sheme as inside relay (even from datasheet on moc30xx), but you must know a lot in electonics to make it as safe as sealed factory relay i think (but in oppsite in such shemas over internet ushually resistor are recommended up to 2Watt (for 16A shemas) while smd resistors have much less watts...).
Also it would be nice to add in description to what this relay can be applied to. Because not everyone may understand that incandescent lamps at start have bigger current, and at the moment filament is broken a short-ciruit with arc appears. And ssr relays usually die at short-circuit and you need fast fuse to save them, but they are expensive... And you should not use it with motors, etc or use with lower ratings...
I really think they must be warned, even shortly.

And only 100% way to buy original HLK-PM01, is to buy from manufacturer site. but i'm wondering how much will cost shipping. Wholesale price (which is in basket) is even lower than ebays. At the moment it is 2.50$

Sorry for so much text, i may somewhere be wrong, feel free to correct me and discuss. But when it is about safety - i cannot stand aside.

[sundberg84]

@nekitoss Hi! Thanks for you input.
CUrrently I do not have any plans to change anything on this board. Its created in Eagles CAD which i havent used since i moved to Kicad. I dont even have it installed anymore. The good thing is that all files are included so you can download and change for yourself.

[jeremushka]

Nice project :). What is the maximum load the system can accept? 16A 1500W?

[sundberg84]

@jeremushka - if you mean through the relay, it depends on which one you choose - check the datasheet for that. I used a g3mc-202pl and this is no more than 1A-2A

[jeremushka]

@sundberg84 thank you. Yes i mean through the relay i need to switch a water heating system 2500W. I need a relay capability for 20A to secure the interface.
I don't know much for this kind of relay i need to modify the schematic of a 10A relay switch. Such as different optocoupler or transistor.. do you have any idea?

[sundberg84]

@jeremushka - sorry, i dont know enought about high currents like that to help.

[jeremushka]

@sundberg84 no problem. I will study about that. Thanks for you reply.

[gohan]

Do you really need a compact device?