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zegelin / samsung-hvac-mtqq

Bidirectional bridge between Samsung residential HVAC units and MQTT
MIT License
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RS485 USB Adapter #2

Open nicolaerosia opened 11 months ago

nicolaerosia commented 11 months ago

Hello,

[I have a Samsung NASA EHS]

I tried to connect to COM 2(F3/F4) using a cheap adapter which works OK on COM 1(F1/F2), https://www.okystar.com/product-item/usb-to-rs485-converter-oky3406-6/

Seems like the moment I connect both wires to the adapter, the wired controller shuts down (like it would cause a short circuit).

Any ideas? Can you please describe your setup?

What does A+ and B- mean? I connected A+ to F3 and B- to F4

Regards, Nicolae

nicolaerosia commented 11 months ago

Meanwhile I found out that F3/F4 is actually a PLC (Power Line Communication) :(

zegelin commented 11 months ago

I'm uncertain how the NASA units work sorry. I only have access to a non-NASA setup. On non-NASA F3/F4 are RS485 to the WRC.