Pyranometer SR05-D2A2 Connection Questions

Other Hardware Sensors
1

Hello,

I have this Hukseflux SR05-D2A2 pyranometer thermal sensor, that support Modbus communication through a TTL interface and I would like to connect it to an Arduino, but I have some doubts about the wiring, so I’m asking for your help.

My main concern is related to the TTL communication protocol. I’ve used some RS485-type sensors before that required an additional RS485-to-TTL converter to connect to a microcontroller. In this case, since the protocol is already TTL, do I just need to connect the RX and TX of the pyranometer directly to microcontroler? Or do I still need an additional RS232 converter?

Another question I have is about the wires (pg 37):

image

My interpretation is to connect the power supply: positive to Brown and negative to Blue. Then, connect Black, White, and Grey to the microcontroller's GND, TX, and RX, respectively. Does this seem correct? And what about the Yellow (shield)? Should I connect it to the microcontroller's GND as well?

In the datasheet, there is this warning: "If the TTL device to which SR05-D2A2 is connected requires external power, this power must be drawn from a separate power supply with a floating potential with respect to the power supply used by SR05-D2A2."

So, I need two different power supplies—one for the pyranometer and another for the Arduino? Is that correct?

Thanks

2

So far your description is 100% correct. Including NOT connecting the shield to the Arduino ground. Connect the shield to the 5 to 30 volt supply ground.

3

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.