Hopefully I can recover everything if needed. Lost all my settings, but I'm having a backup of the old folder.
MODBUS POLL GITHIUB INSTALL
Today I removed my OpenPLC_v3 folder and did a fresh install (git clone. Is this limiting at 2400 baud and can cause connection timeouts? How often are the input registers of the energy counter read then? Each 50 ms or 250 ms? The task cycle is T#250ms for the temperatures and T#50ms for the GPIOs. The program running on the OpenPLC at the same time is fetching temperatures from two ESP8266 slaves per Modbus-TCP and some GPIOs on the RPi4. The cable-length is 2 m, 2 wires, shielded (but not connected to a common ground).
The SDM120M has 2400 baud (8N1) per default. I don't understand at the moment, what limits the size of usable registers to just around 12. To reach all parameters of the SDM120M I would need a size of more than 300 input registers in OpenPLC! For example, these are the addresses of the (16-bit) input registers: That is a problem, because the higher registers are unreachable then.
Modbus Read Input Registers failed on MB device SDM120M: Connection timed out Great!īut to my surprise I start to get connection timeouts to my modbus slave once I configure more than a size of around 12 Input registers in the Edit slave device window. I can read two Input Registers with node-red at the moment (voltage and current), so OpenPLC works generally. A Raspberry Pi4 with OpenPLC is connected with an SDM120M energy counter over an USB-to-RS485 adapter. I'm doing my first steps with Modbus-RTU.