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Modbus Temperature Acquisition Sensor DS18B20 RS485 RS232 PLC Serial Protocol - Printable Version

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Modbus Temperature Acquisition Sensor DS18B20 RS485 RS232 PLC Serial Protocol - HelpMe - 11-21-2016

So Ive gotted a hold of this modbus temperature sensor off of ebay.
 
 
No where to be found anywhere on the internet is the Modbus register for this device, I have spent hours searching high and low to find it.
Having emailed all the sellers on ebay, only to either get no response or a reply in broken English. 
 
I destroyed the plastic housing trying to get at the PCB to see if there were any part numbers of manufacturing details but to no avail.
 
After a few hours of trial and error I was able to read a floating point value of “3” from register 30006, and that is it.
 
 
Anyone else out there seen one of these before or know who makes it?

Forgot to link to it

http://www.ebay.co.uk/itm/Modbus-Temperature-Acquisition-Sensor-DS18B20-RS485-RS232-PLC-Serial-Protocol-/330869940360


RE: Modbus Temperature Acquisition Sensor DS18B20 RS485 RS232 PLC Serial Protocol - Guest - 12-23-2016

Hi,

This is what I managed to get from the sensor:

All values are 16bit values and you can only request single value in one request. Default setting should be slave 1, 9600, 8, none, 1.
Temperature is register 2 function 4 (or 30002) value x100
Slave address is write only register 1 function 6
Baudrate is register 6 function 3 (or 6 for writing) value 3=9600, 4=19200
Parity is register 7 function 3 (or 6 for writing) value 0=none, 1=even, 2=odd

When you write you need to power cycle the sensor to apply new setting.

Hope this helps...


RE: Modbus Temperature Acquisition Sensor DS18B20 RS485 RS232 PLC Serial Protocol - Guest - 03-05-2017

(12-23-2016, 07:01 PM)Guest Wrote: Hi,

This is what I managed to get from the sensor:

All values are 16bit values and you can only request single value in one request. Default setting should be slave 1, 9600, 8, none, 1.
Temperature is register 2 function 4 (or 30002) value x100
Slave address is write only register 1 function 6
Baudrate is register 6 function 3 (or 6 for writing) value 3=9600, 4=19200
Parity is register 7 function 3 (or 6 for writing) value 0=none, 1=even, 2=odd

When you write you need to power cycle the sensor to apply new setting.

Hope this helps...

Hi

Good thing i checked back here,

just tried those settings and got it working, 

thanks very much