SDI-12 measurements

The CS650 responds to SDI-12 commands M!, M1!, M2!, M3!, M4!, ?!, and I!. CS650 SDI-12 commands shows the values returned for each of these commands.

Establish SDI-12 communications using the SDI12Recorder() CRBasic instruction. See Data logger wiring for SDI-12 wiring details.

NOTE:

This section briefly describes using SDI-12 commands. Additional SDI-12 information is available at SDI-12 sensor support, www.sdi-12.org , or www.youtube.com/user/CampbellScientific .

CS650 SDI-12 commands

SDI-12 command
(“a” is the sensor address)

Values returned

Units

aM!

  1. Volumetric Water Content, q

  2. Electrical Conductivity, s

  3. Temperature

m3/m3

dS/m

°C

aM1!

  1. Permittivity, e

  2. Electrical Conductivity, s

  3. Temperature

 

dS/m

°C

aM2!

  1. Period, t

  2. Voltage Ratio, a

  3. Temperature

μs

 

°C

aM3!

  1. Volumetric Water Content, q

  2. Electrical Conductivity, s

  3. Temperature

  4. Permittivity, e

  5. Period, t

  6. Voltage Ratio, a

m3/m3

dS/m

°C

 

μs

aM4!

  1. Volumetric Water Content, q

  2. Electrical Conductivity, s

  3. Temperature

  4. Permittivity, e

  5. Period, t

  6. Voltage Ratio, a

m3/m3

dS/m

°C

 

μs

aM5! .. aM9!

No Values Returned

 

?!

Returns the SDI-12 Address

 

aI!

CampbellSci, Operating System Version,
Product Serial Number

 

Campbell Scientific recommends using separate terminals when possible. However, multiple CS650 sensors can connect to the same data logger control or U terminal. Each must have a unique SDI‑12 address. Valid addresses are 0 through 9, A through Z, and a through z. The CS650 ships with a default SDI‑12 address of 0 unless otherwise specified at the time of ordering. Change the SDI-12 address through Device Configuration Utility (see A200 and Device Configuration Utility) or with a terminal emulator in SDI-12 transparent mode (see SDI-12 sensor support).