User Manual

Modbus/SDI-12 Gateway User Manual Page 5 of 12
Last Updated: August 20, 2013
Modbus Settings
Along the left side of the Configuration tab, you have the following options:
 MB Address – This is the Modbus address to which the unit will respond when installed
in the field, after configuration.
 Baud Rate – This is the baud rate to be used for the final field installation.
 SDI-12 Power Control – This selects when power is applied to the +14V SDI Power
terminal. Use Always Off if the devices have another power source, Always On to
provide power continuously, or On When Polling to power the terminal only when
polling sensors.
 Poll Interval – If SDI-12 Power Control is set to On When Polling, this sets the number
of seconds between consecutive attempts to poll all sensors.
 Power up Delay – If SDI-12 Power Control is set to On When Polling; this sets the delay
in milliseconds between application of power and the first attempt to poll a sensor.
Sensor Commands
Use the following options to manipulate the list of sensor commands:
 Add New Command to List – Click this button to add a command.
 Remove Selected Command – Click to remove the currently highlighted command from
the list.
 /\ and \/ buttons – Click to move the currently highlighted command up or down in the
list.
When you have added one or more commands to the list, click on a command to
highlight it and then set the options for that command below the list in the Command Detail
panel:
 Address – Enter the one character SDI-12 address of the sensor, typically 0-9 or a-z or
A-Z
 Command Drop-down Box (default of Measurement) – Select the SDI-12 command to
use.
 CRC check-box – Most commands allow optional use of CRC validation. (CRC
validation is requested by default)
 Poll Interval – If the SDI-12 Power Control is not set to On When Polling, this sets each
command's desired polling interval in seconds.
 First Value – For commands that may return multiple values, enter the sequence of the
first value to be saved.
 # Of Values – For commands that may return multiple values, enter the number of values
to be saved. For example, if First Value is 4, and # of values is 2, then the 4
th
and 5
th
values returned from this sensor command will be saved, and any others will be ignored.