Initial Inspection; Overview - Campbell SDM-SI01A Product Manual

CAUTION: The power ground connection to the data logger should be made with large
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gauge wire, (for example, 16 AWG or 1.5 mm
allowing full protection from static and electrical transients.
CAUTION: The SDM-SIO1A is considered to be a component of a measurement system
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that is installed in an enclosure and wired in accordance with this manual. Due to space
considerations, full details of the maximum ratings of the connections are not given on the
device. Instead the user should study this manual, and in particular
(p. 6), to determine the maximum voltages that are applicable to any terminal before
starting an installation.

3. Initial inspection

Upon receipt of the SDM-SIO1A, inspect the packaging and contents for damage. File damage
claims with the shipping company. Contact Campbell Scientific to facilitate repair or replacement.

4. Overview

The SDM-SIO1A expands the number of serial ports on a Campbell Scientific data logger. It can
be used as a means of collecting data from digital sensors and/or to send commands to sensors
and devices. It can also be used to send data to remote display devices.
The SDM-SIO1A will accept serial data and store it in its buffer allowing remote equipment to
transmit large amounts of data without needing to stop other processes in the data logger whilst
the data is received.
The SDM-SIO1A connects to the data logger via three digital lines using a proprietary protocol
called SDM. It connects to the remote serial device using a standard serial interface that can be
set to RS-232, RS-485, or RS-422 signal levels.
Up to 15 SDM-SIO1As can be connected to a single data logger via the SDM port, allowing the
user to connect 15 different items of equipment to their data logger with ease, in addition to any
connections made to the data logger built-in serial ports. Up to four SDM-SIO4As can be
connected to the data logger as each module uses four successive SDM addresses, one per serial
port.
The SDM-SIO1A can also be used in "talk-through" mode to allow a user to talk, via a terminal
program, to a sensor connected to the SDM-SIO1A for test and diagnostic purposes. Please refer
to the data logger manual for further details.
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) to provide a low impedance path to ground
SDM-SIO1A and SDM-SIO4A Serial Input/Output Modules
Voltage specifications
3