Campbell Scientific SDM-AO4 4-Channel Continuous Analog Output Module - Manual (Page 6)

SDM-AO4 Four Channel Analog Output
4. Physical Connections
Figure 1 shows the front panel of the SDM-AO4. The terminal block on the
left is used for connection to the datalogger and the terminal block on the right
provides the continuous analog output. The two ground ports on the left block
are identical and at the same potential.
Table 1 describes the terminal block connections. Multiple SDM-AO4s may
be used by connecting the datalogger side of one SDM-AO4 to the next.
Campbell Scientific does not recommend connecting more than six SDM-
AO4s to one datalogger.
The CABLE5CBL-L or similar cable is used to connect the module to the
datalogger. A 1-ft cable length should be sufficient when both datalogger and
module are housed within an ENC12/14 enclosure; a 2-ft length may be
required if the datalogger and SDM-AO4 are housed at opposite ends of an
ENC16/18 enclosure.
CRBasic dataloggers should use the SDMSpeed instruction if the cable length
is longer than 20 feet (see Section 6.1.2). The maximum recommended cable
length for the CR7 is 600 ft. For other Edlog dataloggers, the maximum
recommended cable length is 20 feet.
Cables connecting the terminals of the datalogger and
SDM device should be as short as possible to minimize the
risk of corruption of the signal and damage from induced
surges. CAUTION
With power supplied to an SDM-AO4 and before execution of the datalogger
program, a random voltage between ±5 Volts will be output. To avoid
outputting erroneous voltages to the receiving device, connect the SDM-AO4
to the datalogger, start the program, and then connect the receiving device.
The order of connections is critical. ALWAYS CONNECT
GROUND FIRST, followed by 12V and then the Control
Ports. CAUTION
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