Campbell Hausfeld SDM-CD16AC Manual Do Utilizador

Cables connecting the terminals of the datalogger and 
SDM device should be kept as short as possible to 
minimize the risk of corruption of the signals and damage 
from induced surges.  Where long cable runs (>3 m) are 
unavoidable and the cables run outside, some extra 
protection may be required for the SDM control terminals.  
Please contact Campbell Scientific for further advice.  
When connecting wires to the SDM signal terminals please 
ensure they are at ground potential before making the 
connection, e.g. by touching them to the earth terminal. 

For datalogger connections, see Table 1. 

Multiple SDM-CD16AC's may be wired in parallel by connecting the 
datalogger side of one SDM-CD16AC to the next.  For CR10 and 21X 
dataloggers, the total length of the cables connecting the SDM-CD16AC's 
should not exceed 20 feet. 

Total cable lengths in excess of 20 feet will adversely influence 
communication performance.  For CR7 dataloggers, the total cable length 
should not exceed 600 feet. 

Refer to Figure 3 and Table 1 for SDM-CD16AC operating power and control 
connections to the datalogger. 

Figure 2 shows how the switches in each channel operate.  NO means 
“normally open”, NC means “normally closed”.  COM means “common” to 
NO and NC. 

In most applications, the SDM-CD16AC acts as a switch (controllable break) 
in one wire of the circuit powering the controlled device.  One side of this 
break may have power (hot).  Figure 4 shows an example.