Campbell Scientific COM310 Voice Communications Modem - Manual (Page 30)

COM310 Voice Communications Modem
6.3 Grounding the COM310 System
Connect the green 14 AWG grounding wire (provided with the COM310) to
the GND terminal on the COM310 and to the station enclosure’s earth ground
connection. It is important that you connect the COM310 and datalogger
directly to a high quality earth ground. Read the datalogger manual section on
GROUNDING for details on creating such an earth ground.
A quality EARTH GROUND connection to the COM310
and datalogger maximizes protection against electro-
static discharge! Follow carefully the EARTH
GROUND scheme in Figure 4. The COM310 employs
spark gaps on the phone lines; however, they will be
ineffective without quality earth grounding. WARNING
FIGURE 4. COM310 Grounding and Alternate 12VDC Power
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