Specifications

COM220 Telephone Modem
CAMPBELL
SCIENTIFIC
INC.
CR10
MADE IN USA
WIRING PANEL NO.
EARTH
DIFF
SE
AG H L AG H L AG H L AG GGE3 AG
4 5 6
78 910 1112
GGGG
12V 12V
SWITCHED
12V
G12V
POWER
IN
SERIAL I/O
SE
DIFF
AG H L AG H L AG H L AG GGE1 E2
1 2 3
12 34 56
G 5V5VP1 P2 C8 C7C6C5C4C3C2 C1
CONTROL
12V
SWITCHED
To Earth
Ground
14 AWG Ground Wire
SC12 Cable
Telephone Wall
Jack
Red
Black
(Ground)
(+12v)
FIGURE 4. CR10X with CR10 Wiring Panel and COM220 Using RJ11C Telephone Jack
3.2 Connecting to Earth Ground
Connect the green 14 awg grounding wire (provided with the COM220) to the
ground terminal (GND) on the COM220 and to the enclosure’s earth ground
connection. If the site does not have a grounded enclosure, then connect the
ground wire directly to an earth ground connection. The datalogger ground
should also be tied to the earth ground (see Figures 3 and 4).
The modem must be grounded for its transient protection
to work.
CAUTION
5