Campbell COM220, Instruction Manual

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COM220 Telephone Modem
1.2 Computer Requirements
A Hayes-compatible modem is used at the computer site with Campbell
Scientific computer software to call the datalogger attached to the COM220.
The computer’s modem must be configured to the proper settings using a set of
modem-initialization strings in the software program’s pick list.
2. Specifications
Standards: V.92, K56Flex, V.90, V.34, V.32bis, V32,
V23, V22bis, V22, V.21, B212, B103
Registration: FCC US: 3A4M508BSM2-T-W
IC 2377 A-SM2TW
TBR21
Operating voltage:
12 Vdc
Current drain: 100 to 120 μA quiescent; 30 mA active
Communication rate between
datalogger and COM220: 9600, 38400, 57600, 115200 bps (selected
by user)
Operation: Full-duplex over standard, analog phone
lines
Operating temperature: –25 to +50 °C std, –55 to +85 °C optional
Dimensions:
16.5 x 2.5 x 6.6 cm (6.5 x 1.0 x 2.6 in)
Weight: 0.16 kg (0.35 lb)
3. Installation
The COM220 is designed to be used with standard, analog telephone lines. It
will not work with a digital telephone line. Connection to telephone company-
provided coin service (central office implemented systems) is prohibited.
Connection to party-line service is subject to state tariffs.
3.1 Connecting to Datalogger
Connect the cable from the telephone RJ11C jack to the modem as shown in
FIGURE 3-2 . If the telephone company has not installed surge protection in
the telephone line (no RJ11C jack), one must install surge protection (pn 6362
or 4330) and connect both the ring and tip terminal blocks as shown in
FIGURE 3-1 .
Current Campbell Scientific dataloggers provide 12 Vdc to the COM220 from
the CS I/O port via the SC12 cable (FIGURE 3-1 ). Older dataloggers do not
provide 12 Vdc on their CS I/O port. When used with the older dataloggers
listed in TABLE 3-1 , 12 Vdc and ground need to be connected via the green
power connector on the side of the COM220 (see FIGURE 3-2 ).
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