Campbell Hausfeld COM220 Manual Do Utilizador

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COM220 Telephone Modem 
 
TABLE 1.  Dataloggers that Require Direct 
12 VDC Connection to COM220 
CR10(X) with silver wiring panel 
CR10(X) with black CR10 wiring panel (P/N 
8032) 
21X(L)—serial number 13,442 or lower 
CR500
⎯serial number 1764 or lower 
CR7—700X serial number 2778 or lower 
 
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.   
The modem must be grounded for its transient protection 
to work. 
CAUTION 
3.3  Telephone to MD485 or Telephone to RF Systems 
Telephone to MD485 or telephone to radio configurations can be utilized for 
communicating with multiple dataloggers through one telephone line.  For 
telephone to MD485 or telephone to radio communications (with no datalogger 
router), the COM220 should be set for ME mode.  The COM220 and MD485 
should be set to the same baud rate.  When using a PakBus network with a 
datalogger configured as a router, the COM220 can be set for SDC7 and the 
radio for SDC8, or vice versa.  Contact a Campbell Scientific Applications 
Engineer for more information.  In addition, Appendix A.4.4 includes example 
programs for both a router datalogger and a remoter datalogger communicating 
by telephone to MD485 or telephone to radio.  
3.4  Telephone Service 
The goal of the telephone company is to provide you with the best service it 
can.  In order to do this, it may occasionally be necessary for them to make 
changes in their equipment, operations, or procedures.  If you have any 
questions about your telephone line, such as how many pieces of equipment you 
can connect to it, the telephone company will provide this information upon 
request.  If the telephone company requests information concerning the 
equipment which you have connected to your telephone line, the FCC 
registration number and the ringer equivalence number (REN) of the COM220 
are listed on its label.  Additional technical information from the FCC and IC on 
the COM220 is available in Appendices D and E, respectively.