Campbell Scientific ET107 Evapotranspiration Monitoring Station - Manual (Page 47)

ET107 Weather Station
2.5.2.2 External Installation
The following modem kit components are used to make the external
connections:
(1) Direct Burial Splice Kit
(1) 20 ft Telephone Patch Cord with Connector
1) Connect the 20 foot patch cord to connector marked COM on the external
back panel, under the protective cover.
It’s very important that each plug is completely seated on to the
connector and the locking ring turned 1/4 revolution clockwise.
Failure to seat the plug completely could cause corrosion and
water damage to both the enclosure and the sensor cable.
2) Splice the labeled “Tip” and “Ring” lines of the patch cord to the
telephone service line. Use the direct burial splice kit when splices are in a
valve box or buried.
The splice and wire nut must be completely immersed into the
silicon gel inside the splice tube to be waterproof.
2.5.3 Short-Haul Modem
Short-haul modems enable communication between a datalogger and computer
over two twisted pairs of wires. The maximum distance between modems is
determined by baud rate and wire gauge. At 9600 baud, the approximate
maximum cable length is 6.0 miles using 19 AWG cable. DCE / DTE switches
on the modems are set to DCE.
It's critical to use at least a two twisted-pair cable with a shield
wire. Shield wire(s) and/or any additional unused conductors must
connect to an earth ground at one end or the other of the cable run.
NOTE
NOTE
NOTE
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