Campbell Scientific ET107 Evapotranspiration Monitoring Station - Manual (Page 23)

ET107 Weather Station
2.1.3 AC Power Installation
a) The currently-available AC power option includes a 100 to 240 Vac to
24 Vdc power supply (see note below). The power supply should be
mounted inside a user-supplied junction box according to local electrical
codes. Dangerous electrical accidents may be avoided by locating the
transformer remotely and burying a low voltage line to the station. The
low voltage will carry up to 500 feet on an 18 AWG power cable.
b) Shut off 110 Vac power at the main breaker. Connect the primary leads of
the power supply to the 100 to 240 Vac power source. Connect a two-
conductor cable to the secondary terminals of the power supply. Route the
cable from the power supply to the ET Enclosure according to local
electrical codes.
c) Splice the incoming two-conductor cable to the power cable provided with
the station. Use the direct burial splice kit when splices are in a valve box
or buried.
d) Connect the power plug to the connector marked “Power” on the back of
the enclosure. See FIGURE 2-24.
The AC power supply option for older ET107 stations included a
120 Vac to 16 Vac step-down transformer instead of the 100 to
240 Vac to 24 Vdc power supply. Appendix E, Step-down
Transformer Installation, provides information for installing an
AC power system that includes the step-down transformer.
The splice and wire nut must be completely immersed into
the silicon gel inside the splice tube to be waterproof.
2.2 Tower/Pole
2.2.1 Supplied Components
(1) Upper Tower Section (Tapered)
(1) Lower Tower Section
(6) 5/8 inch Washers
(1) 12 ft 10 AWG Ground Cable
(1) White Tower Cap
(1) 20 ft communications cable (phone or short haul modem)
(1) 20 ft power cable (for AC option only)
2.2.2 Installation
Attach the tower to the base as shown in FIGURE 2-4.
1. Dig a hole close to the concrete base to access the lower conduit opening.
From the hole, trench to the power and communications sources. Remove
the duct tape from both ends of the conduit.
2. Remove the template. Slide the bottom and top half of the pole pieces
together. This is a permanent connection and cannot be taken apart once
they are put together. If a little more force is necessary to put the two
halves together, then get a small block of scrap wood and a hammer. Set
NOTE
CAUTION
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