Nautel NX3, Руководство по установке

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NX5/NX3 INSTALLATION MANUAL CONNECTING AC POWER
PAGE 2.4.2 VERSION 3.1 2021-04-22
5. For bottom entry only: lower the position of the ferrite assembly on the interior right-hand wall of
the NX5/NX3 by loosening two nuts, moving the ferrite assembly down to the lower set of
mounting studs and re-tightening the nuts (see
Figure 2.4.1 on page 2.4.3 ).
NOTE:
The ferrite assembly is designed to accommodate two different positions: upper (for top
entry) and lower (for bottom entry). This allows optimum wire routing to the power transformer’s
primary terminals. Nautel factory configures the ferrite assembly in the upper position for top ac
entry.
6. Route all cables, as a group, along the interior wall of the NX5/NX3 to the ferrite assembly’s
toroids. For top entry, an internal cable duct is provided to guide the cables from the top of the
transmitter to the ferrite assembly.
NOTE:
If the ac cable is a multi-conductor configuration, you may need to strip back the cable’s
outer jacket (Nautel recommends 90 inches for top entry, 40 inches for bottom entry) to allow
wiring to pass through the transmitter’s ac entrance (top or bottom). The cable channel between
the top of the transmitter and the toroid assembly is approximately 52 inches long.
7. Pass all cables, as a group, down (or up, as applicable) through the ferrite toroids.
8. Verify that the station reference ground is connected to the safety ground stud assembly at the
back of the cabinet.
9. Connect the ac line input to the Line 1, Line 2 and Line 3 terminals on the power transformer (see
the appropriate
Figure 2.4.2 on page 2.4.4 or Figure 2.4.3 on page 2.4.4 for your transformer).
Secure using lugs and hardware provided in the ancillary kit (see Figure 2.4.4 on page 2.4.5 ) or
provide your own lugs that are compatible with up to a 5/16-inch or M8 bolt. If using Nautel
supplied parts, torque lugs to 77 in-lbs (8.6 N-m) and torque M6 bolts to 60 in-lbs (6.7 N-m).
10. Connect the ac ground to the transmitter’s ac ground stud (see Figure 2.4.5 on page 2.4.6 ), again
using a lug provided in the ancillary kit. If using Nautel supplied parts, torque lugs to 77 in-lbs
(8.6 N-m) and torque the nut on the ground stud to 67 in-lbs (7.5 N-m).
11. Based on your nominal line-to-line voltage, select the appropriate tap position on the power
transformer. All three phases must be set to the same tap (see the appropriate Figure 2.4.2 on page
2.4.4 or Figure 2.4.3 on page 2.4.4 for your transformer and Table 2.4.4 on page 2.4.5 ). If necessary,
use the hardware already on each of the three copper straps to connect the straps to the new tap
positions. Be sure to scrape any excess epoxy off the electrical joint area.
NOTE:
During the Commissioning procedure (see “Commissioning Tasks” on page 2.8.1 ), you will
be required to check an ac sample voltage to confirm the tap settings are correct. It may be
necessary to adjust the tap settings at this point, which may involve using the ±5 V or ±10 V
minor taps.