Nautel NX5 AM, Preinstallation Manual

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NX5 PRE-INSTALLATION MANUAL ELECTRICAL REQUIREMENTS
VERSION 0.1 2015-08-01 PAGE 1.5.7
Ac Disconnect Switch
Install an external ac disconnect switch between the ac power source and the transmitter. For safety,
place the ac disconnect switch close to the transmitter and label it
TRANSMITTER EMERGENCY ON/
OFF SWITCH
.
Ac Transient Power Protection
Protect all conductors from the ac power source by connecting bi-directional surge protection devices
between each conductor and the station reference ground.
A surge protector panel containing suitably rated varistors is available from Nautel. Install the surge
protector panel close to the station reference ground, and as close as possible to the ac service
entrance.
The ac power source usually has the lowest impedance path to ground during a lightning strike and
normally carries most of the lightning-induced current away from the transmitter site. When lightning
hits the power source (for example, striking a transmission line near the transmitter site), a significant
induced current may flow towards the transmitter. The goal of lightning protection is to route the
current around the transmitter to the best available ground.
For detailed information about surge protectors and lightning protection, refer to Nautel’s
Recommendations for Transmitter Site Preparation Manual.