Juniper ACX500 Hardware Manual page 120

• Grounding the unit (metal mast or ground cable to the unit's base) is required for the
lightning protection to work properly.
The ACX500 Timing Server can maintain accurate time even if an antenna is mounted in a location that
has limited visibility of GNSS satellites; however, we recommend obstructions should be minimized.
Limitations to satellite visibility for an antenna include overhanging foliage or tall structures. Such
structures can block the GNSS signal from the antenna and cause gaps in the GNSS satellite signal
reception. In locations where satellite visibility is limited, keep in mind the following guidelines:
• Position the antenna on the side of the structure with good visibility toward the equator where more
satellites are visible. For example, if you are in the northern hemisphere, place the unit on the
southern side of the structure unless that view is restricted or blocked. If that view is restricted or
blocked, place the unit on the east or west side of the structure. Avoid the polar side where there are
fewer visible satellites.
• Ensure that the GMT time zone parameter is set while you configure the Timing Server.
• To avoid any potential damage to the GNSS antenna and the router, do not install the antenna in the
proximity of any transmitting RF or high-voltage power sources. This is both a hardware precaution
as well as a personnel safety precaution. Follow all local building code requirements, as well as the
local building electrical codes for power and grounding.
• You must mount the antenna above and away from any electrical systems such as lift mechanisms, air
handlers, HVACs, and other electrical or mechanical machinery.
• The GNSS signals can be reflected by objects such as metal, walls, and shielded glass parts. Do not
install the antenna near good light-reflecting surfaces. Failing to do so might result in distorted GNSS
signals.
• To avoid multipath reflections, do not place the antenna near a wall, window, or other large vertical
objects.
• To prevent damage from lightning, do not place the GNSS antenna at the highest point of the
building.
• You must locate the GNSS antenna at least 3 feet (1 m) away from any metallic objects such as radio
tower, other antenna mast, electrical poles, and so on. See
• Allow at least 6 feet (2 m) of separation between GNSS antennas. See
• The antenna must have an unobstructed 360° view of the sky from 15° above the horizon. See
Figure 31 on page 114.
• Locate the antenna within a reasonable distance of the building cable entry point.
Figure 30 on page 113.
Figure 30 on page
111
113.