KVH Industries IP-MOBILECAST, Руководство по установке

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Before you begin, be sure you understand the
following important requirements:
AC Power Requirements
The Media Server, like the TracPhone antenna
system, is designed to run on 3-wire single-phase
AC power (hot, neutral, and ground). Voltage
between hot-neutral and hot-ground should each
measure between 100-240 VAC.
Many large ships use two-phase, split-phase, or
delta power instead (3 wires: hot, hot, and
ground; no neutral). In this case, voltage between
hot-hot measures the proper voltage (100-240
VAC); while hot-ground measures only half the
voltage (50-120 VAC). Although the Media
Server can operate on this type of power, the
excess voltage present on the second phase will
cause a small amount of current to leak onto
ship's ground. This leakage current might be
unacceptable on some vessels. So check with the
ship's electrician or superintendent and get
permission (with signature on Installation Plan)
before you run the system on two-phase power.
Also ground the chassis, as explained below.
If two-phase power is the only available power
source onboard, and if leakage current is
unacceptable, KVH recommends that you install
a suitable isolation transformer to supply single-
phase power to the Media Server and run a
ground wire from the transformer to ship's
ground. In addition, since ground fault
protection devices cannot detect faults behind a
transformer, you will also need to install a
ground fault monitoring device between the
isolation transformer and the Media Server if
ground fault protection is required on the vessel.
Grounding Requirements
Proper grounding of the Media Server to ship's
ground is critically important, as it protects the
equipment from lightning and electrostatic
discharges (ESD). Failure to ground the chassis of
the Media Server risks damage to the unit and
electric shock.
NOTE: Consider installing an uninterruptible power
supply (UPS) to avoid service interruptions during
power outages and transitions to/from shore power.
Figure 11: AC Power Options
OR
OR
Media Server
Ground
Neutral
N
100-240 VAC
Shipboard
3-Wire
Single-Phase
AC Power
Media Server
Ground
100-240 VAC
Shipboard
Two-Phase,
Split-Phase,
or Delta Power
Leakage Current
100-240 VAC
Media Server
Ground
Neutral
N
100-240 VAC
Single-Phase
Power Input
Ground Fault
Monitor
(when required)
Isolation Transformer
Ground
Ground
50-120 VAC
50-120 VAC
Shipboard
Two-Phase,
Split-Phase,
or Delta Power
Connecting Power
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