Cirronet HopNet 10 Series, Руководство пользователя

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HN-3010 Base/Remote
800281 Rev. B HopNet Family of Products 33
Cable Interface
When you install the cable, check the cable interface for the two power connections
VCC and GND to ensure that the supply voltage into the remote never drops below
7.5 V. During initial turn-on, the remote can draw up to 700 mA. This surge current
will produce a sizable voltage drop across the combined resistance of the VCC
and
GND wires in the cable assembly. If the resulting supply voltage into the Remote
drops below the 5.5 V limit, the microprocessor in the Remote will fail to reset and
the unit will not turn on. The HN-3010 will consistently turn on as long as the
combined resistance of the VCC
and
GND wires in the cable assembly is less than 10
ohms and the supply voltage (at the host end of the cable) is a minimum of 7.5 V.
The voltage drop across the wiring should not be a problem once the unit has
successfully turned on because the maximum operating current of the Remote is
much lower during standard operation than it is during the initial surge.
Aiming the Antenna and Placing the Remote
Use the following guidelines for aiming the antenna and placing the Remote.
•
Do not place anything immediately in front of the antenna that could obstruct its
radiation pattern. Because the antenna in the HopNet Remote is inside the unit,
the antenna must have a clear line of sight.
•
Use the sticker on the Remote unit to help you locate and aim the antenna. The
sticker indicates which direction the antenna is pointing.
•
Be sure the antenna end of the Remote faces the Base or Repeater that it is
communicating with. Our tests have found that antenna placement is not critical
as long as the patch antenna is facing in the general direction of the other end of
the link.
•
If possible, place the Remote unit at a higher elevation than the structures
surrounding it to increase range and link reliability. Since the Remote will operate
with up to 90 meters of cable between it and the Host when configured as an RS-
485 device, you can mount the unit on top of a building or other structure that will
provide higher elevation.