NEC Neax 2400 Ipx Wireless System Manual

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INSTALLATION DESIGN
3. Radio Wave Propagation
Although radio waves used by the Built-in PCS System employ a digital signal of service frequency of
approximately 1.9 GHz band, types of radio waves and types of propagation involved with basic radio wave
propagation are considered to be the same as other analog radio waves.
 Types of radio waves
a. Direct waves: Radio waves that are propagated 
directly and linearly.
b. Reflected waves/
diffracted waves 
(indirect waves):Radio waves that are propagated 
by being reflected or diffracted 
from an obstacle, such as a wall 
and ceiling.
c. Transmitted waves: Radio waves that travel through a 
wall, floor, partition, etc.
d. Propagating corridor 
waves:Radio waves that travel along a 
corridor. (One type of reflected 
waves.)
e. Re-entering building 
waves:Radio waves that go out of a 
building through a window, etc. 
and enter the building again.
FLOOR
CEILING
CEILING
WALL
WALL
WALL
CORRIDOR
ANOTHER BUILDING
WINDOW, ETC. 
						

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 Types of propagation
There are two major types of radio wave propagation: the line-of-sight propagation and the propagation
beyond the horizon. As opposed to a cellular phone, consideration must be given to the line-of-sight
propagation characteristics, where a ZT can be seen directly; as well as the propagation beyond the horizon,
where radio waves travel through walls, ceilings, partition on the same floor, or another floor for a wireless
system used on private premises with a very small service area.
Line-of-sight propagation 
a. Free space propagation:  When a distance doubles, 
propagation loss increases by 
6 dB.
 When a wavelength is halved, 
propagation loss increases by 
6 dB.
Plane earth propagation: When a distance doubles, 
propagation loss increases by 12 dB. 
(It is wavelength-independent.)
b. Propagation beyond the horizon
Multiple wave propagation: Propagation where numerous 
reflected and diffracted waves are 
received. (The original mobile 
communications use this type of 
propagation.) 
						

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INSTALLATION DESIGN
4. Installation of the ZT (Zone Transceiver)
Explained below is how to install the ZT and precautions to be made when mounting it.
a. The ZT is a communication device that sends a weak signal as radio waves, it should not be installed
near and around equipment or an environment listed below to ensure the speech quality and various
kinds of control operations – care must be taken.
[Indoor Installation]
Do not install around equipment capable of emitting noise (high frequency electric waves) such as
wireless apparatus, television set, radio set, fluorescent lightening, and microwave oven.
[Outdoor Installation]
Avoid places easily affected by radio disturbances from cars, etc. (e.g., near a principal road).
When installing by the sea, protect the ZT from salt using the outdoor mounting box and other
protection if necessary.
Avoid places where there is a possibility to cause malfunction by radio waves.
When installing by the sea, protect the ZT from salt using the outdoor mounting box and other
protection if necessary.
Besides, abnormal places with a fear of an explosion, subjected to malfunction by radio waves or to
a strong electromagnetic field.
b. Avoid installing on a clay wall or plasterboard.
c. Ensure the wall or pillar to be used is strong enough to support the weight of the ZT, so that it does not
shake, and has very little vibration.
d. If a possible installation wall contains reinforcing steel, etc., keep the antenna away from the wall by
slightly tilting it.
e. When raising the antenna of the ZT, make sure that it does not touch the wall, etc. 
						

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INSTALLATION DESIGN
2. INSTALLATION PROCEDURE OF ZONE TRANSCEIVER (ZT)
STEP 1: When mounting a ZT on a wall/ceiling, observe the following instructions.
i Do not mount a ZT on a wall/ceiling which cannot sustain the weight of ZT (e.g. a plaster wall,
plywood wall).
ii Make a sufficient space so that the antenna can be placed at any angle.
iii When mounting a ZT on a wall which contains a reinforcing bar near the mounting location, place
the antenna at an angle with the wall so as to make a space between the antenna and the reinforcing
bar.
Figure 2-6  Examples of Inappropriate Mounting
(i) (ii) (iii)
plaster wall
Reinforcing Bar 
						

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INSTALLATION DESIGN
STEP 2: Post the attached dimension drawing on the mounting location so as to mark the locations of screw 
holes. As shown Figure 2-7, two screw holes are provided as the lower mounting position. Depending 
on the mounting location, select either of the two mounting position.
Figure 2-7  Dimension Drawing for ZT Installation (1/2)
Leave a space [more than 4.3 in (110 (mm)] for the antenna.
4.2 (107)
Screw of the mounting tag
Screw of ZT 
4.9 
(
124.4)
Mounting tag ZT 
1.6
 (40
)
6
.3 
(
160)
5.4 (138)
3.2 (80)
4.0 (100)
inches (mm) 
						

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INSTALLATION DESIGN
STEP 3: Secure the furnished screws to the marked locations. In this instance, for the lower mounting screw hole 
select either of mounting options depending on the mounting location.
Figure 2-8  Dimension Drawing for ZT Installation (2/2)
0.2 (5)
0.5 (12)2.4 (60) 0.08 (2)
0.3 (8)
0.2 (5)
Front
0.9 (22.5)
4.9 (124.4)
2.2   (54) 0.5 (13.5)
0.4 (10)
3.1 (78.75) 0.8 (21)
0.08 (2)
0.3 (8)
inches (mm) 
						

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INSTALLATION DESIGN
STEP 4: Mount the ZT on the wall and slide it so that the heads of screws may fix the ZT tightly.
Figure 2-9  Mounting of the ZT
STEP 5: If power feeding from the PCS is impossible, use the “AC adapter” for local power feeding. The “AC 
adapter” is connected to the ZT as shown below.
Figure 2-10  Local Power Feeding
Use either of two screwsWALL
Screw
Connector cover Rear
Modular jack
DC in jack 
						

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INSTALLATION DESIGN
STEP 6: Turn ON the power to the ZT to confirm the lamp indications are normal. Refer to Table 2-1 and Figure 
2-11.
* One cycle is 2 seconds
Table 2-1  Meaning of LED Indications
LAMP LIGHT STAGE MEANING
POWER LIT Light when the power is supplied
STATUS OFF Line is not open
LIT The flicker cycle 
is 0.1 seconds.ZT does not stand by
LIT The light cycle is 
1.8 seconds.All ZT lines are busy.
LIT The flicker cycle 
is 0.2 seconds  
standard.The number of ZT line used. (The number of flicker indicates the 
number of ZT line used.)
Lamp
Time (0.2s)
Lamp
Time (0.2s)
Lamp
Time (0.2s)
Lamp
Time (0.2s)
Lamp 1 line used.
2 lines used.
3 lines used. (All ZT lines are busy.)Time (0.2s) 
						

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Figure 2-11  LEDs on the Zone Transceiver
POWER STATUS
Power lamp Status lamp 
						

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INSTALLATION DESIGN
STEP 7: The angle of the antenna is variable between 0º and 180º as shown below. In a wall-mount installation, 
normally the antenna is set at an angle of 0º so that the antenna may be vertical with the radio zone.
Note:Since the antenna is easily broken, handle it with care.
Figure 2-12  Adjustment of Antenna
90  90 
90