Nor-Tronix NX-4a User manual
User’s manual NX-4a Side 1
User’s manual
and installation instruction
NX-4a
Personal Safety System for
mobile homes
Alarm for gas, smoke and motion*
* (Motion detectors optional)
Rev. 11 eng.
User’s manual NX-4a Side 2
Introduction
Thank you for purchasing a NX-4 gas/smoke security system. Since your and others safety may relay
on proper function of this product, we ask you to carefully read this manual so you can fully
understand how to use it, how it works and how to install it. It is not very complicated.
Table of contents:
What is NX-4 intended for?........................................................................................................2
What functions does NX-4 have? ...............................................................................................3
What gases does the NX-4 detect? .............................................................................................3
How to use the NX-4..................................................................................................................4
How to test the NX-4..................................................................................................................4
False alarms ................................................................................................................................5
Installation ..................................................................................................................................5
Connections ................................................................................................................................6
Wiring external motion detectors ...............................................................................................7
Adjusting the sensitivity for the motion detectors ......................................................................7
Wiring external outside lights/spotlights ....................................................................................8
Wiring external lamps with extra relay.......................................................................................8
Wiring an additional alarm sounder............................................................................................9
Wiring external outputs with relay .............................................................................................9
Maintenance................................................................................................................................9
Technical specifications............................................................................................................10
Overview over all the connection points: .................................................................................10
Warranty ...................................................................................................................................11
Service: .....................................................................................................................................11
Your notes:................................................................................................................................11
What is NX-4 intended for?
NX-4 is a personal safety alarm system primarily intended for use in mobile homes where health and
life can be endangered if you are attacked with narcosis gas by robbers, gas leakage from cooking
apparatus, fire or unknown persons (which may be robbers) close to the vehicle*. All the built in
functions in the NX-4 will provide an added insurance against these hazards. You might look at NX-4
as an “electronic night watch”.
NX-4 operates at 12 or 24V and is well suited for mobile homes, trucks and caravans.
*Motion detectors are optional.
User’s manual NX-4a Side 3
What functions does NX-4 have?
1. Warning of ”narcosis” gases.
Alarms many gases with anesthetic effect on humans. These gases are often highly explosive, have a
strong smell and spreads evenly in the room. The NX-4 will sound the alarm long before these gases
reaches dangerous concentrations. If outside lamps are connected to NX-4, they will flash when the
“Narcosis” gas alarm is trigged. This will help to attract attention from others near by.
2. Warning of propane/butane gas.
This sensor is separate from the main unit and installed by the floor in order to detect the heavy
propane gas as early as possible. This sensor is also very sensitive for hydrogen from over charged
batteries.
3. Warning of fire.
The smoke detector does not only detect smoke and fire, but also other air pollutions like exhaust gas
and generally poor air quality. It also detects many odorless gases used by robbers witch makes
humans sleep heavily. This is very dangerous because such gases may displace the oxygen and
suffocate humans. You may experience alarms from this detector if the air quality becomes poor in
general. This is in many cases an indication of insufficient ventilation.
4. Warning of persons nearby.
NX-4 is equipped with inputs for outside mounted infra read motion detectors. The detectors will
alarm the presence of persons close to the vehicle. Occasional by passers will be detected and the
lamp(s) will light (if equipped), but no alarm will sound. However, if motion persists in the alarm zone
for certain amount of time, the alarm will sound. The indoor alarm volume may be adjusted to a
desired level or completely off. This is convenient if you are parking at a “safe place” where people
normally are passing all the time.
An added benefit from the motion detectors and lights is that you will get an automatically operated
welcome/work light for your self when you are leaving or arriving to your vehicle at night. Burglars
also tend to dislike working in a lighted area, especially if the light comes on when they arrive.
One detector on each side will give adequate protection in most cases.
Special made motion detectors are recommended because they are made to withstand the environment
and have the correct electrical data.
Connection of external equipment.
NX-4 has several external alarm outputs for connection of equipment like extra alarm sounder,
forwarding of alarm signals to a cellular phone alarm sender, external flood lights, propane gas shut
down valve and so on.
What gases does the NX-4 detect?
NX-4 has three different gas detectors. Each detector has a specific target gas, but they all will also
overlap each other to a certain extent. That means that the low mounted propane sensor also will d
etect
other heavy gases. The table shows the various gases the sensors will detect. The first gases are the
target gas, the lowest in the table will be detected, but with less sensitivity.
”Narcosis” detector: Smoke detector: Propane detector (external):
Acetone Hydrogen Iso butane
Ethanol Ethanol Propane
Benzene Carbon-monoxide Ethanol
Carbon-monoxide Methane
Iso butane Hydrogen
Methane Carbon-monoxide
User’s manual NX-4a Side 4
How to use the NX-4
NX-4 is normally used at night while sleeping. Flip the power switch to “ON” position and the red
“Heating” lamp will light. After a heating period of 2-2,5 minutes, the green lamp will light and NX-4
is ready. (Motion detectors will work immediately when NX-4 is switched on, but the alarm sounder
will no work until the green lamp is on).
The sensitivity of the three gas detectors must be adjusted before the NX-4 is ready for use. When the
heating period is over and the green lamp is on, turn the sensitivity knob slowly upwards until the
alarm triggers the sounder, then turn the knob approximately 2 scale marks backwards from the trigger
point. Repeat this procedure for all three detectors (Smoke, “Narcosis” and Propane. When this is done
there is rarely necessary to adjust it again other than for checking the alarm and sensitivity level
(should be done on regular basis). Hot weather, high air humidity and many people in the room may
require lower sensitivity settings.
Note: If the NX-4 has been out of use for a period of time or when it is powered for the first time, let it
be powered for a day or two and then readjust the sensitivity.
When many people are present, the air quality will generally be lower and this may cause the smoke
alarm (and sometimes the “Narcosis” alarm) to trigger if it first was adjusted in an environment with
fewer persons.
Too high sensitivity setting will cause the alarm to trigger unwanted. Too low sensitivity setting will
not totally disable the alarm, but a higher density of gas is required to trigger the alarm.
Every gas detectors have their own areas where they are the most sensitive (See the chapter about
“which gases does NX-4 detect”. Each detector has a separate indicator lamp in order to distinguish
the detector that sounds the alarm.
If outside mounted motion detectors are connected:
The motion detectors have two stages. The first is immediate and is triggered by the first sign of
motion and lights the outside lamps if installed. No alarm will sound at this stage. The next stage is
delayed and gives an audible inside alarm after a certain amount of time. The delay time is adjustable
with the Motion detector sensitivity adjustment knob inside the NX-4 (see the chapter “Adjusting the
sensitivity for the Motion Detectors”). The time delay is adjustable from approximately 6 to 30
seconds. Normal position is in the middle. If more than two motion detectors are connected, a lower
sensitivity setting is recommended.
If you are in an area where people normally are visiting and passing by, you do not want the alarm to
sound. Therefore the alarm volume is adjustable from full to no alarm at all. Set the alarm volume to
something in between if you want just a discrete notification that people are outside.
If outside lights are connected, the NX-4 may be left ON in order to provide the owners a “Welcome
light” when coming home at night. Also the automatically activated light will make burglars
uncomfortable and may prevent theft.
How to test the NX-4
The simplest test is just to turn the sensitivity adjustment knobs upwards (Clockwise) just until the
alarm sounds, then approximately two scale marks back. Do this test at regular basis. When doing this
test note if the trigger point is approximately two scale marks up from where the alarm sounds. (Two
scale marks is just a guideline. You may want less sensitivity, but rarely more). This way you will be
familiar with the environment influence on the alarm and you will not encounter false alarms.
A more thorough test is done with actual gas. The “Smoke” and narcosis detectors are located in the
NX-4 main unit. Open a bottle of alcohol, hold it 10-20cm from the unit and blow above the bottle
neck and against the unit. After a short while the alarm will sound and both “Smoke” and Narcosis gas
detectors shall react. The propane detector is tested by holding a gas lighter directly against the
opening of the detector aluminum housing and release a very short dose of gas without lighting flame.
The Propane detector shall react immediately.
Do this test at least once a year and always immediately after installation.
User’s manual NX-4a Side 5
False alarms
The “Narcosis” gas detector is sensitive to alcohol. It is normal that it will react if alcohol is handled
near the NX-4. If you are breathing on the NX-4 after consuming alcohol, it shall react.
NX-4 will normally react on the propellant gas in most spray boxes.
Smokers may experience alarms even if they are not smoking at the moment. This is because the air
quality is generally lower than normal and a small added pollution could be enough to trigger the
alarm. If so, a lower sensitivity setting or added ventilation may be required.
The smoke detector is very sensible to car exhaust so if NX-4 is ON while driving in tunnels or close
behind other cars, it may react. However, this should not be a problem because NX-4 is to be shut off
while driving. It does not harm anything to have it ON, but it has no purpose and if outside lights are
connected, it will come on all the time.
The motion detectors will react on anything hotter than the background as long as it moves. That
includes pets, sunlight behind a branch moving in the wind, warm gusts and humans. This will cause
the light to come on (if equipped), but no alarm will sound at this point. If the motion in the detection
zone persists for a certain amount of time, the alarm will sound. This will filter out most false
detections, but if false alarms occur, you can reduce the sensitivity. More detectors create more (false)
detections and requires lower sensitivity). False detections lights the outside light, but that should not
bother anyone because nobody will know. (See the chapter “Adjusting the sensitivity for the motion
detectors”).
Installation
Install NX-4 main unit approximately 1,5-2m above the floor in a free and open place in the living
area where it is easy to reach. Do not install it inside a sleeping place or inside lockers. Be aware that
NX-4 will detect alcohol fumes from opened bottles with drinks containing alcohol. Avoid placing
NX-4 close to bar lockers if possible.
NX-4 will react on “spent air” human breath with alcohol, human “exhaust” so if the ventilation is
poor, this may create “false “ alarms. This is why NX-4 should not be installed to close to bed sites. If
possible it is convenient to install it on the wall close to the electric distribution center or at the side of
a locker going from floor to roof. Then it is convenient to route the wire for the propane detector (and
the other wires) inside the locker .
Remove the four screws retaining the front of the unit.
Attach it to the wall with two screws trough the holes
shown. Drill holes for wires in the wall where the larger
holes in the unit bottom is located. If the wires shall not
go trough the wall, drill holes in the side of the NX-4
cabinet for wires. When all wires are connected, reinstall
the front. Be careful not to bend the red indicator lamps
in the process.
Install the propane sensor approximately 10-15 cm above the floor. The location is not critical. Install
it with a screw through the smallest hole in the aluminum housing. Route the wire to NX-4 and cut off
the excessive cable.
If external outside lamps are not used, NX-4 can be powered from almost any circuit. There will not
be any particular requirements for the wire gauge or power capacity. The power requirement for NX-4
is only 2,4W.
If Outside lamps are connected, NX-4 must also carry the load for the lamps. The power circuit should
have a 15A fuse and have at least 1# wire gauge. If outside lamps are less powerful, you can replace
the internal lamp fuse FU1 with a smaller one in order to power NX-4 from a circuit with less
capacity. The power circuit capacity must always be grater than the internal lamp fuse FU1! This way
NX-4 will not be disabled by broken fuse if the lamps are short circuited from the outside.
We recommend powering NX-4 from a circuit that is switched off by the main switch for the living
area.
User’s manual NX-4a Side 6
Connections
All connections are referred to connectors J1, J2 and so on. Each J-connector has pins numbered from
1 to 3 as shown. Note the small yellow adjustment wheel for the sensitivity setting of the notion
detectors. The illustration shows the NX-4 internals when the front is removed.
The following table shows all the connections. (Se the chapter “Technical specifications” for more
details and electrical data).
Connector J1 Propane sensor Connector J3 Motion detectors with positive signal
1Red/brown +5V 1+12V out
2Green GND/Ground 2GND / Ground
3White Signal 3Signal input, active high/positive
Connector J2 External outputs Connector J4 Motion detectors with negative signal
1All gas detectors combined 1+5V out
2Propane gas separately 2GND /Ground
3Motion, delayed 3Signal input, active low/negative
4External alarm sounder Connector J6 Power input and lamp output
112/24V Power supply
2GND / Ground
312 / 24 V output to external lamps
Note. The external outputs are not fused and will be destroyed if over loaded.
User’s manual NX-4a Side 7
Basic wiring.
The illustration shows the power supply and propane detector connected to the unit. A 15A
fuse is shown at the power line, but that is only required if outside mounted lamps are being
used. If wrong power supply polarity is applied to NX-4, it will not work, but it will not be damaged
and no fuse will blow.
Wiring external motion detectors
Connector J3 is used
when detectors have
active high/positive
signal. Connector J4 is
for detectors with active
low/negative signal. Se
the chapter ”Technical
specifications” for more
information.
Several detectors can be
connected in parallel as
long as maximum load
capacity is not
exceeded, (provided the
detectors them selves
can be connected in
parallel).
Some may wish to
totally disable the
motion detector
function for a period of time. To do this we recommend installing an external switch at the power wire
to the motion detectors.
Adjusting the sensitivity for the motion detectors
This is an operation done by the installer and does normally not require any further adjustment unless
you are experiencing false alarms or wish another sensitivity level.
The little yellow adjustment knob is located under the front panel. The knob has a small arrow
showing the set position. Turn the knob with your fingers, no tools is required. (Take care and do not
bend the indicator lamps or harm any of the internals in the NX-4). Maximum sensitivity is when the
knob is turned fully clockwise, and the opposite. See the detector manual for correct setting.
User’s manual NX-4a Side 8
If more than one detector is installed, lower sensitivity setting is recommended. Do your own test of
the sensitivity by walking into the detection area and see if the alarm reacts normally. The alarm
should sound after about 30 seconds of motion in the detection zone (Standing still will not be
detected). Do not set it too sensitive because it will also detect pets, sunlight, warm winds and so on,
so the delay time set by the sensitivity knob is required to filter out those false alarms. To high
sensitivity will let false signals through.
Wiring external outside lights/spotlights
You can use the maybe already existing
outside lamp by connecting a wire directly
from NX-4 to the outside lamp without any
fuse or switch. The light will then be lighted
automatically by NX-4 (when powered) and
manually with the existing light switch.
You can also connect this output to the hazard
lights or marking lights if desired. We do not
recommend connecting any alarm horn to this
output because of the nature of Infrared
detectors and possibility for false alarms.
If external spotlights are installed, 20-55W is
recommended (max 110W without extra
relay). Remember that the power circuit to
NX-4 must be able to carry the load from the
lamps. The power circuit should have 15A
spare capacity. If less powerful lamps are
being used, the power circuit to NX-4 can be
smaller, but if so, replace the internal fuse FU1 with a smaller one.
Wiring external lamps with extra relay
If more outside lamps
than NX-4 can drive
directly are desired, an
extra relay can be used to
increase the load capacity.
Also if extra relay is used,
the NX-4 itself does not
have to carry the load
from the lamps and can be
powered with thinner
wires and from a less
powerful circuit. This
may simplify installation
especially if lamps are
installed later and NX-4
already is powered from a circuit without capacity to carry the load of outside lamps.
User’s manual NX-4a Side 9
Wiring an additional alarm sounder
An additional alarm sounder may
be required if NX-4 is far away
from the bed or if the residents
have reduced hearing.
Any 12V type buzzer/sounder can
be connected as shown. The max
capacity of this output is
approximately 10-15mA. Use 12V
sounders also in 24V systems. A
sounder connected to this output
will also be adjusted in volume
together with the internal sounder.
(Connector J3 pin 1 is a 12V
power output that can be used for
both 12V motion detectors and the alarm sounder).
Wiring external outputs with relay
This is an example of how to wire the external outputs to heavy loads that not can be connected
directly to NX-4´s outputs. The wiring will be the same for all outputs at J2 pin1, 2 and 3. It is also
possible to combine these outputs by connecting them together.
The example shows an external alarm horn connected to the “Gas combined” output. A similar circuit
can be used for a shutting valve at the propane bottle controlled by the “propane” output.
Note: These outputs are not fused and will be destroyed if over loaded.
Maintenance
No particularly maintenance is required, but regularly readjusting of the gas detector sensitivity is
recommended. This will ensure proper function and avoid false alarms.
Do a full function test once a year as described in the chapter “How to test NX-4”.
If NX-4 is used constantly, we recommend sending the unit for service and possible sensor
replacement after approximately 6-7 years.
If NX-4 has been exposed to high air humidity or left OFF for a longer period of time, it may be
required to leave it ON for a day or two in order to attain normal sensitivity.
If outside motion detectors are used, they have to be cleaned on regular basis. Clean with a cloth and
mild soap water. Avoid flushing directly at the detectors.
User’s manual NX-4a Side 10
Technical specifications.
* Power consumption with propane detector connected, but without any external components.
To visualize the size of the power consumption, NX-4 will empty a 12V 70 Ah battery in 6 weeks if
used only at night.
Overview over all the connection points:
Connector J1 Propane sensor Connector J3 Motion detectors with positive signal
1Red/brown +5V 1+12V out
2Green GND/Ground 2GND / Ground
3White Signal 3Signal input, active high/positive
Connector J2 External outputs Connector J4 Motion detectors with negative signal
1All gas detectors combined 1+5V out
2Propane gas separately 2GND /Ground
3Motion, delayed 3Signal input, active low/negative
4External alarm sounder Connector J6 Power input and lamp output
112/24V Power supply
2GND / Ground
312 / 24 V output to external lamps
Operating voltage: 11-30V DC
*Power requirements: 2,4W (ca. 200mA at 12V and 100mA at 24V)
Relay output for external lamps J6 pin 3 Max 10A load
Operating temperature: 10-30 °C
External alarm outputs
Combined output for all
gas detectors
J2 pin 1 Active low. Max load approx. 0,4A each. 10k ”pull up”
resistor. Low level <=1V.
Separate output for the
propane detector
J2 pin 2 Active low. Max load approx. 0,4A each. 10k ”pull up”
resistor. Low level <=1V.
Output for delayed motion J2 pin 3 Active low. Max load approx. 0,4A each. 10k ”pull up”
resistor. Low level <=1V.
Output for extra alarm
sounder
J2 pin 4 12V approx. 10-15mA max load. Volume adjustable.
Active low analog output.
Motion detector connections:
12V output in 12V systems J3 pin 1 10-12V, max approx. 200mA load
12V output in 24V systems J3 pin 1 12V, max approx. 50mA load
5V output in
12/24Vsystems
J4 pin 1 5V, max approx. 50mA load. Current limited by a 10
ohm resistor in series.
Signal input positive J3 pin 3 3,5-30V positive signal. Approx. 20k input. imp.
Signal input negative, J4 pin 3 Active below 1,5V. Approx. 20k input. imp.
Delay time at stage 2 for the motion
detector alarm
Approx. 6-30 sec. provided the signal is constant from
detectors. Adjustable with internal potentiometer.
Dimensions (L, W, H) 143x82x38mm
Weight: 210g
User’s manual NX-4a Side 11
CE Approval
NX-4 meets the requirements in the following standards:
Immunity: EN 50082-2
Emission: EN 50081-1
Warranty
1 year from the date of purchase. The warranty will cower any fabrication faults. The warranty will not
cover faults caused by improper use, incorrect connections or normal wear.
Service:
If service or repair is required, contact your dealer for information.
If necessary, contact the manufacturer: (Remember to provide en exact description of the problem).
Also look at the manufacturers web site for information and possible manual updates.
Nor-Tronix
Huitfeldtsgate 24
3263 Larvik
Norway
Tlf: +47 33 14 10 40
Fax: +47 33 18 34 66
E-mail: post@nor-tronix.no
Web side: www.nor-tronix.no
Your notes:
User’s manual NX-4a Side 12
Dealer:
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