NV-400, 410, 500, 600
Combustible Gas Detection System
Installation ManualThis manual is for NV-400, 410, 500 and 600.
Thoroughly read this instruction manual before using the equipment so thatit can be used safely and correctly.
Keep this instruction manual where it is readily accessible

New-Cosmos Electric Co., Ltd.

Installation manual No..
GAE-024
Jan. 2006

Table of Contents
1. INTRODUCTION............................................................................................................................... 2
2. SAFE OPERATION .......................................................................................................................... 2
3. UNPACKING........................................................................................................................ ……….3
4. INSTALLATION AND WIRING ....................................................................................................... 4
4-1 How to Install the Indicator and Alarm Unit ........................................................................... 4
4-2 How to Install the Gas Detector ............................................................................................... 6
4-3 Wiring ........................................................................................................................................... 9
4-4 Wiring and Connection............................................................................................................ 12
5. INDICATOR ALARM CIRCUIT DIAGRAM.................................................................................. 17
5-1 100 to 240V AC Input .................................................................................................................. 17
5-2 24V DC Input ................................................................................................................................ 19
6. GLOSSARY..................................................................................................................................... 21

1

1. Introduction
Thank you very much for purchasing NV-400, 410, 500, 600, that is a gas detection /alarm system.
This system is used to prevent leakage of combustible gas. This equipment continuously monitors for leakageof combustible gas, and indicates when a preset level has been exceeded by a lamp and sound. Thoroughly
read this instruction manual before using the equipment so it can be used correctly. Read the instruction
manual of the gas detector as well.
Symbols
The following symbols are used for safety purposes:
DANGER:

Indicates an imminently hazardous situation which, if not avoided, will result in death orserious injury

WARNING:

Indicates a potentially hazardous situation which, if not avoided, could result in death orserious injury

CAUTION:

Indicates a potentially hazardous situation which, if not avoided, may result in minor ormoderate injury. It may also be used to alert against unsafe practices.

MEMO

Operational advice and or instruction.

2. Safe Operation
Carefully read the following so you can use the equipment correctly. Read and understand all applicable laws
and regulations and ensure that you are in complete compliance with the said laws and regulation before
installing or operating the equipment. Qualified persons, following all applicable federal, state, and local healthand safety laws and regulations including OSHA, should carry out installing, wiring, and other works
concerning the equipment.

WARNING

Ground the equipment in order to prevent electric shocks
When wiring and taking the indicator alarm unit and detector head off, be sure to switch off the indicator alarm
unit or stop the power supply in order to avoid electric shocks.
In order to prevent thunderbolts, take lightning protections.
The Indicator and alarm unit is not explosion-proof. Install it in a non-hazardous location.

CAUTION

Do not dissemble, alter the equipment or change its structure and electric circuit. It may affect theperformance of the equipment.
The equipment is not waterproof. Install it in a place where it will not get wet.
Follow all the related laws and regulations when using the equipment.

2

3. Unpacking
The following standard components are packed together with the Gas Detector/alarm. Carefully check thecontents against the list when unpacking. If any components are missing or damaged, contact our dealer /agency.

1

NV-□□□ main bodyGas detector headKD-5 (Diffusion type)PE-2DC(Suction type)
Fuse

Ordered quantity

2 points:2.4 A
4 –12 points: 4 A
L shapedFor Diffusion type gas detector head 2,3,4mm
wrenchFor Suction type gas detector head 2,4,5,8mm
Install place seal(NV-500 only)
Parts to embed the panel (embedded panel only)
Air filter FC-32 with flow checker (for Suction type gas detector head only)
Rainproof cap KW-22(for NV-500 only, for Diffusion type gas detector head only)
Sample gas collector PE-N3 (for Suction type gas detector head only)
NV-□□□ instruction manual
NV-400, 410, 500, 600 installation manual (this book)
Test results of the equipment

1 ea.
2
1 ea.
1 ea.
1
1 set
1 ea.
1 ea.
1 ea.
1
1
1

Optional items (separately sold)
KW-15 for Diffusion type gas detector head KD-5-N
PW-51 for Suction type gas detector head PE-2DC
Rain proof cap
KW-22 for KD-5
Outer alarm
EB-5
Zener barrier for outer BT-150
alarm
Auto drain
AD-40
Rainproof cover

3

Ordered quantity
Ordered quantity
Ordered quantity
Ordered quantity
Ordered quantity
Ordered quantity

4. Installation and Wiring
4-1 How to Install the Indicator and Alarm Unit
The equipment can be hung on the wall or embedded.

WARNING
The indicator and alarm unit is not an explosion-proof construction. Install it in a non-hazardous area.

CAUTION

The indicator and alarm units must be installed in a place where someone is always present and is easy
to read so that taking countermeasures and notifying others in case of an alarm is possible
Do not place the indicator and alarm unit in a place with vibration, electric noise, or corrosive gas.
Avoid places with a high temperature or humidity as well.

(1) How to install on the wall
1) Make holes on the wall as shown in Fig 1.
Installation hole size

Installation

NV-□□□-2A
-2B
-4
-6
-8
-10
-12

hole

Cable inlet

Ｂ
152
230
343
417
491
565
639

Ｃ
100
100
240
240
240
360
360

Fig.1 Dimension for hanging the Equipment on the wall

MEMO

Cable wiring can be done in the back or bottom. To hide the cable, you may
connect it through Backside.

2) After setting the anchors into all the installation holes, put the bolts on upper areas(2 points).Open the main
body panel and grapple the bolts to the upper and lower areas, then screw the 4 bolts tight (upper and lower
areas =4 points)
MEMO

Use an anchor and fix it securely so that the indicator unit will not come off from a wall by any
shock ,such as an earthquake（Recommended bolt size Ｍ６×２０）4

Fig.2 indicator alarm unit installation
MEMO

Maintenance

Leave a 40 cm space underthe equipment’s body for
maintenance work.

Bolt

space

Fig. 2 Embedding on a Panel
Main body(2) How to embed on a panel①Cut out a rectangular opening in the panel as shown in Fig.
bolt(2) How to install Flush mount type panel
1) Cut a panel as shown in Fig 3.
NV-□□□-2A
-2B
-4
-6
-8
-10
-12

Fig.3 Dimensions to Cut a Panel

Ｄ
214
292
415
489
563
637
711

2) Insert the equipment into the opening from front.
Attach the back plate on the back of equipment with the attaching screws and fasten it to the panel with
fixing screws. The equipment can be fixed on a 1.6 to 6 mm thick panel.
Panel

Fixing screw

Equipment

Fixing metal plate

Main body installing screw(2 pcs.)Fig.4 How to install Flush mount type
図４ パネル埋込式の取付方法

5

4-2 How to Install the Gas Detector

CAUTION










The gas detector must be handled with care to avoid damaging the explosion proof construction.
Do not install the Gas detector in locations listed below:-Location where the ambient temperature may drop lower than –３０˚C or exceed ４０˚C.
-Location where dew condensation may occur.
-Location where it could be exposed to direct water.
-Location where corrosive gases may exist.
-Location where get sunshine directly.
-Location where the ambient temperature could change drastically.
-Location where nearby a source of electrical noises.(high frequency, magnetic noises)
Do not install the Gas detector in an atmosphere contaminated with silicon compounds, as silicon could
poison and/or impair the sensitivity of the sensor.
The gas detector should be installed in a location free from vibration.
Avoid severe shocks and /or mechanical impact to the gas detector.
When the gas detector is to be installed in an outside location, make sure to use a rain protective cover orcap.
Use Auto drain (optional item) when use the Suction type detector in a location where the detector could bewatered.
The height of the installation of the detector head is an important factor and related to the gas to be detected,
refer to table below.
Kind of gas
Gases heavier than air ,suchas
LPG
Gases lighter than air, such as
H2, CH4, town gas, natural
gas.

Installation height
Remarks
About 10cm above
For maintenance purpose allow attheleast 7cm space from floor level
floor level
Selectalocation
where
Near the ceiling
maintenance can be easily
conducted.

(1) Diffusion type gas detector
Use Suction type gas detector head in a location where is hard to access for maintenances suchas inside Pit or Duct as well as a location where the gas detector head could be watered.
・Installation
Areas where gases tend to reside
Roof fan

WindowDetector heads

Air intake(Lateral view)(Top view)

Detector head to be installed

Fig.5 Diffusion type gas detector head6

・How to install the fixing plates
Locate the gas detector head between the fixing plates (Saddle and Stand)and tighten the pan-headscrew to fix.
Fixing plate (saddle)
Pan-headFix on the wall with attached the

Fixing plate (stand)

M6 Hexagon Bolt and Nut.

Fig .6 How to install the fixing plates

・How to install the Rainproof cover (optional item) and Rainproof cap(optional item)

Tighten the screw to fix

Rainproof cover（KW-15）

Rainproof cap (KW-22)

Fig.7 KW-15, KW-22 Installation(2) Suction type gas detector head
Suction type gas detector should be used in locations as follows.
1) Inside a piping pit or location where is shut tightly.
2) Furnace sampling3) Location where the ambient temperature is high or low4) Location where is highUse 6Ø×4 Ø pipe work for the Suction type gas detector head and the length should be 30m or less.
And the gas detector head should be installed in a location where is easy to access for maintenance.
7

・Example : locations to install

Drain pit

A location where is not easy to access formaintenances.

Fig.8 Example-location for suction type gas detector head

CAUTION

Sample gas collector should be installed at high location where is free from sucking water.

・Installation for Rainproof cover(PW-51)
Rainproof cover (PW-51)
Gap plate
Sampling tube
Filter with Flow checker(FC-32)

Gas collector(PF-N3)Fig. 9 Example - installation for PW-51

CAUTION

Fix the Rainproof cover tight in case of strong winds such as a typhoon.

8

4-3 Wiring
Use explosion-proof wiring in all potentially hazardous places.
(1) Refer to the following (KD-5, PE-2DC) with regard to wiring for explosion-proof metal conduits.

WARNINGWhen wiring, be sure to turn the indicator and alarm unit off before opening the cover of Gas Detector,
otherwise it may become a source of ignition.

CAUTION










Refer to the explosion-proof guidelines for factory electrical equipment for the wiring connection of theGas Detector.
Do not use cables for wiring in explosion-proof metal conduits.
Select the most suitable material from among rubber, vinyl, polyethylene, etc., for the insulating materialof insulated wiring in accordance with the conditions in the location of use, e.g., the existence of corrosive
substances, the amount of humidity, the ambient temperature, etc.
Route the wiring through rigid steel conduits (JIS C 8305), and provide sealing fittings and compound toseal the pipeline in order to prevent explosive gases or the flames of an explosion from flowing along thepipeline.
Do not use silicon compound because it has an adverse effect on gas sensors.
When flexibility is required, use waterproof flexible fittings with an explosion-proof structure. If rainwater orother moisture enters the Gas Detector, it may cause a loss of function or malfunction.
Provide waterproofing treatment for the joints of wiring ducts and other parts. If rainwater or othermoisture enters the Gas Detector, it may cause a loss of function or malfunction.

NOTE

Cable breaks may occur as secondary damage following disasters such as an earthquake.
This problem can be prevented by providing U-shaped dampers along the cable route.
Example:

When connecting a wiring conduit to a wiring conduit accessory or terminal block, use a JIS B 0202
pipe parallel thread (New Cosmos explosion-proof instruments generally use PF3/4 (G3/4) threads).
Join the parts by using at least five threads of the effective thread portion, then secure the joint tightly
with a lock nut.

9 Mounting Example (KD-5 Diffusion Type Detector)
Partition
Non-hazardous area

Hazardous area
Do not locate any joints of electricalconduits in this space
Flexible

Putty

Union coupling
Diffusion
Gas Detector

Setting fitting
PYRACK

Thick steel metal conduit

Setting fitting
may be placed on
this side.

Coupling

Figure 10
 Mounting Example (PE-2DC Suction Type Detector)
Partition
Non-hazardous area

Hazardous area

Diffusion
Gas Detector

Do not locate any joints of electricalconduits in this space
Flexible
Putty

Setting fitting
PYRACK

Thick steel metal conduit

Setting fitting
may be placed on
this side.

Coupling

Union coupling

Figure 11(2) Cable Installation (KD-5 and PE-2DC)
 Use cables with a rubber or plastic outer covering or with a metal covering suitable to the environment
in the place of installation. The cross section of each cable must be circular and the surface of thesheath must be free of any unevenness. Lay the cable in a protective pipe, such as a metal conduit orcarbon steel pipe, or a metal or concrete duct as needed to protect the cable from external damage.
 Avoid connecting cables together as much as possible. If the direct or branch connection of cables isunavoidable, use a connection box of pressure- and explosion-proof construction and connect thecables inside the box.
 The pressure-proof packing type of lead-in method may be used, provided that the finished outer
diameter of the cable fits the inner diameter of the packing (see the table below). In that case, tighten
and lock the packing gland securely to prevent any leakage of explosive gas or flames.

10KD-5 Diffusion Type Detector
Cable outer
diameter
11 to 11.9

Packing holediameter
12

Washer holediameter
12

Packing holediameter
13
14
15

Washer holediameter
14
14
15

PE-2DC Suction Type Detector
Cable outer
diameter
12 to 12.9
13 to 13.9
14 to 14.9

11

4-4 Wiring and Connection(1) Gas Detector Wiring and Connection

WARNINGWhen wiring, be sure to turn off the indicator and alarm unit before opening the cover of Gas Detector,
otherwise it may become a source of ignition.
Be sure to ground the indicator alarm block along with the Gas Detector.

CAUTION
Check the terminal codes on the indicator alarm block and the Gas Detector block and wire the blocks
correctly.
Separate connection cables from power lines as far as possible.
Refer to the explosion-proof guidelines for factory electrical equipment for wiring the Gas Detector
connection.

1) Power Supply Wiring
Install a dedicated breaker to the power supply wiring for the indicator alarm block.

100 to 240V AC

Memo
Use round terminals for the wire ends in the indicator alarm block so that the wires will not be disconnected fromthe terminal block as a result of an earthquake or other vibration. Furthermore, provide a margin in the length ofeach wire so that no force will be directly imposed on the terminal block.
12

24V DC Input (with NVAL-52A Alarm Unit)

2) Wiring between Indicator Alarm Block and Gas Detector
Use 600V vinyl-insulated electric cords (1V) or cables, such as the VCT and CVV (0.75 to 2 mm2 in diameter).
The wiring length must be within the following ranges:
Wire with 0.75 mm2 dia.: 200 m max.
Wire with 1.25 mm2 dia.: 600 m max.
Wire with 2.00 mm2 dia.: 1 km max.

WARNING

Connect the Indicator Alarm Block and Gas Detector so that the channel numbers of each indicator Unit
coincide with the corresponding loop number seals of the Gas detector. The channel numbers of the
Indicator Unit are in alphabetical order with 1 from the leftmost side.

13

NV-4□□,500,600 Indicator Alarm Block(2) Connection of External Buzzer Contacts



CAUTIONUse external contacts for external buzzers or alarm indicators only.
Check that the load current or voltage will not be in excess of the contact capacity.
If interlock or other control is performed through the external buzzer contacts, we shall NOT take any
responsibility for any injury or damage caused.
1)

Alarm Unit
Lump alarm signal contacts: Non-voltage SPDT (2A resistive load at 100V AC)ＺＡ１ ＺＢ１ ＺＣ１(The NV-500 does not use ZA1, ZB1, or ZC1.)
Non-voltage SPDT (2A resistive load at 100V AC) ＺＡ２
External buzzer output: Voltage intermittent signal (10mA at 12V DC)ＺＢ２ ＺＣ２
ＢＺ Ｎ

The dedicated EB-5 External Buzzer can be connected to an external buzzer output.
Voltage output for centralized monitor panels (20mA at 0, 6, or 12V)

Ｌ Ｎ

The EB-700 Cosmos Centralized Monitor Panel can be connected to a centralized monitor panel output.
External reset (AR) and external buzzer stop (BS) terminal

ＡＲ ＢＳ Ｎ

By connecting an external switch, external buzzer reset and stop control will be possible.
2) Indicator Unit
Individual buzzer alarm output: Voltage output (20mA at 0､ 6､ or 12V)

Ｌ Ｎ

Individual alarm contacts  NV-4
Non-voltage SPST (2A resistive load 100V AC)
Non-voltage SPST (2A resistive load 100V AC)ＺＡ１ ＺＣ１ＺＡ２ ＺＣ２

 NV-500
Non-voltage SPST (2A resistive load 100V AC) ＺＡ

14ＺＣConnection examples of alarm output terminals.
 NV-4 or NV-600 Indicator Alarm Block NV-500 Indicator Alarm Block15

(3) Connection of the External Buzzer EB-5B
By connecting the Zener Barrier for external buzzer output, the EB-5 External Buzzer will have a safety
explosion-proof feature and can be used in hazardous places, such as gas filling sites.

CAUTION

The EB-5 External Buzzer itself does not have an explosion-proof construction. Do not use the EB-5 inhazardous places without the BT-150 Zener Barrier.
The BT-150 Zener Barrier needs to be grounded at a resistance not exceeding 10Ω.

Refer to 5. Indicator Alarm Circuit Diagram to add the safety explosion-proof feature to the External Buzzer.
Refer to the Operation Manual for information on using this feature.

16

5. Indicator Alarm Circuit Diagram
A standard circuit diagram is shown below. The circuit diagram may vary depending on the specifications. In
this case, refer to the relevant specifications.
5-1 100 to 240V AC Input
NV-4 or NV-600 Indicator Alarm Block17

NV-500 Indicator Alarm Block18

Ground

E

11 12

E

19

Note 1:Add the options if the safety explosion-proof feature is required.
2:The number of cable conductors varies with the Gas Detector model.

(Option)(ｵﾌﾟｼｮﾝ)

ZB1

CH.1

A
B
C
D

GroundGroundCH.n-1

Ground

E

L
N

A
B
C
D

PB

PA

ZA1

ZC1

ZA2

ZC2

Indicator Unit
NV-52U

6C cable(See note 2.)

A
B
C
D

PB

PA

ZA1

ZC1

ZA2

ZC2

L
N

A B C D
Suction Type
Detector
PE-2DCPA PB

Individual contacts
100 V AC
2A

Individual contacts
100 V AC
2A

Voltage output
0-6-12 V DC

CH.2

A B C
Diffusion
Type Detector
KD-5A
E
KD-5B

3C cable(See note 2.)

4C cable(See note 2.)

PB

A
B
C
D

PA

ZA1

PB

PA

ZA1

ZC1

ZA2

ZC1

ZC2

ZA2

L
N

ZC2

A B C D
Diffusion
Type Detector
KD-2A
E
KD-3A

Individual
contacts
100 V AC
2A
Individual
contacts
100 V AC
2A

L
N

Indicator Unit
NV-52U

Mother Board

Voltage output
0-6-12 V DCN BZExternal Buzzer
EB-5

Ground at a
resistance
not exceeding
10Ω

ZA1

N
ZC1

ZB2

ZC2

Lump
contacts
100 V AC
2A

Lump
contacts
100 V AC
2A

ZA2

BZ

BZ

Voltage output
0-6-12 V DC

Buzzercontacts
100 V AC
2A

N

BZ

L
N

AR External
reset
BS Externalbuzzer stopPN

N BZ E
External Buzzer
EB-5

2C
shield
cable

C D E

Zener Barrier
BT-150(Option)(See note 1.)

Power supply
24 VDC

Alarm Unit
NVAL-52A

NV-4□□andNV-600 Indicator Alarm Block

CH.n

5-2 24V DC Input

NV-4□□ or NV-600 Indicator Alarm BlockNV-500 Indicator Alarm Block20

6. Glossary
Indicator / Alarm unit:

A unit that receives signals from the gas detector and indicates gas concentration andalarms.

Detector:

A unit that detects gas concentration and converts it to electric signals.

Backup power source device:

A device that supplies power to the gas detector, indicator / alarm unit in order tomaintain its performance during a power failure.

Flow meter:

A meter to measure air flow in gas sampling pipe.

Gas collector:

A gas collecting probe that enhances gas collection efficiency and blocks water anddust.

Diffusion type:

A method to detect gas by utilizing convection and diffusion of gas.

Explosion proof construction:

A totally enclosed structure. When an explosive gas explodes in a container, thecontainer can resist the pressure and prevent the ignition of explosive gases outside ofit.

Preset alarm value:

A preset value for the alarm to go off when gas concentration reaches a certain value.

Gas to be detected:

Gas that is detected and indicated which sets off an alarm.

Detection range:

Range of gas’s concentration that can be indicated and set off an alarm.

Alarm accuracy:

Difference between the preset alarm value and gas concentration when an alarm
actually occurs or as the percentage of the difference compared to the preset alarm
value.

Response time:

Time it takes from when the gas detector is exposed to a gas with a concentration
higher (lower) than the preset alarm value until an alarm goes off.

Temperature range:

Range of temperature where the equipment can perform its functions.

Maintenance and inspections: Work to guarantee that the equipment perform its required functions.
Calibration gas:Gas used to calibrate scales of the equipment.

Peak hold:A function to constantly update and hold the peak value of input signals.

Hazardous area:

An area in a plant or facility with a dangerous atmosphere where explosive gases may
mix with air and explode or start a fire. An area where gas may be present.

Non hazardous area:

An area where electric equipment that has no potential to create a dagerous
atmosphere.

Dangerous atmosphere:

Atmosphere within the explosive limit where explosive gas and air are mixed.

LEL: Lower Explosive Limit.

The lowest concentration of flammable gas that will explode when mixed with air andignited.

(Quoted from gas detection terms and detector tube gas meter terms used by the Industrial Gas Detector Alarm
Association.)21

Manual Revision History
Edition No.
GAE-022

Date
Jan. 2006

Revisions00

Additional copies of this Operation Manual are available.
Contact the following address for ordering information.
Distributor:

Manufacturer:
New Cosmos Electric Co., Ltd.
2-5-4 Mitsuya-naka Yodogawa-ku
Osaka 532-0036, Japan
Phone 81-6-6309-1505
Fax 81-6-6309-1514
Email e-info@new-cosmos.co.jp
http://www.new-cosmos.co.jp

New Cosmos Electric Co., Ltd.

22