Riken Keiki NC-1000 User manual

PT0E-1382
Portable Combustible
Gas Detector
NC-1000
Operating Manual
(PT0-138)

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Contents
1. Outline of the Product..................................................................................................................................... 4
Preface............................................................................................................................................................ 4
Purpose of use................................................................................................................................................ 4
Definition of DANGER, WARNING, CAUTION and NOTE ............................................................................ 4
2. Important Notices on Safety........................................................................................................................... 5
2-1. Danger cases........................................................................................................................................... 5
2-2. Warning cases ......................................................................................................................................... 6
2-3. Precautions.............................................................................................................................................. 7
2-4. Safety information.................................................................................................................................... 9
3. Product Components....................................................................................................................................10
3-1. Main unit and standard accessories...................................................................................................... 10
3-2. Names and functions for each part .......................................................................................................12
4. How to Use ...................................................................................................................................................15
4-1. Before using the gas detector ...............................................................................................................15
4-2. Preparation for start-up .........................................................................................................................15
4-3. How to start the detector ....................................................................................................................... 18
4-4. Basic operating procedures................................................................................................................... 21
4-5. Performing air calibration ......................................................................................................................22
4-6. How to detect......................................................................................................................................... 23
4-7. Snap logger ...........................................................................................................................................26
4-8. Power-off ...............................................................................................................................................27
5. Display Mode Setting ...................................................................................................................................28
5-1. Entering display mode...........................................................................................................................28
5-2. Concentration displayed gas reading setting ........................................................................................31
5-3. Alarm setpoint display ...........................................................................................................................34
5-4. Pump suction volume setting ................................................................................................................36
5-5. Log data display .................................................................................................................................... 38
6. User Mode Setting........................................................................................................................................40
6-1. Entering user mode ............................................................................................................................... 40
6-2. Peak bar display setting ........................................................................................................................43
6-3. Date/time setting....................................................................................................................................44
7. Calibration ....................................................................................................................................................45
7-1. Preparation for air and span calibration ................................................................................................ 45
7-2. Entering calibration mode...................................................................................................................... 47
7-3. Bump test...............................................................................................................................................50
7-4. Air calibration .........................................................................................................................................52
7-5. AUTO CAL .............................................................................................................................................53
7-6. ONE CAL ...............................................................................................................................................55
7-7. Bump test condition setting ...................................................................................................................57
7-8. Password setting ...................................................................................................................................59
8. Alarm Function..............................................................................................................................................61
8-1. Gas alarm activation..............................................................................................................................61
8-2. Fault alarm activation ............................................................................................................................63
9. Maintenance .................................................................................................................................................64
9-1. Maintenance intervals and items...........................................................................................................64
9-2. How to clean ..........................................................................................................................................66
9-3. Parts replacement .................................................................................................................................67
10. Storage and Disposal .................................................................................................................................68
10-1. Procedures to store the gas detector or leave it for a long time .........................................................68
10-2. Procedures to use the detector again .................................................................................................68
10-3. Disposal of products ............................................................................................................................68
11. Troubleshooting ..........................................................................................................................................70
11-1. Abnormalities on unit ...........................................................................................................................70
11-2. Abnormalities of readings ....................................................................................................................71

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12. Product Specifications................................................................................................................................72
12-1. List of product specifications ...............................................................................................................72
12-2. Optional part list...................................................................................................................................73
13. Appendix .....................................................................................................................................................74
13-1. Definition of terms................................................................................................................................74

1. Outline of the Product Preface
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1
1. Outline of the Product
Preface
Thank you for choosing our portable combustible gas detector NC-1000 (hereinafter referred to as the gas
detector). Please check that the model number of the product you purchased is included in the
specifications on this manual.
This manual explains how to use the gas detector and its specifications. It contains information required for
using the gas detector properly. Not only the first-time users but also the users who have already used the
product must read and understand the operating manual to enhance the knowledge and experience before
using the gas detector.
Note that the contents of this manual are subject to change without notice for product improvement. It is
also prohibited to copy or reproduce this manual, in whole or in part, without permission.
Regardless of warranty period, we shall not make any indemnification for accidents and damage caused by
using the gas detector.
Make sure to read the warranty policy specified on the warranty.
Purpose of use
This product is used to detect combustible gases (ppm) in the air.
It provides two different specifications for target combustible gases: "general combustible gases (HC)"
used in ordinary factories, oil tankers, etc. and "methane (CH4)" such as city gas and natural gas.
Detection results are not intended to guarantee life or safety in any way.
Definition of DANGER, WARNING, CAUTION and NOTE
Throughout this manual, the following indications are used to ensure safe and effective work.
DANGER
This message indicates that improper handling may cause serious
damage on life, health or assets.
WARNING
This message indicates that improper handling may cause serious
damage on health or assets.
CAUTION
This message indicates that improper handling may cause minor
damage on health or assets.
NOTE This message indicates advice on handling.

2. Important Notices on Safety 2-1. Danger cases
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2
2. Important Notices on
Safety
To maintain the performance and use the gas detector safely, observe the following instructions of
DANGER, WARNING and CAUTION.
2-1. Danger cases
DANGER
About use
While conducting measurement in a manhole or confined space, do not lean over or look into
the manhole or closed space. It may lead to dangers because oxygen-deficient air or other
gases may blow out.
Oxygen-deficient air or other gases may be discharged from the gas exhausting outlet (GAS
OUT). Never inhale the air or gases.
High-concentration (10000 ppm or higher) gases may be discharged. Never use fire near it.

2. Important Notices on Safety 2-2. Warning cases
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2-2. Warning cases
WARNING
Sampling point pressure
The gas detector is designed to draw gases under the atmospheric pressure. If excessive
pressure is applied to the gas inlet (GAS IN) and outlet (GAS OUT) of the gas detector,
measuring gases may leak out from its inside and may cause dangerous conditions. Be sure
that excessive pressure is not applied to them while used.
Do not connect the gas sampling hose directly to a location with a pressure higher than the
atmospheric pressure. The internal piping system may be damaged.
Air calibration in atmosphere
When air calibration is performed in the atmosphere, check the atmosphere for freshness
before beginning it. If other gases exist, the adjustment cannot be performed properly, thus
leading to dangers when the gas leaks.
Response to gas alarm
Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based
on your judgment.
Battery level check
Before use, check that there remains sufficient battery power. When the gas detector is not
used for a long period, the batteries may be exhausted. Be sure to replace them with new ones
before use.
If a low battery voltage alarm is triggered, gas detection cannot be conducted. If the alarm is
triggered during use, turn off the power and promptly replace the batteries in a safe area.
Others
Do not throw the gas detector into fire.
Do not wash the detector in a washing machine or ultrasonic cleaner, etc.
Do not block the buzzer sound opening. No alarm sound can be heard.
Do not remove the batteries while the power is on.
Before turning on the power, check that the gas detector is connected to the gas sampling
probe and the surrounding air is fresh. When the gas detector is powered on, zero adjustment
is performed by air calibration automatically. Therefore, if the power is turned on under a gas
atmosphere, incorrect gas concentration will be displayed.
If the main unit is dropped or given a shock, the reading may remain high. In this case, perform
air calibration in a location with fresh atmospheric air.

2. Important Notices on Safety 2-3. Precautions
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2-3. Precautions

2. Important Notices on Safety 2-3. Precautions
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2. Important Notices on Safety 2-4. Safety information
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2-4. Safety information
Outline of the product
The combustible gas detector model NC-1000 is designed to detect leakage of combustible gases in a
hazardous area continuously.
The detection range of NC-1000 is 0 to 10,000 ppm.
A sample of gas is drawn by the internal small pump.
Only AA alkaline dry batteries (LR6, four pieces, manufactured by TOSHIBA) are used for power supply.
The dry batteries cannot be replaced in a hazardous area.
Technical data
Explosion-proof
specifications
Explosion-proof
class
ExiaIICT4Ga
II 1GExiaII CT4Ga
Surrounding
temperature
range
-20 - +50ºC
Electrical
specifications Driven by four AA alkaline dry batteries (LR6, manufactured by
TOSHIBA)
Certificate
number
IECEX
ATEX
Applied
standards
IEC60079-0：2011
IEC60079-11:2011
IEC60079-26:2006
EN60079-0:2012
EN60079-11:2012
EN60079-26:2007
Precautions
• Do not replace dry batteries in a hazardous area.
• Do not disassemble/modify the devices.
• Use only AA alkaline dry batteries (LR6, manufactured by TOSHIBA)
for power supply.
• Use only CR1220 (manufactured by Hitachi Maxell) for backup
power supply.
How to read
instruction
number
INST.No. 0 0 000 0000 00
A B C D E
A: Manufacturing year (0 - 9)
B: Manufacturing month (1 - 9, XYZ for Oct. to Dec.)
C: Manufacturing lot
D: Serial number
E: Factory code
Manufacturer
RIKEN KEIKI CO., LTD.
2-7-6 Azusawa, Itabashi-ku, Tokyo, 174-8744 Japan
Web site: http://www.rikenkeiki.co.jp/

3. Product Components 3-1. Main unit and standard accessories
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3
3. Product Components
3-1. Main unit and standard accessories
After opening the package, check the gas detector and accessories.
If anything in the following list is not included, contact RIKEN KEIKI.
Main unit
For names and functions of individual parts of the gas detector and LCD display, see "Names and functions
for each part" (P. 12).
<Main Unit>
Accessories
AA alkaline
dry batteries: 4
(installed)
Gas sampling probe and
gas sampling hose (1 m)
: 1
Hand strap: 1 Product warranty: 1
Operating manual: 1

3. Product Components 3-1. Main unit and standard accessories
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DANGER
About explosion-proof
Do not modify or change the circuit, structure, etc.
When using the gas detector in a hazardous area, take the following countermeasures for
preventing dangers resulting from electrostatic charges.
(1) Wear anti-static clothes and conductive shoes (anti-static work shoes).
(2) For indoor use, use the gas detector while standing on a conductive work floor (with a
leakage resistance of 10 MΩor less).
Replace the batteries in a non-hazardous area.
The rated values of the gas detector
Power supply: 6.0 VDC (LR6, four pieces, manufactured by TOSHIBA) Ambient temperature:
-20 - +50ºC
The explosion-proof class of the gas detector
ExiaIICT4 (TIIS explosion-proof certification)
II 1GExiaII CT4Ga (ATEX explosion-proof directive)
The protection class of case
IP20

3. Product Components 3-2. Names and functions for each part
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3-2. Names and functions for each part
This section describes names and functions of main unit and battery unit parts and LCD display.
<Appearance of Main Unit>
No. Name Function
(1) LCD display Displays gas concentrations, measured gas names, alarms, etc.
(2) Buzzer sound opening Emits operation and alarm sounds. (Do not block it.)
(3) Alarm lamp window Blinks (in red) in response to an alarm.
(4) Calibration/▲button Keep this button pressed to perform air calibration.
(5) ALARM reset/▼button When an alarm occurs, press this button to reset the alarm.
(6) Display switching button Press this button to change the display.
(7) Power/set button Turns the power ON/OFF.
(8) Gas inlet Connect a gas sampling hose to this port.
(9) Gas outlet Exhausts the gas drawn into the gas detector. (Do not block it.)
(10) Lock plate Retains the battery cover.
(11) Battery cover Protects the battery.
(1) LCD display
(8) Gas inlet
(9) Gas outlet
(11) Battery cover
(10) Lock plate
(2) Buzzer sound
opening
(3) Alarm lamp
window
(6) Display
switching
button
(7) Power/
set button
(4) Calibration/▲
button
(5) Alarm reset/▼
button

3. Product Components 3-2. Names and functions for each part
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<LCD Display>
No. Name Function
(1) Operating state display Displays the operating status in the detection mode. Normal: Blinking
(2) Flow check display Displays the drawing status. Normal: Rotating
(3) Range mode display Displays an icon of Lo/Hi/Auto indicating range mode.
(4) Battery level icon Displays a reference of the battery level.
(5) Gas name display Displays detected gases name.
(6) Concentration and unit
display
Displays gas concentration and unit.
(7) Full scale and bar
display
Displays the level of gas concentration with the bar meter as well as
the full scale value.
(8) Clock display Displays the current time.
NOTE
The meanings of battery level icons are as follows:
: Sufficient / : Low / : Needs charging
If the battery level is lower than the above, the inside of the battery icon starts to blink ( ).
Range mode display
• Lo: Fixed to the low range (0 - 1000 ppm)
• Auto: Automatic switch between the low and high ranges
• Hi: Fixed to the high range (0 - 10000 ppm)
(8) Clock display
(7) Full scale
and bar display
(6) Concentration and
unit display
(5) Gas name display
(1) Operating state
display
(2) Flow check
display
(3) Range mode
display
(4) Battery level icon

3. Product Components 3-2. Names and functions for each part
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Gas sampling probe and gas sampling hose
No. Name Function
(1) Gas sampling probe Placed in a detection area to collect a gas.
The probe includes a dust filter.
(2) Gas sampling hose A resin hose through which the sampled gas goes.
(3) Hose clamp coupler A joint that connects with the main unit.
差し替え
(3) Hose
clamp
coupler
(2) Gas sampling hose
(1) Gas sampling probe

4. How to Use 4-1. Before using the gas detector
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4
4. How to Use
4-1. Before using the gas detector
Not only the first-time users but also the users who have already used the gas detector must follow the
operating precautions.
Ignoring the precautions may damage the unit, resulting in inaccurate gas measurement.
4-2. Preparation for start-up
Before starting gas detection, check the followings.
Check that the protective film attached on the display from shipping is removed
The batteries are installed (with sufficient battery level).
The dust filter is not contaminated.
The gas sampling probe is not loose.
The hose clamp coupler is connected securely.
4-2-1. Battery replacement procedure
When the gas detector is used for the first time, or when the battery level is low, attach new AA alkaline
batteries according to the following procedures.
1 Check that the power of the
gas detector is turned off.
Turn off the power if it is turned on.
2 Release the lock and open
the battery cover.
Lock plate
CAUTION
The display is covered by the protective film to prevent scratches from shipping.
Be sure to remove this film before use.
Gas monitor with this film will not satisfy the explosion-proof performance.

4. How to Use 4-2. Preparation for start-up
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3 Remove old batteries and
then put new batteries
while observing the correct
polarity.
4 Close the battery cover and
lock it.
A clicking sound is heard when the
cover is locked.
4-2-2. Gas sampling probe maintenance
Check the dust filter inside the gas sampling probe visually.
• Check that the dust filter is not contaminated.
<Dust Filter Replacement Procedure>
Check the dust filter inside the gas sampling probe for contamination visually.
If the dust filter is contaminated, replace it following the procedure below.
1 Hold the middle section
(filter case) of the gas
sampling probe and remove
the tip section by turning it
counterclockwise.
CAUTION
Be sure to turn off the power of the gas detector before replacing the batteries.
Replace the batteries in a safe area.
Replace all the four batteries with new ones at one time.
Pay attention to the polarities of the batteries in replacing.
If the battery cover is not completely locked, the dry batteries may drop off or water may get in
through the clearance. Water may also get in if a minute foreign substance is caught beneath
the battery cover.
DANGER
The requirements of explosion-proof standard of the gas detector include the use of TOSHIBA
dry batteries. To use the unit as an explosion-proof product, use four AA alkaline dry batteries
(LR6) manufactured by TOSHIBA CORPORATION.
Battery cove
r

4. How to Use 4-2. Preparation for start-up
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2 Remove the contaminated
dust filter from the middle
section (filter case) and
then put a new filter in the
case.
There are no differences between
the front and back sides of the dust
filter.
3 Connect the tip section by
turning it clockwise.
Tighten it securely. Loose connection
may cause a leak.
Tighten it by hand.
<Assembly>
Connect the gas sampling probe to the main unit as shown in the following figure.
Insert the hose clamp coupler into the gas inlet of the main unit while pulling the release ring, and then
release the release ring.
NOTE
To connect the hose release coupler to the gas inlet (GAS IN), push the coupler until it clicks.
CAUTION
Use only a gas sampling hose specified by RIKEN KEIKI.
Use the gas detector with the gas sampling probe connected to the gas sampling hose so that
no foreign substance is drawn into the gas sampling hose.
Be sure to connect the gas sampling probe to the gas sampling hose by hand. If they are
fastened too tightly using a tool, the plastic part of the gas sampling probe may be broken.
Main unit
Release ring
(hose clamp coupler)
Dust filter

4. How to Use 4-3. How to start the detector
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4-3. How to start the detector
When the power is turned on, a self-diagnostic starts, and then the gas detector enters the detection mode.
Power-on
Press and hold the POWER button until the buzzer blips (one second or longer) to turn on the power.
When the power is turned on, the LCD display changes automatically as shown below, and the gas
detector enters the detection mode.
1 Press and hold the
POWER button for one
second or longer.
Hold down the
button until all
LCDs light up,
the alarm lamp
lights up, and
the buzzer blips.
All LCDs light
up.
▼
Date/time
display
Display example:
Monday, June 01, 2015
8:30
▼
Battery voltage
display
Alarm type
display
Display example:
Battery voltage: 6.0 V
Alarm type: AL-H (self-latching)
* Alarm type
Self-latching: AL-H (Alarm-Hold)
Auto-reset: AL-A (Alarm-Auto)
▼
Gas name
display
Display example:
CH4
▼

4. How to Use 4-3. How to start the detector
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Full scale
Display
Display example:
10000 ppm
▼
WARNING
setpoint
display
Display example:
250 ppm
▼
ALARM
setpoint
display
Display example:
500 ppm
▼
Automatic air
calibration
Display
▼
The buzzer blips
once and the
detection mode
is displayed.
Detection
mode

4. How to Use 4-3. How to start the detector
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NOTE
The range mode used at the last power off is retained.
If there is an abnormality in the built-in clock, a fault alarm "FAIL CLOCK" may be triggered. In this
case, contact RIKEN KEIKI immediately.
WARNING
Before turning on the power, check that the gas detector is connected to the gas sampling
probe and the surrounding air is fresh. When the gas detector is powered on, zero adjustment
is performed by air calibration automatically. Therefore, if the power is turned on under a gas
atmosphere, incorrect gas concentration will be displayed.
If automatic air calibration is not performed normally at power-on, presence of some gas in the
power-on environment is suspected. In this case, turn off the power and then turn it on again in
an environment with fresh atmospheric air. If the situation does not improve after several times
of power cycling, there may be a problem in the sensor. Contact RIKEN KEIKI immediately.
Gas measurement cannot be performed with a faulty sensor.
If the main unit is dropped or given a shock, the reading may remain high. In this case, perform
air calibration in a location with fresh atmospheric air.