RIKEN KEIKI Portable Oxygen Monitor OX-07 (TYPE A)
Operating Manual
RIKEN KEIKI Co., Ltd.
2-7-6 Azusawa, Itabashi-ku, Tokyo, 174-8744, Japan
Phone: +81-3-3966-1113
Fax: +81-3-3558-9110
E-mail: intdept@rikenkeiki.co.jp
Web site: http://www.rikenkeiki.co.jp/
Safety Information
The Portable Oxygen Monitor Model OX-07 is a monitor designed to provide continuous exposure monitoring of Oxygen (O2) in hazardous environments.
Specification for safety
- Ex ia IIC T4 Ga
- II 1G Ex ia IIC T4 Ga
- Ambient temperature range for use: -20°C to +50°C
Electrical data
- Powered by two AA size Alkaline batteries, model LR-6 by Toshiba.
Certificate numbers
- IECEx Certificate number: IECExKEM08.0022
- ATEX Certificate number: KEMA08ATEX0126
List of standards
- IEC 60079-0:2011, IEC 60079-11:2011, IEC 60079-26:2006
- EN60079-0:2012, EN60079-11:2012, EN60079-26:2007
WARNING
- Do not replace batteries in hazardous location.
- Do not replace O2 sensor in hazardous location.
- Do not replace Extension Cable in hazardous location.
- Do not attempt to disassemble or alter the instrument.
INST. No. Details
INST. No. [Sequence of characters for year, month, lot, serial, factory code]
- A: Manufacturing year (0-9)
- B: Manufacturing month (1-9, XYZ for Oct.-Dec.)
- C: Manufacturing lot
- D: Serial number
- E: Code of factory
Introduction
Using an advanced microprocessor controlled detection system, the OX-07 Oxygen Monitor detects the Oxygen (O2) content to prevent accidents caused by oxygen deficiency.
This manual is a guide to operation of the OX-07. Reading of this manual is requested not only for first-time users but also for experienced staff.
This manual contains the following headings to ensure safe and effective operation:
- DANGER: Indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury or serious damage to the product. This signal word is to be limited to the most extreme situation.
- WARNING: Indicates a potentially hazardous situation which, if not avoided, could result in serious injury to the human body or object.
- CAUTION: Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury or some damage to the human body or objects. It may also be used to alert against unsafe practices.
- NOTE: This means "ADVICE" regarding operation.
Cautions for Safety
WARNING
- Perform gas calibration at proper intervals.
- Do not use unspecified batteries.
- Check battery capacity before operation.
- Ensure that the sensor is exposed to ambient air. If not, correct detection cannot be performed.
- Do not modify or change the circuit or structure.
- Do not disassemble the sensor as it contains an electrolyte. If your finger touches the electrolyte, wash your finger with water immediately.
- If buttons are pushed randomly, settings may change, and alarms may not be activated correctly. Operate buttons only as per instructions.
- Do not drop this monitor into fire.
- Do not remodel or alter circuit/structures.
- Do not use or store the unit in high temperature, high humidity, or high pressurized conditions exceeding the specified operating conditions. Correct measurement may not be performed.
CAUTION
- Do not push the sensor and buzzer window with a pointed article. This may cause defects or damage, and correct detection cannot be performed.
- Do not pour water on this monitor or immerse it in water.
- Do not subject the unit to high impact or shock, as it is a precision instrument.
- The operating temperature range of this monitor is -20 to +50°C. Readings may be affected by sudden temperature changes if the monitor is used under such conditions.
- Remove the battery if the monitor is not used for a long period.
Cautions relating to explosion proof
WARNING
- Do not remodel or alter circuit/structures.
- Replace batteries in a non-hazardous area.
- When using this gas monitor in a hazardous area, take the following countermeasures for preventing dangers resulting from electrostatic charges:
- Wear anti-static clothes and conductive shoes (anti-static work shoes).
- For indoor use, use the gas monitor while standing on a conductive work floor (with a leakage resistance of 10 MΩ or less).
- Do not use this monitor except for the measurement of air and for oxygen content measurement of gas mixtures.
1. DESIGNATION
Front view
A diagram shows the front of the portable oxygen monitor with the following labeled components:
- 1. LCD display: Indicates gas detection results and various information.
- 2. AIR button: Adjusts readings when a fresh air adjustment is performed. Changes a parameter setting when a parameter is available for adjustment in display mode or setup mode.
- 3. Target gas window: Window to see the target gas described by the sensor.
- 4. Alarm light: Flashes when the unit reaches warning conditions.
- 5. POWER button: Turns the unit on and off.
- 6. DISP button: Enters setup mode. Determines a parameter in setup mode. Changes a parameter setting in setup mode.
- 7. Buzzer: Sounds for gas alarms, unit malfunctions, and dead battery alarms.
Rear view
A diagram shows the rear of the unit, indicating:
- 8. Threaded holes: Used to mount the alligator clip or the optional belt clip.
Bottom view
A diagram shows the bottom of the unit, indicating:
- 9. Battery cover: The cover for the battery compartment.
- 10. Sensor: The oxygen sensor is mounted here.
LCD display (Measuring mode)
A diagram illustrates the LCD display in measuring mode:
- 11. Target gas: Displays the name of the target gas (e.g., O2).
- 12. Battery icon: Shows remaining battery life.
- 13. Gas concentration & status indication: Displays the target gas concentration and the status of the unit.
- 14. Unit: Indicates the unit of gas concentration (e.g., %).
2. PREPARATION
2-1. Mounting/Replacing the batteries
- Verify that the unit is off.
- Rotate the fastener in the battery cover a quarter turn counterclockwise and lift up the end of the battery cover to remove it. A coin may be used to rotate the fastener.
- Carefully install the new AA alkaline batteries, following the battery diaphragm inside the battery compartment.
- Reinstall the battery cover.
Diagrams illustrate opening, closing, and the direction of battery mounting for AA size alkaline batteries.
WARNING: Do not remove the battery with power on. Battery replacement shall be done at power-off condition.
CAUTION: Take care not to mistake the direction of battery polarity.
2-2. Mounting/Replacing the sensor
When replacing the sensor, take care for the following points:
CAUTION:
- After replacement of the sensor, be sure to perform the sensor calibration. If not, the reading may be deviated.
- If the unit is not used for a long period, be sure to perform the sensor calibration before use.
- Replace the sensor if you can no longer perform AIR calibration or when the reading is unstable.
- Sensor replacement shall be done at power-off condition.
Diagrams show the sensor and the process of aligning the yellow line on the rubber guard with the "UNLOCK" and "LOCK" indicators on the instrument body for sensor retainer removal and mounting.
- Verify that the unit is off.
- Turn the rubber guard on the sensor retainer counterclockwise until the yellow line on the rubber guard aligns with the "UNLOCK" line on the instrument body.
- Pull the sensor retainer away from the instrument body.
- Pull the old sensor out from the sensor retainer.
- Replace the sensor with a new one. Match the concave part of the sensor connector with the convex part of the sensor mounting.
- Align the yellow line on the sensor retainer's rubber guard with the "UNLOCK" line on the case, insert it deeply, and turn the rubber guard to the "LOCK" line.
2-3. Power ON/OFF
Press and briefly hold the POWER button for about one second to turn on the OX-07.
NOTE: Press and hold the POWER button until you hear a beep.
DANGER: Be sure to perform a fresh AIR adjustment before using the OX-07 (See section 3-2).
In any mode, the power is turned off by pressing and holding the POWER button for about 3 seconds.
NOTE: Press and hold the POWER button until the LCD turns off. This typically takes about 3 seconds, indicated by three beeps.
3. OPERATION
3-1. Start-up procedure
When the OX-07 is turned on, it enters measuring mode automatically. The concentration of the target gas is displayed on the LCD. The start-up procedure takes about 15 seconds and involves displays for Power on, Target gas, Battery voltage, Full scale, Warning level, and Alarm level, before starting measurement.
NOTE: The operating temperature range of this unit is -20 to +50°C. However, oxygen concentration readings may fluctuate if the ambient temperature changes suddenly.
3-2. Performing a fresh air adjustment
Before using the OX-07, set the fresh air reading. Performing this adjustment ensures accurate gas readings in the monitoring environment.
- Find a fresh air environment, which typically has a normal oxygen content of 20.9%.
- With the unit on and in measuring mode, press and hold the AIR button. The LCD displays "hold" prompting you to hold the button.
- After a moment, the LCD indicates "Adj". Continue to hold the AIR button.
- Release the AIR button when the LCD displays "RELEASE" in the upper left corner.
- About 2 seconds later, the LCD indicates "FINISH" in the upper left corner and returns to measuring mode, showing that the fresh air adjustment has been completed automatically.
Diagrams illustrate the sequence of button presses and LCD feedback for this procedure.
NOTE: Fresh air adjustment can be performed even in gas alarm condition. If an "AIR CAL FAIL" error is issued, release the alarm by pressing and holding the AIR button for about 3 seconds, then release it when "RELEASE" is displayed. After about 4 seconds, the adjustment is cancelled, and "FINISH" is displayed with the concentration before the adjustment.
DANGER: Perform air adjustment in fresh air atmosphere under similar pressure, temperature, and humidity conditions to the operating environment. If air adjustment is done at a detection place where oxygen deficiency may occur, correct gas detection cannot be performed, and an oxygen deficiency accident may take place.
3-3. Changing the display in measuring mode
You can change the display mode by pressing the DISP button in measuring mode. This allows viewing the current gas concentration, the peak (lowest) gas reading, and the peak (highest) gas reading. Pressing the DISP button cycles through these views.
You can also change the display mode by pressing the AIR button when viewing peak readings, allowing access to warning level set points and alarm level set points.
NOTE: If no button is pressed for about 20 seconds while in display mode, the unit will return to measuring mode automatically. The backlight will turn off 20 seconds after the last button press. Pressing any control button turns the LCD backlight on. The unit can be turned off by pressing and holding the POWER button for about 3 seconds in any display mode.
NOTE: About minus sign: If the gas reading in measuring mode falls more than 2% of full scale below zero, the LCD displays a "-" (minus sign) in front of the single figures of the LCD.
3-4. Wearing the unit
The unit can be used by attaching the standard alligator clip or the optional belt clip.
WARNING: Ensure that the sensor is exposed to ambient air. If not, correct detection cannot be performed and it may lead to an accident.
Mounting the alligator clip
- Screw down the adaptor for the alligator clip on the back of the case (2 points).
- Fix the alligator clip to the adaptor with 2 screws.
- Adjust the direction of the alligator clip with the teeth in the alligator clip's jaws opened.
Diagrams show the adaptor, alligator clip, and screws.
Mounting the belt clip
Screw down the belt clip on the back of the case (2 points).
Diagrams show the belt clip and screws.
4. ALARMS
4-1. Types and patterns of gas alarm
The OX-07 will sound an alarm, flash its alarm lights, and vibrate when the oxygen concentration reaches the warning/alarm level.
For Japanese specification
- Gas alarm types: Low alarm (WARNING), Low-Low alarm (ALARM), Over range alarm (OVER).
- Alarm patterns: Pattern "A", Pattern "B".
- Alarm actions: Buzzer, light, vibration, LCD (flashing, back light on).
| Alarm types | Target gas | Alarm pattern | |
|---|---|---|---|
| Low alarm (WARNING) | O2 | 18.0vol% | Pattern A |
| Low-Low alarm (ALARM) | O2 | 18.0vol% | Pattern B |
| Over range alarm (OVER) | O2 | 40.0vol% | Pattern B *1 |
For Overseas specification
- Gas alarm types: Low alarm (WARNING), High alarm (ALARM), Over range alarm (OVER).
- Alarm patterns: Pattern "A", Pattern "B".
- Alarm actions: Buzzer, light, vibration, LCD (flashing, back light on).
| Alarm types | Target gas | Alarm pattern | |
|---|---|---|---|
| Low alarm (WARNING) | O2 | 19.5vol% | Pattern A |
| High alarm (ALARM) | O2 | 23.5vol% | Pattern B |
| Over range alarm (OVER) | O2 | 40.0vol% | Pattern B *1 |
*1. Actions of buzzer, light, and vibration are the same as for ALARM. Only the display screen is different.
Actions of alarm lights, buzzer sound and vibration
Diagrams illustrate the patterns:
- Alarm pattern: Pattern A (Intermittent: Once per second), Pattern B (Intermittent: Twice per second).
- Buzzer sound (Pulsing tone): Shows waveform for Pattern A (Pi-) and Pattern B (Pi Pi).
- Alarm lights: Shows flashing patterns.
- Vibration: Shows vibration patterns.
Examples of LCD indication
Diagrams show LCD indications for WARNING (gas reading flashes), ALARM (gas reading flashes), and OVER (gas reading replaced by blinking brackets).
NOTE: If an alarm is issued, the LCD changes to alarm indication automatically.
4-2. Resetting gas alarms
To reset a gas alarm or trouble alarm, press and release the POWER button.
Alarms to be able to reset:
- Gas alarm
- Calibration failure
Alarms unable to reset:
Following alarms cannot be reset unless you turn off the unit:
- System failure
- Dead battery alarm
- Sensor failure
NOTE: The alarm pattern of this unit is a latched mode. Even though the gas concentration may have returned to normal or may have increased above the low alarm point, or may have fallen below the high alarm point, the alarm indications will continue until you have reset the alarm using the POWER button.
4-3. Responding to gas alarms
Gas alarms are set at safety levels. However, sudden release of gas can exceed safety levels and reach dangerous levels within a short time. If an alarm is activated, leave the area immediately and ventilate it. Also, stop the leaking source immediately if the gas leak is identified.
DANGER: If an oxygen gas alarm is activated, ventilate with fresh air or escape to the fresh atmosphere immediately. It may lead to dangers because oxygen-deficient air or other gases may blow out.
4-4. Other alarms
System failure
Diagram shows LCD displaying "CIRCUIT FAIL". Buzzer sounds, alarm light flashes, gas reading is replaced by "CIRCUIT FAIL", and back light turns on.
Sensor failure
Diagram shows LCD displaying "SENSOR FAIL". Buzzer sounds, alarm light flashes, gas reading is replaced by "SENSOR FAIL", and back light turns on.
NOTE: Sensor failure may be activated at the time of AIR calibration. To reset an alarm, press the POWER button. In this case, AIR calibration is not performed. If sensor failure is activated except for system failure, low battery alarm, or at the time of AIR calibration, only power-off operation can be performed. When sensor failure or system failure has occurred, turn off the power and contact an authorized agent.
4-5. Responding to dead battery alarm
Diagram shows LCD displaying "BATTERY FAIL". Buzzer sounds, alarm light flashes, battery icon flashes, gas reading is replaced by "BATTERY FAIL", and back light turns on.
NOTE: The standard of the bar in the battery icon is as follows:
- [Full bar]: Enough remaining.
- [Half bar]: Battery capacity has been decreased.
- [Empty bar]: Change the battery as soon as possible.
WARNING: The unit is not operational as a gas monitor. Change the battery as soon as possible when a low battery warning occurs.
5. MAINTENANCE AND CHECK
Perform the following checks to maintain the reliability and correct functions.
WARNING: If you find any abnormality with this unit, contact your authorized agent.
5-1. Daily check
Check that the unit housing, display, switches, and lights are not dirty or damaged. Also, check battery voltage and the actions of the buzzer, lights, and vibration when turning the power on.
5-2. AIR calibration (Fresh air adjustment)
Perform AIR calibration after power on. Also, perform AIR calibration in fresh atmosphere if the O2 reading is not 20.9% (See section 3-2).
5-3. Replacing batteries
Replace the battery if the battery voltage decreases during operation (See section 2-1).
5-4. Gas calibration
It is required to perform gas calibration at minimum every 6 months. To calibrate the unit, you will need the calibration kit. Ask your authorized agent for the gas calibration kit.
6. SCRAP THE PRODUCT
As harmful substances or materials for the environment are not used in this unit itself, treat it as industrial waste (non-flammable material) according to local rules. Regarding the oxygen sensor, contact your nearest agent or RIKEN KEIKI CO., LTD.
7. TROUBLESHOOTING
| Symptoms | Probable causes | Recommended action |
|---|---|---|
| The unit will not turn on | Batteries may need to be replaced. Battery polarity may be wrong. Holding time for POWER button may be too short. Battery cover may be loose. | Refer to section 2-1 Mounting /replacing the batteries. Press and hold POWER button for about 1 sec until it shows display. Verify that the battery cover is attached. |
| "CIRCUIT FAIL" is displayed on the LCD | A circuit failure has occurred. | Contact your nearest agent to repair. |
| "SENSOR FAIL" is displayed on the LCD | The O2 sensor may need replacement. | Replace the sensor with a new one. |
| "AIR CAL. FAIL" displays during fresh air adjustment | Fresh air is not supplied to the unit. | Supply fresh air. |
| "BATTERY FAIL" is displayed on the LCD | The O2 sensor may need replacement. Decrease of battery voltage. | Replace the sensor with a new one. Turn off the unit and replace batteries with new ones in a non-hazardous area. |
8. SPECIFICATIONS
8-1. Specifications
Japanese specifications
| Parameter | Specification |
|---|---|
| Model | OX-07 |
| Type | TYPE A |
| Detectable gas | Oxygen |
| Detection principle | Galvanic cell |
| Measuring range | 0~40vol% (Resolution: 0.1vol%) |
| Low alarm | 18.0vol% |
| Low-Low alarm | 18.0vol% |
| Over alarm | 40.0vol% |
| Various indications | Battery icon |
| Indicate accuracy (under an identical condition) | Within ±0.7vol% |
| Response time (under an identical condition) | Within 20 seconds(T90) |
| Gas alarm indication | Flashing light/Intermittent buzzer/Gas reading flashes/Vibration |
| Gas alarm action | Latching-mode |
| Trouble alarm•Self diagnosis | System failure/Sensor failure/Low battery/Calibration error |
| Trouble alarm indication | Flashing light/Intermittent buzzer/Content display |
| Trouble alarm action | Latching mode |
| Detection method | Diffusion method |
| Gas concentration display | LCD digital display |
| Power supply | Alkaline batteries (Size AA) × 2 pcs. |
| Continuous operation time | About 5000 hours (no alarm·no light at 25°C) |
| Explosion-proof structure | Intrinsically safe |
| Explosion-proof grade | Ex ia II CT3X (TIIS |
| Operating temperature and humidity | -20~50℃, below 95%RH (non-condensing) |
| Operating pressure | Atmospheric pressure (80kPa~110kPa) |
| Various functions | LCD backlight/Peak hold display |
| Outer dimension and Weight | Approx. 66(W) × 114(H) × 33(D)mm (Projection excluding) Approx. 230g (Excluding clip) |
Overseas specifications
| Parameter | Specification |
|---|---|
| Model | OX-07 |
| Type | TYPE A |
| Detectable gas | Oxygen |
| Detection principle | Galvanic cell |
| Measuring range | 0~40vol% (Resolution: 0.1vol%) |
| Low alarm | 19.5vol% |
| High alarm | 23.5vol% |
| Over alarm | 40.0vol% |
| Various indications | Battery icon |
| Indicate accuracy (under an identical condition) | Within ±0.7vol% |
| Response time (under an identical condition) | Within 20 seconds(T90) |
| Gas alarm indication | Flashing light/Intermittent buzzer/Gas reading flashes/Vibration |
| Gas alarm action | Latching-mode |
| Trouble alarm▪ Self diagnosis | System failure/Sensor failure/Low battery/Calibration error |
| Trouble alarm indication | Flashing light/Intermittent buzzer/Content display |
| Trouble alarm action | Latching mode |
| Detection method | Diffusion method |
| Gas concentration display | LCD digital display |
| Power supply | Alkaline batteries (Size AA) × 2 pcs. |
| Continuous operation time | About 5000 hours (no alarm·no light at 25°C) |
| Explosion-proof structure | Intrinsically safe |
| Explosion-proof grade | II 1G Ex ia II CT4Ga (ATEX/IECEx |
| Operating temperature and humidity | -20~50℃, below 95%RH (non-condensing) |
| Operating pressure | Atmospheric pressure (80kPa~110kPa) |
| Various functions | LCD backlight/Peak hold display |
| Outer dimension and Weight | Approx. 66(W) × 114(H) × 33(D)mm (Projection excluding) Approx. 230g (Excluding clip) |
8-2. Standard accessories
| Items | Japanese specifications (with 5m cable) | Japanese specifications (Personal) | Overseas specifications |
|---|---|---|---|
| AA size alkaline batteries | 2pcs | - | - |
| Alligator clip (with adaptor 1pce/screws 4pcs) | ○ | ○ | ○ |
| Hand strap | ○ | - | - |
| Carrying case | ○ | ○ | ○ |
| Extension cable (5m) | ○ | - | - |
| Operating manual | ○ | ○ | ○ |
8-3. Optional accessories
- Belt clip (with 2 screws)
- Extension cable (5m, 10m, 20m, 30m)
- Carrying case
Diagrams show the belt clip and extension cable.
Using the OX-07 with extension cable
- Verify that the OX-07 is off.
- Take out the sensor from the instrument body.
- Mount the removed sensor to the sensor retainer with the same procedures as sensor mounting (See section 2-2).
- Mount the cable retainer to the instrument body as shown in the figure, and align the yellow line with the "LOCK" line.
Diagrams illustrate the sensor retainer and cable retainer attachment.
CAUTION:
- When using the OX-07 with an extension cable, do not throw the sensor part into the detection point, but lower it down slowly. Avoid impact to the sensor, as it may be damaged.
- When intending to measure the oxygen content in a manhole, inside a device, etc., by OX-07 with an extension cable, adjust the temperature of the sensor to be the same temperature as the measuring point by leaving it there for about 10 minutes. Then, pull it up to the ground once, turn on the unit again, and perform the fresh air adjustment. After that, lower the sensor down to the detection point and measure oxygen content.
9. DEFINITION OF TERMS
- vol%: Gas concentration represented by the unit as a percentage of the total volume.
- Calibration: By using calibration gas, adjust the displayed gas concentration to match the calibration gas concentration.
- PEAK: This is a peak (highest or lowest) gas reading since the last time the unit was turned on.
- Warning/Alarm level set point: Preset level to actuate an alarm when gas concentration reaches that point.
- Maintenance and check: Work and inspection to maintain the performance of this unit.
10. DETECTION PRINCIPLE
By connecting a noble metal and lead immersed in an electrolyte with a lead wire, an electrochemical cell (galvanic cell) is made. A membrane covers the cell and allows oxygen to diffuse into the electrolyte, where reduction on the metal electrode and oxidation on the lead electrode occur, respectively, as shown in the following chemical equations:
- Cathode (noble metal): O2 + H2O + 4e⁻ → 4OH⁻
- Anode (lead): 2Pb → 2Pb²⁺ + 4e⁻
The oxygen reacts in the cell as per the above equation and produces a current proportional to the oxygen concentration. The current develops a voltage across a thermistor/resistor network. If oxygen concentration decreases, reduction on the noble metal electrode decreases, and the voltage on both sides of the thermistor also decreases.
[Structure]
A diagram shows the structure of the electrochemical cell, including the Membrane, Cathode, Electrolyte, Anode, Output terminal, and Thermistor.
Declaration of Conformity
RIKEN KEIKI CO., LTD.
2-7-6, Azusawa, Itabashi-ku, Tokyo 174-8744 Japan
declare in our sole responsibility that the following product conforms to all the relevant provisions.
- Product Name: Portable Gas Monitor
- Model Name: OX-07
- Council Directives:
- EMC: 2004/108/EC (Until 19 April 2016), 2014/30/EU (From 20 April 2016)
- ATEX: 94/9/EC (Until 19 April 2016), 2014/34/EU (From 20 April 2016)
- RoHS: 2011/65/EU
- Applicable Standards:
- EMC: EN 50270(2006)
- ATEX: EN 60079-0(2012):A11(2013), EN 60079-11(2012), EN 60079-26(2007)
- RoHS: EN 50581(2012)
Name and address of the ATEX Notified Body: DEKRA Certification B.V., Utrechtseweg 310, 6812 AR Arnhem, The Netherlands.
Number of the EC type examination certificate: KEMA08ATEX0126, Jan 24, 2014.
Name and address of the ATEX Auditing Organization: Baseefa Ltd., Rockhead Business Park, Staden Lane, Buxton, Derbyshire, SK17 9RZ.
The Marking of the equipment or protective system shall include the following: II 1G Ex ia IIC T4 Ga
Year to begin affixing CE Marking: 2016
Place: Tokyo, Japan
Date: Mar 31, 2016
Signature: Tetsuya Kawabe
Full Name: Tetsuya Kawabe
Title: Director, Quality control center
