Riken Keiki GD-F4A-A User manual

PT2E-2501
Oxygen Gas Detector Head
GD-F4A-A
Operating Manual
(PT2-151)

Operating Precautions
This detector is an oxygen deficiency detector that detects oxygen in the air and triggers an oxygen
deficiency alarm.
The oxygen deficiency detector is a safety unit, not an analyzer or densitometer which performs
quantitative/qualitative analysis/measurement for oxygen.
Please fully understand the following points before using it, so that it can be used properly.
1. The readings of the detector fluctuate slightly in response to changes in the air pressure.
In particular, be careful of alarm activation when a low air pressure is brought in by typhoon. In
addition, it may be fluctuated by environmental (temperature, humidity etc.) changes in the
installation site.
2. The alarm must be set within a range where the performance of the detector can be ensured.
The standard alarm setpoint value is 18 vol%.
3. This is a safety unit, not a control unit.
The alarm contact output of the detector must be used for an external alarm lamp/buzzer, while the
analog signal output must be used for an indicator or external recorder.
4. For maintenance of the detector, it must go through a regular maintenance, including replacement
and adjustment of the regular replacement parts as specified in the operating manual. In addition,
because this is a safety unit, it is recommended that a regular maintenance and span adjustment are
performed every six months.

1
TABLE OF CONTENTS
１．PRODUCT OUTLINE
１－１． Preface ……………………………………………………………………… 2
１－２． Application for use …………………………………………………………… 2
１－３． Definition of DANGER, WARNING, CAUTION and NOTE ………………… 2
１－４． Method of confirmation for CE/UKCA marking type
(Non-explosion proof specification only) ………………… 2
２．IMPORTANT INSTRUCTIONS FOR THE SAFETY
２－１． Danger cases ………………………………………………………………… 3
２－２． Warning cases ………………………………………………………………… 3
２－３． Precaution …………………………………………………………………… 3
２－４． Caution for explosion proof (In case of intrinsically safe design) ………… 3
３．PRODUCT COMPONENTS
３－１． External dimensions ………………………………………………………… 4
３－２． Names and functions for each part ………………………………………… 5
３－３． System composition ………………………………………………………… 6
４．HOW TO USE
４－１． Before operation …………………………………………………………… 8
４－２． Installation place …………………………………………………………… 8
４－３． Maintenance space ………………………………………………………… 8
４－４． Installation work …………………………………………………………… 8
４－５． Caution at wiring construction …………………………………………… 9
４－６． Applicable cable …………………………………………………………… 9
４－７． Example of cable connection ……………………………………………… 9
４－８． Caution at piping works ……………………………………………………… 10
４－９． Example of piping connection ……………………………………………… 11
５．OPERATION METHOD
５－１． Preparation for start up …………………………………………………… 12
５－２． Start up ……………………………………………………………………… 12
５－３． Stopping the operation ……………………………………………………… 12
６．MAINTENANCE AND INSPECTION
６－１． Inspection frequency and items …………………………………………… 13
６－２． How to calibration
６－２－１． Required kit and tools for calibration …………………………… 14
６－２－２． Performing a zero adjustment …………………………………… 14
６－２－３． Performing a span adjustment …………………………………… 14
６－３． Replacing the sensor
６－３－１． Replacement frequency of the sensor ………………………… 15
６－３－２． How to replace the sensor ……………………………………… 15
６－４． List of recommendable spare parts for regular replacement …………… 16
７．STORAGE, RELOCATION AND DISPOSAL
７－１． Procedures to store the detector head or leave it for a long time ……… 17
７－２． Procedures to relocate the detector head or use it again ……………… 17
７－３． Disposal of products ……………………………………………………… 17
８．MEASURES AT ABNORMAL CASE
８－１． Responding to trouble alarm ……………………………………………… 18
８－２． Before it is thought to be a trouble ……………………………………… 18
９．PRODUCT SPECIFICATIONS
９－１． Standard specifications ………………………………………………… 19
９－２． Standard accessories …………………………………………………… 19
９－３． Optional accessories …………………………………………………… 19
９－４． Detection principle ………………………………………………………… 20
１０．DEFINITION OF TERMS …………………………………………………………… 21

2
１．PRODUCT OUTLINE
１－１．Preface
Thank you for choosing our fixed type Oxygen Detector Head GD-F4A-A. 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 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 detector.
１－２．Application for use
This is a suction type oxygen detector head applying the galvanic cell type oxygen sensor and is used in
combination with indicator / alarm unit to show oxygen content. Read the instruction manual for
indicator / alarm unit as well as this manual.
This unit is designed as drip-proof construction for outdoor installation.
Also, it can be used as intrinsically safe system in combination with zener barrier (option) to be able to
install in hazardous area.
１－３．Definition of DANGER, WARNING, CAUTION and NOTE
This manual contains the following headings to ensure the safe and effective operation.
This message indicates that improper handling may cause serious damage on
life, health or assets.
This message indicates that improper handling may cause serious damage
on health or assets.
This message indicates that improper handling may cause minor damage on
health or assets.
This message indicates advice on handling.
１－４．Method of confirmation for CE/UKCA marking type
(Non-explosion poof specification only)
The CE/UKCA marking is labeled on the detector in case of comply with CE/UKCA mark (Non-explosion
poof specification only). Please confirm the instrument specification before using. Please refer Declaration
of Conformity that is at the end of this manual if you have CE/UKCA marking type.
You can confirm instrument specification to see the CE/UKCA mark as follows.
DANGER
WARNING
CAUTION
* NOTE
CE/UKCA mark
CE/UKCA mark label
(Non-explosion poof specification only)

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２．IMPORTANT INSTRUCTIONS FOR THE SAFETY
２－１．Danger cases
２－２．Warning cases
２－３．Precaution
２－４．Caution for explosion proof (In case of intrinsically safe design)
In case of non-explosion poof system, do not use this unit at the place where combustible gas may exist.
・Do not cut the wire for protective ground both inside and outside of instrument. Or, do not disconnect the
connection of the ground terminals.
・Before starting the operation, check if any defect is not found on the protective grounding.
・If there is any defect on the protective functions such as protective grounding, do not start the operation.
・It is very dangerous if the instrument gives oxygen deficiency alarm.
Take appropriate measures based on your judgment at that time.
・Perform gas calibration at proper interval.
・Do not change or remodel the circuit/structure of this unit.
・Do not disassemble the sensor since there is a electrolyte inside.
If your finger touches the electrolyte, wash your finger way with water immediately.
WARNING
・Do not use a walky-talky around the instrument.
The indication might be affected by the electromagnetic wave generated by the walky-talky if it is used near
the instrument. When the walky-talky is used, be away enough from the instrument not to affect.
・Do not control other equipment by using outputs of this detector.
This is not a control equipment. It is prohibited to control other equipment by using outputs of this
detector.
CAUTION
・Do not use this detector head expect for the measurement of oxygen content in a mixture of air and
combustible gas or vapors, or a mixture of air and toxic gases.
・When cleaning this unit, do not use dry cloth but use the wet cloth not to change the static electricity on plastic
part.
DANGER
DANGER

4
３．PRODUCT COMPONENTS
３－１．External dimensions
Cable inlet
Cable inlet Sensor
Gas inlet
Protective
ground
Gas outlet
(For U-bolt)
Cable inlet Sensor
Gas inlet
Protective ground Gas outlet
(For U bolt)

5
３－２．Names and functions for each part
① Oxygen sensor : Galvanic type sensor to detect oxygen content.
② Sensor retainer : This is a retainer to hold the oxygen sensor
(equipped with filter inside).
③ Sensor lead : Lead wires for oxygen signal outputs.
④ Terminal strip : Relayed terminal for sensor lead and external cable.
⑤ Cable gland : Entrance to lead the cable (φ8～φ11mm) from outside.
⑥ Hinge : Hinge for front door.
⑦ Lock : Lock for front door.
⑧ Mounting hole : Mounting hole to fix this unit on the wall surface.
⑨ Protective earth bolt : Bolt for protective grounding.
⑥
⑨ ⑤
③
⑦
①
②
④ ⑧

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３－３．System composition
(1) Intrinsically safe system
１．The oxygen detector shall be used as following composition.
２．The safety retainer to be connected with oxygen detector shall have linear characteristics and be passed
the type approval as it is.
Also it shall satisfy the following conditions.
(1) Rating of safety retainer
Max voltage of intrinsic-safety circuit : Below 28V
Max current of intrinsic-safety circuit : Below 600 mA
Max power of intrinsic-safety circuit : Below 0.75W
(2) Performance division and group
Performance division : ia
Group : ⅡC
(3) Relations between allowable inductance (Lo) and allowable capacitance (Co)
of intrinsic-safety circuit, and external wiring inductance (Lw) and capacitance(Cw)
of intrinsic-safety circuit.
Lo ≧ Li + Lw
Co ≧ C + Cw
(4) When making wiring connection for intrinsic-safety circuit, take care not to induce an electric
current and voltage which will spoil the performance of intrinsically safe by the electromagnetic
induction or electrostatic induction to the intrinsic-safety circuit.
WARNING
！
Detector
head
Zener barrier
Indicator
/alarm
unit
Hazardous area Non-hazardous area
CVVS-2C 1.25mm2 or equivalent (max 600m) cable
Hazardous
area
Non-hazardous
area
Safety retainer
Oxygen detector
Ｌｉ≒ 0
Ｃｉ≒ 0
≒ 0 shows a negligible value
Ｌｉ
Ｃｉ
Ｌｏ
Ｃｏ
Ｌｗ
Ｃｗ

7
(2) Non-explosion proof system
(3) Component inside detector head
Drip-proof housing
Sensor lead
Terminal strip
Cable gland
Shielded cable
Oxygen
sensor
Gas inlet
Gas outlet
Detector
head
Indicator/alarm unit
Non-hazardous area Non-hazardous area
CVVS-2C 1.25mm2 or equivalent (MAX 600m)

8
４．HOW TO USE
４－１．Before operation
All persons who use this detector for the first time and who has even used the detector are requested to
follow all the instructions for use carefully. If not, the instrument may be defective and correct gas
detection may not be performed.
４－２．Installation place
This detector head is installed at the place of oxygen detection directly since this is a diffusion detector
head.
Note the following points.
Do not install the detector head and cable at the following points.
・Place to get direct rays of the sun.
・Places closed to high temperature and/or emission of electromagnetic wave.
・Place with vibration or shocks.
・Place where the mounting part is weak and it is easy to come out.
・Place where it is difficult to make maintenance and inspection.
・Place unable to secure grounding.
・Places where the temperature is drastically changed.
・Places exceeding operating temperature and humidity.
４－３．Maintenance space
A certain maintenance space must be secured around the detector head, so that the maintenance staff can
perform the safe and correct maintenance work. Pay due attention to secure this space during work plan
and execution.
４－４．Installation work
(1) Mounting to the wall surface
Mount the detector head to a flat surface (wall surface, etc)
with either M6 bolts or M10 bolts through mounting holes.
Refer to”3-1. External dimensions” for mounting pitch.
(2) Mounting to the pole
The unit can be mounted to the pole (2B pipe)
by using the optional U-bolts as show right figure.
(3) Installation to the outdoors
For outdoor installation, optional drip-proof cover is required
to keep reliable detection although this is a drip-proof design.
Contact authorized distributors, dealers or representative
appointed by RIKEN KEIKI Co., Ltd.
WARNING
Mounting to the pole
2B pipe
（O.D. 60.5mm）
U-bolt
（Nominal
diameter 50B）