Riken Keiki GD-F4A-SC-A User manual

Oxygen Gas Detector Head
GD-F4A-SC-A
Operating Manual
(PT2-152)
PT2E-2510

[OPERATING PRECAUTIONS]
This is a fixed type gas detector (head) and alarm instrument to detect oxygen gas in air. The
gas alarm instrument is a safety instrument, not an analyzer nor measuring instrument to make
quantitative and qualitative analysis or measurement.
Please understand following points and use this detector head correctly.
1. The indication on this detector has some changes against fluctuation of atmospheric
pressure. Especially, take care about alarm action at the time of depression caused by
typhoon.
It may also fluctuate against the environmental (temperature, humidity, etc.) change around
detector head.
2. Alarm level for gas alarm instrument shall be set within the performance of the instrument.
Our standard alarm level is 18% by volume for the prevention of oxygen deficiency.
3. This is not control equipment, but a safety instrument.
Use the alarm contact from gas alarm instrument only for external alarm light or buzzer.
And the analog output signal shall be used only for external indicator or recorder.
We do not assume liability for any accident or damage caused by other control purpose than
the above.
4. To maintain the performance of this gas detector, the regular maintenance service including
the regular parts replacement and adjustment described in this manual shall be required.
Also every 6 months regular maintenance and gas calibration are required since this is a
safety instrument.

TABLE OF CONTENTS
１．OUTLINE OF THE PRODUCT
１－１． Preface ………………………………………………………………………… 1
１－２． Purpose of use ………………………………………………………………… 1
１－３． Definition of DANGER, WARNING, CAUTION and NOTE…………………… 1
２．IMPORTANT INSTRUCTIONS FOR THE SAFETY
２－１． Danger cases…………………………………………………………………… 2
２－２． Warning cases…………………………………………………………………… 2
２－３． Caution cases…………………………………………………………………… 2
２－４． Caution for explosion proof (In case of intrinsically safe design)…………… 2
３．PRODUCT COMPONENTS
３－１． External drawing………………………………………………………………… 3
３－２． Name of each part and functions……………………………………………… 4
３－３． System composition …………………………………………………………… 4
４．HOW TO USE
４－１． Before using the detector head………………………………………………… 7
４－２． Precautions for installation points……………………………………………… 7
４－３． Maintenance space……………………………………………………………… 7
４－４． How to install …………………………………………………………………… 8
４－５． Caution at wiring construction…………………………………………………… 8
４－６． Applicable cable………………………………………………………………… 8
４－７． Example of cable connection…………………………………………………… 8
４－８． Caution at piping works…………………………………………………………… 10
４－９． Example of piping connection…………………………………………………… 10
５．HOW TO OPERATE
５－１． Preparation for start up………………………………………………………… 12
５－２． How to start the detector head………………………………………………… 12
５－３． How to exit……………………………………………………………………… 12
６．MAINTENANCE
６－１． Maintenance intervals and items………………………………………………… 13
６－２． 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 intervals of the sensor ………………………………… 15
６－３－２． How to replace the sensor……………………………………………… 16
６－４． Storage or treatment when not in use for a long period………………………… 17
６－５． List of recommendable spare parts for regular replacement…………………… 17
７．STORAGE, RELOCATION AND DISPOSAL
７－１． Procedures to storage the detector head or leave it for a long time …… 18
７－２． Procedures to relocate the detector head or use it again ………………… 18
７－３． Disposal of products ………………………………………………………… 18
８．MEASURES AT ABNORMAL CASE
８－１． Responding to trouble alarm ……………………………………………… 19
８－２． Before it is thought to be a trouble………………………………………… 19
９．PRODUCT SPECIFICATIONS
９－１． Standard specifications ………………………………………………… 20
９－２． Standard accessories ……………………………………………………
20
９－３． Optional accessories …………………………………………………… 20
９－４． Detection principle ……………………………………………………… 21
１０．DEFINITION OF TERMS………………………………………………… 22

1
１．OUTLINE OF THE PRODUCT
１－１．Preface
Thank you for purchasing our fixed type Oxygen Detector Head GD-F4A-SC-A.
First of all, verify that the model number of this product is identical with specifications
described in this manual. This manual is a guide to operation of the GD-F4A-SC-A. All
parsons who use this unit for the first time and who has ever used this unit are requested to
read through the manual to understand the content before use.
１－２．Purpose of use
This is a suction(flow-through) 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 operating 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.
DANGER
WARNING
CAUTION
* NOTE

2
２. IMPORTANT INSTRUCTIONS FOR THE SAFETY
２－１．Danger cases
２－２．Warning cases
２－３．Caution cases
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 away 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.
CAUTION
DANGER

4
３－２．Name of each part and functions
① Oxygen sensor : Galvanic type sensor to detect oxygen content.
② Sensor holder : This is a retainer to hold the oxygen sensor
(equipped filter inside).
③ Sensor lead wires : Lead wires for oxygen signal outputs.
④ Terminal strip 1 : Relayed terminal for sensor lead wires 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 Terminal strip 2 : Relayed terminal for input/output signal use to the signal converter.
⑩ 4mA adjusting hole : VR hole to adjust 4 mA of 4-20mA output(factory set)
⑪ SPAN adjusting hole : VR hole to adjust SPAN
⑫ ZERO adjusting hole : VR hole to adjust ZERO
⑬ Front door : Front door for the unit
⑭ Signal converter : Circuit unit to convert the sensor output into 4-20mA
⑮ Protective earth bolt : Bolt for protective grounding.
３－３．
System composition
(1) Intrinsically safe system
Detector
head
Zener barrier
Indicator
/alarm
unit
Hazardous area Non-hazardous area
In-between head and zener barrier :
CVVS 1.25mm2 2-core or equivalent (max 250m)
However, that of head and indicator/alarm unit :
CVVS 1.25mm2 2-core or equivalent (max 2km)
４－２０ｍＡ
①
②
③
④
⑤
⑥
⑦
⑧
⑨
⑩
⑪ ⑫
⑬
⑭
⑮

5
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 93 mA
Max power of intrinsic- safety circuit: Below 0.65W
(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
3. 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
！
Hazardous
area
Non-hazardous
area
Safety retainer
Oxygen detector
Ｌｉ≒ 0
Ｃｉ≒ 0
≒ 0 shows a negligible value
Ｌｉ
Ｃｉ
Ｌｏ
Ｃｏ
Ｌｗ
Ｃｗ

6
(2) Non-explosion proof system
(3) Component inside detector head
Detector
head
Indicator/alarm unit
Non-hazardous area Non-hazardous area
CVVS 1.25mm2 2-core
or equivalent (MAX 2km)
4-20mA
Signal converter
Sensor lead wire
Terminal
4-20mA
Cable
Cable gland
O2
senso
r
Gas inlet
Gas outlet

7
4．HOW TO USE
４－１．Before using the detector head
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．Precautions for installation points
When installing this detector, 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.
WARNING