Riken Keiki SD-2500 User manual

PT2E-15913
Furnace Gas Monitor
SD-2500
Operating Manual
(PT2E-159)
(PT2-159)

SD-2500
Operating Precautions
This gas monitor is a gas detector that detects combustible gases in the air and triggers a gas alarm.
The gas detector is a safety unit, not an analyzer or densitometer which performs quantitative/qualitative
analysis/measurement for gases.
Please fully understand the following points before using it, so that it can be used properly.
1. This gas monitor may be interfered by gases and vapors other than the gas to be detected.
Please note that the alarm may be triggered by interference. 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 gas monitor can be ensured.
In facilities compliant with the High Pressure Gas Safety Act, an alarm setting below our standard alarm
setpoint may trigger a false alarm.
3. This is a safety unit, not a control unit.
The alarm contact output of the gas monitor must be used for an external alarm lamp/buzzer, while the
analog signal output must be used for an indicator or external recorder. If these outputs are used to
control other units, we shall not be responsible for any malfunctions.
4. The gas sensing part of the gas detection sensor installed in this gas monitor is made of metal porous
sintered alloy permeated with an oxidation catalyst.
If silicon or sulfide compounds are accumulated on the surface of porous sintered alloy, the area of the
gas sensing part becomes smaller, which may results in serious deterioration of its sensitivity.
For safety reasons, do not use the gas monitor under the presence of silicon or sulfide compounds
even though their amount is very small.
5. For maintenance of the gas monitor, 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 a gas calibration are
performed every six months in accordance with the regulations.

<Contents>
1 Outline of the Product.............................................................................................. 1
1-1. Preface .................................................................................................................... 1
1-2. Purpose of use ........................................................................................................ 1
1-3. Definition of DANGER, WARNING, CAUTION, and NOTE ..................................... 1
1-4. Method of confirmation for Standards and Explosion proof specification.................
2 Important Notices on Safety .................................................................................... 3
2-1. Danger cases .......................................................................................................... 3
2-2. Warning cases......................................................................................................... 3
2-3. Precautions ............................................................................................................. 4
2-4. Safety Information ................................................................................................... 4
3 Product Components............................................................................................... 6
3-1. Main unit and standard accessories ........................................................................ 6
3-2. Names and functions for each part.......................................................................... 7
3-3. Block diagram.......................................................................................................... 8
4 How to Use.............................................................................................................. 9
4-1. Before using the gas monitor................................................................................... 9
4-2. Precautions for installation points............................................................................ 9
4-3. Precautions for system designing............................................................................ 10
4-4. How to install ........................................................................................................... 13
4-5. How to wire.............................................................................................................. 14
5 How to Operate ....................................................................................................... 19
5-1. Preparation for start-up............................................................................................ 19
5-2. Basic operating procedures..................................................................................... 19
5-3. How to start the gas monitor.................................................................................... 20
5-4. Modes...................................................................................................................... 21
5-5. User mode............................................................................................................... 22
5-6. How to exit............................................................................................................... 24
6 Operations and Functions ....................................................................................... 25
6-1. Gas alarm activation................................................................................................ 25
6-2. Fault alarm activation .............................................................................................. 26
6-3. External output operation ........................................................................................ 27
6-4. Other functions ........................................................................................................ 28
7 Maintenance............................................................................................................ 29
7-1. Maintenance intervals and items ............................................................................. 29
7-2. Regular maintenance mode .................................................................................... 31
7-3. Gas calibration method............................................................................................ 38
7-4. Parts replacement ................................................................................................... 40
8 Storage, Relocation and Disposal ........................................................................... 41
8-1. Procedures to store the gas monitor or leave it for a long time............................. 41
8-2. Procedures to relocate the gas monitor or use it again ........................................... 41
8-3. Disposal of products................................................................................................ 41
9 Troubleshooting....................................................................................................... 42
10 Product Specifications ............................................................................................. 44
10-1. List of specifications ................................................................................................ 44
10-2. List of accessories................................................................................................... 47
10-3. Detection principle................................................................................................... 48
11 Definition of Terms................................................................................................... 49
2

1 Outline of the Product 1-1. Preface
SD-2500 - 1 -
1
Outline of the Product
1-1. Preface
Thank you for choosing our furnace gas monitor SD-2500. 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 monitor and its specifications. It contains information required for
using the gas monitor 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 monitor.
1-2. Purpose of use
The gas monitor is a fixed type detector head that continuously detects combustible gases and that
performs the alarm activation when the gas concentration is over the setting value.
This gas monitor is a safety unit, not an analyzer or densitometer which performs quantitative/qualitative
analysis/measurement for gases. Please fully understand the features of the gas monitor before using it, so
that it can be used properly.
The gas monitor detects abnormalities in the air caused by presence of gases or other reasons (leak) with
the built-in gas sensor. The concentrations of detected gases are displayed on the seven-segment LED.
The gas monitor has a built-in alarm contact and can be used either as a gas alarm, fault alarm, or common
(gas, fault) alarm.
The gas monitor outputs gas concentration in 4 – 20 mA.
1-3. Definition of DANGER, WARNING, CAUTION, and
NOTE
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
- 3 - SD-2500
DANGER
<About explosion-proof>
The window plate material is a polycarbonate resin. Do not use organic solvents and alkali types
(liquid or vapor). It may cause the color and shape of the window plate to be changed.
Do not open the lid when applying current.
Do not attempt to repair the detector.
For the lid, use hexagon socket head bolts specified by RIKEN KEIKI.
Do not apply a strong force or shock to the window plate. The explosion-proof performances may be
deteriorated due to damages. The explosion protection conditions for the detector is "low (2J)"
possibility of mechanical damage.
Do not repair the explosion-proof joint surface.
2
Important Notices on
Safety
2-1. Danger cases
2-2. Warning cases
WARNING
Power supply
Before turning on the gas monitor, always check that the voltage is properly applied. Do not use an
unstable power supply because it may cause malfunctions.
Need of grounding circuit
Do not cut the grounding circuit or disconnect the wire from the grounding terminal.
Defects in protective functions
Before starting the gas monitor, check the protective functions for defects. When seeming defects are
found in the protective functions, such as protective grounding, do not start the gas monitor.
External connection
Before connecting the gas monitor to the external control circuit, securely connect it to a protective
grounding circuit.

2 Important Notices on Safety 2-3. Precautions
SD-2500 - 4 -
WARNING
Zero adjustment in the atmosphere
When the zero adjustment is performed in the atmosphere, check the atmosphere for freshness before
beginning the adjustment. If other gases exist, the adjustment cannot be performed properly, thus
leading to dangers when the gas leaks.
Response to a gas alarm
Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based on your
judgment.
2-3. Precautions
CAUTION
Do not use a transceiver near the gas monitor.
Radio wave from a transceiver near the gas monitor or its cables may disturb indication reading. If a
transceiver is used, it must be used in a place where it disturbs nothing.
To restart the gas monitor, wait for five seconds or more before doing it.
Restarting the gas monitor within five seconds may cause errors.
Do not use the external output of the gas monitor to control other units.
This is not a control unit. It is not allowed to use the external output of the gas monitor to control other
units.
Do not disassemble/modify the gas monitor, or change the settings if not necessary.
Disassembling/Modifying the gas monitor will invalidate the warranty of the performance. Changing the
settings without understanding the specifications may cause alarm malfunctions. Please use the gas
monitor properly in accordance with the operating manual.
Avoid applying organic solvents and others to the window plate for a long time.
The window plate material is a polycarbonate resin. When organic solvents (liquid or highly-concentrated
vapor) and others are applied to the plate for a long time, its color and shape may be changed.
The zero adjustment in the furnace
After the furnace becomes the operating temperature, perform the zero adjustment carry out after one
hour.
Do not forget to perform a regular maintenance.
Since this is a safety unit, a regular maintenance must be performed to ensure safety. Continuing to use
the gas monitor without performing a maintenance will deteriorate the sensitivity of the sensor, thus
resulting in inaccurate gas detection.

3 Product Components 3-1. Main unit and standard accessories
SD-2500 - 6 -
3
Product Components
3-1. Main unit and standard accessories
<Main Unit> (including a cable gland)
<Standard Accessories>
Operating manual
Dedicated handling lever (used for the wiring)
Dedicated control key
Flange gasket
Exhaust air direction nameplate
CAUTION
Use the supplied dedicated control key to operate the gas monitor. If products other than these
accessories are used, key operations cannot be accepted properly.

3 Product Components 3-3. Block diagram
SD-2500 - 8 -
3-3. Block diagram
<Electric Diagram>
Sensor
Controller
(CPU)
POWER INPUT (24 VDC)
Power supply part
Gas alarm contact (ALARM)
Contact activation
• De-energized
(De-energized at a
normal environment)
• ON-ALARM
(Closed contact at an
alarm time)
Alarm contact controller
Display
(POWER) (ALARM) (FAULT)
Seven-segment LED
(four-digit)
Magnetic operation part
(MENU/ESC) (▲) (▼) (SET)
Transmitter
• 4 – 20 mA transmission

4 How to Use 4-1. Before using the gas monitor
- 9 - SD-2500
4
How to Use
4-1. Before using the gas monitor
Not only the first-time users but also the users who have already used the product must follow the operating
precautions.
Ignoring the precautions may damage the gas monitor, resulting in inaccurate gas detection.
4-2. Precautions for installation points
Do not install the gas monitor in a place with vibrations or shocks.
The gas monitor consists of sensitive electronic parts. The gas monitor must be installed in a stable place
without vibrations or shocks and it cannot drop.
Do not install the gas monitor in a place exposed to water, oil or chemicals.
When selecting installation points, avoid a place where the gas monitor is exposed to water, oil or
chemicals.
Install the gas monitor in a place with operating environment temperatures that meet the following
requirements:
<ATEX/IECEx Specifications>
Main unit case part:
The detector head must be installed in a stable place where the operating temperature is 0 to +50C and
do not change suddenly.
Gas sensor part: 0 to +160C
<TIIS Specifications>
Main unit case part:
The detector head must be installed in a stable place where the operating temperature is -20 to +60C
and do not change suddenly.
Gas sensor part: 0 to +160C
CAUTION
This is a precision device. Because the gas monitor may not provide the specified performance in some
places (environments), check the environment in the installation point, and then take appropriate actions
if necessary.
Because the gas monitor plays an important role for safety and disaster prevention, as many units of the
gas monitor as needed must be installed in appropriate points.
Because points where gases leak and remain easily are different depending on the types of gases and
the working areas, please decide carefully on installation points and the number of units to be installed.

4 How to Use 4-3. Precautions for system designing
SD-2500 - 10 -
Do not install the gas monitor in a place exposed to direct sunlight or sudden changes in the temperature.
When selecting installation points, avoid a place where it is exposed to direct sunlight or radiant heat
(infrared rays emitted from a high-temperature object), and where the temperature changes suddenly.
Condensation may be formed inside the gas monitor, or the gas monitor cannot adjust to sudden changes
in the temperature.
Keep the gas monitor (and its cables) away from noise source devices.
When selecting installation points, avoid a place where high-frequency/high-voltage devices exist.
Do not install the gas monitor in a place where maintenance of the gas monitor cannot be performed or
where handling the gas monitor involves dangers.
Regular maintenance of the gas monitor must be performed.
Do not install the gas monitor in a place where the machinery must be stopped when maintenance is
performed in its inside, where parts of the machinery must be removed to perform maintenance, or where
the gas monitor cannot be removed because tubes or racks prevent access to it. Do not install the gas
monitor in a place where maintenance involves dangers, for example, near a high-voltage cable.
Do not install the gas monitor in machinery which is not properly grounded.
Before installing the gas monitor in machinery, the machinery must be grounded properly.
Do not install the gas monitor in a place where other gases exist around it.
The gas monitor must not be installed in a place where other gases exist around it.
4-3. Precautions for system designing
Using a stable power supply
The external output and alarm contact of the gas monitor may be activated when the power is turned on,
when momentary blackout occurs, or when the system is being stabilized. In such cases, use a UPS, or
take appropriate actions on the receiving side of output signals.
The gas monitor must be provided with the following power supply.
Power supply
voltage 24 VDC±10%: Terminal voltage of the gas monitor
Allowed time of
momentary blackout
Up to 10 milliseconds
(To recover from the momentary
blackout for 10 milliseconds or more,
restart the gas monitor.)
Example of actions
To ensure continuous operation and
activation, install a UPS outside the
gas monitor.
Others
Do not use it with a power supply of
large power load or high-frequency
noise.
Example of actions
Use a line filter to avoid the noise
source if necessary.
Introducing protective measures against lightning
If cables are installed outside the factory/plant, or if internal cables are installed in the same duct as the cables
coming from outside the factory/plant, "lightning" will cause problems. Because lightning acts as a large emission
source while cables act as a receiving antenna, devices connected to the cables may be damaged.
Lightning cannot be prevented. Cables installed in a metal conduit or under the ground cannot be
completely protected from inductive lightning surge caused by lightning. Although complete elimination of
disasters caused by lightning is impossible, the following protective measures can be taken.
Protection against
lightning
Take appropriate measures in accordance with the importance of the facilities
and the environment.
Provide protection by a lightning arrester (cable arrester).
(Although inductive lightning surge can be transmitted through the cable, it is
CAUTION
An unstable power supply and noise may cause malfunctions or false alarms.
The descriptions in this section must be reflected on the designing of a system using the gas monitor.

4 How to Use 4-3. Precautions for system designing
- 11 - SD-2500
prevented by installing a lightning arrester before the field devices and central
processing equipment. For information on how to use a lightning arrester,
please contact the manufacturer.)
Grounding In addition to lightning, there are more sources of surge noise. To protect units
from these noise sources, the units must be grounded.
* The lightning arrester has a circuit to remove a surge voltage which damages field devices, so that signals
may be attenuated. Before installing a lightning arrester, verify that it works properly.
Proper use of alarm contact
The alarm contact of the gas monitor is used to transmit signals to activate an external buzzer, an alarm
lamp or a rotating lamp. Do not use the gas monitor for controlling purpose (e.g., controlling the shutdown
valve.)
The specifications for the alarm contact of the gas monitor are based on the resistant load conditions. If
inductive load is used at the alarm contact, the following errors will occur easily because counter
electromotive force is generated at the contact.
Deposition, defective insulation or defective contact at the relay contact
Damage of any electric parts due to high-voltage generated inside the gas monitor
Abnormal operations by an out-of-control CPU
If load is to be activated, appropriate measures must be taken to stabilize the operation of the gas monitor
and protect the alarm contact referring to the following information.
Relay it with an external relay at a lower voltage of 100 VAC or below (contact amplification). At the same
time, the surge absorbing part SK1 suitable for the specifications must be attached to the external relay.
In addition, the surge absorbing part SK2 must be attached to the loaded side of the external relay if
necessary.
It may be recommended that the surge absorbing part should be attached to the contact for certain load
conditions. It must be attached to an appropriate position by checking how the load is activated.
CAUTION
In principle, do not activate inductive load at the alarm contact of the gas monitor. (In particular, never
use the inductive load to activate a fluorescent lamp or motor.)
If inductive load is activated, relay it with an external relay (contact amplification). However, because
the coil of an external relay also involves inductive load, select a relay at a lower voltage (100 VAC or
below), and then protect the contact of the gas monitor with an appropriate surge absorbing part, such
as a CR circuit.
CAUTION
The b contact (break contact) under de-energized state may be opened momentarily by a physical
shock, such as external force.
When the b contact is selected for the alarm contact, take appropriate actions to prepare for a
momentary activation, for example, add signal delay operation (approximately one second) to the
receiving side of the b contact.

4 How to Use 4-5. How to wire
SD-2500 - 14 -
4-5. How to wire
<Recommended Cable>
3-wire (when the contact is not used) CVVS1.25 mm2- 3-core
5-wire (when the contact is used) CVVS1.25 mm2- 5-core
<Parts. length table of outside conductor lead-in>
The parts for the external cable inlet are different from specifications. Use the appropriate parts, referring
to the following lists.
ATEX/IECEx Specifications
Cable overall outer
diameter(mm)
Rubber seal inner
diameter(mm)
Washer inner
diameter(mm)
Clamp inner
diameter(mm)
From Φ9.6 to less than Φ10.5 Φ11 Φ12 Φ10.8
From Φ10.5 to less than Φ11.5 Φ12 Φ12 Φ11.8
From Φ11.5 to less than Φ12.5 Φ13 Φ14 Φ12.8
From Φ12.5 to less than Φ13.0 Φ13.5 Φ14 Φ13.8
TIIS Specifications
Cable overall outer
diameter(mm)
Rubber seal inner
diameter(mm)
Washer inner
diameter(mm)
From Φ9.6 to less than Φ11.0 Φ11 Φ12
From Φ11.0 to less than Φ11.5 Φ12 Φ12
From Φ11.5 to less than Φ12.0 Φ12 Φ14
From Φ12.0 to less than Φ13.0 Φ13 Φ14
Φ13.0 Φ13.5 Φ14
CAUTION
Be careful not to damage the internal electronic circuit when wiring. In addition, be careful not to apply
stresses on the gas monitor when (overweight) cables are installed.
The power cables and signal cables must not be installed together with the motor power cables, etc.
When these cables must be installed together for unavoidable reasons, put the power cables and
signal cables in a metal conduit. The conduit must be connected to a grounding circuit.
When stranded wires are used, prevent wires from contacting each other.
Use the dedicated handling lever to wire.