Oldham BM25 User manual

BM25
O
OP PE ER RA AT TI IN NG G M MA AN NU UA AL L
REF:
NPB25GB
REV E

3
GAS DETECTION
We are delighted that you have chosen an INDUSTRIAL SCIENTIFIC-instrument and would like to
thank you for your choice.
We have taken all the necessary measures to ensure that your instrument provides totalsatisfaction.
Now it is important to read this document carefully.
E
EX XT TE EN NT T O OF F R RE ES SP PO ON NS SI IB BI IL LI IT TY Y
*INDUSTRIAL SCIENTIFIC-declines its responsibility towards any person for material damage, physical injury
or death resulting wholly or partly from inappropriate use, installation or storage of its equipment resulting from
failure to observe instructions and warnings and/or standards and regulations in force.
*INDUSTRIAL SCIENTIFIC-neither supports nor authorises any company, physical or moral person to assume
responsibility on behalf of INDUSTRIAL SCIENTIFIC-, even if it is involved in the sale of INDUSTRIAL
SCIENTIFIC-products.
*ISC/ cannot be held responsible for direct or indirect damage or be required to pay direct or indirect compensation
resulting from the sale or use of any of its productsIF THESE PRODUCTS HAVE NOT BEEN DEFINED AND
CHOSEN BY INDUSTRIAL SCIENTIFIC-FOR THEIR SPECIFIC USE.
C
CL LA AU US SE ES S C CO ON NC CE ER RN NI IN NG G P PR RO OP PE ER RT TY Y
*Drawings, plans, specifications and information included in this document contain confidential information that is
the property of INDUSTRIAL SCIENTIFIC-
*None of this information may be reproduced, copied, divulged or translated, by physical, electronic or any other
means, nor used as the basis for the manufacture or sale of INDUSTRIAL SCIENTIFIC-equipment or for any
other reasons without prior consent from INDUSTRIAL SCIENTIFIC-
W
WA AR RN NI IN NG GS S
*This document is not contractually binding. In the interests of its customers, INDUSTRIAL SCIENTIFIC-
reserves to modify the technical specifications of its equipment without notice, in order to improve its performance.
*READ THIS MANUAL CAREFULLY BEFORE FIRST USE OF THE EQUIPMENT: this manual must be
read by any person who is or will be responsible for using, maintaining or repairing this equipment.
*This equipment will only provide the announced performance levels if it is used, maintained and repaired
according to INDUSTRIAL SCIENTIFIC-directives, by INDUSTRIAL SCIENTIFIC-personnel or by
personnel approved by INDUSTRIAL SCIENTIFIC-
G
GU UA AR RA AN NT TE EE E
2 years guarantee in normal conditions of use on parts and technical labour, return in our workshops, excluding
consumables (sensors, filters, etc.)

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CONTENTS
I. INTRODUCTION...........................................................6
1. POWER ...........................................................................................................................6
1.1. Power supply...............................................................................................................................................................................................................................................................................................................................................................................................................................................6
1.1.1. Charging the battery pack.............................................................................................................6
1.1.2. Trickle charge.................................................................................................................................6
1.2. Memory saving ......................................................................................................6
2. SENSORS........................................................................................................................7
2.1. Connecting the sensors configuration samples ......................................................7
2.2. Explosive, toxic gas and oxygen metering sensors................................................8
3. DISPLAY UNIT..............................................................................................................8
4. VISUAL INDICATIONS................................................................................................8
5. AUDIBLE ALARMS......................................................................................................8
6. SAMPLING.....................................................................................................................8
6.1. Operating instructions............................................................................................9
6.2. Electrical pumping system.....................................................................................9
6.3. Manual pumping system for manual and electrical pump .....................................9
6.4. Different probes .....................................................................................................9
6.5. Gas detector mode..................................................................................................9
7. Communication Software COM 2100...........................................................................10
II. UTILIZATION............................................................ 10
1. KEYBOARD.................................................................................................................10
2. READING MEASUREMENTS ...................................................................................10
3. STARTING UP .............................................................................................................11
3.1. Starting up in standard mode ...............................................................................12
3.2. Starting up with choice of reference explosive gas..............................................12
3.3. Start-up test and calibration due...........................................................................12
4. SHUTTING DOWN......................................................................................................13
5. DISPLAY BACKLIGHTING.......................................................................................13
6. SCROLLING THROUGH SET PARAMETERS.........................................................13
6.1. “Roundsman” function.........................................................................................13
6.2. Re-initialization of MIN/MAX ............................................................................14
7. ALARMS ......................................................................................................................14
7.1. “Gas” alarms ........................................................................................................14
7.2. Fault alarms..........................................................................................................14
7.3. Acknowledging gas alarms ..................................................................................15
7.3.1. Manually acknowledging gas alarms........................................................................................15
7.3.2. Acknowledging alarms automatically ......................................................................................15
7.4. Alarm transfer......................................................................................................16

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8. MEASUREMENTS ......................................................................................................16
8.1. Display of instantaneous readings .......................................................................17
8.1.1. Diffusion mode.............................................................................................................................17
8.1.2. With electric pump systems .......................................................................................................17
8.1.3. With manual pump systems .......................................................................................................17
8.2. Automatic range change « 0-100 % Gas »...........................................................17
8.3. Memorizing histogram measurements.................................................................18
8.3.1. Operating principle, memorized items:....................................................................................18
8.3.2. Memory capacity..........................................................................................................................18
8.3.3. Data storage time..........................................................................................................................18
III. SPECIAL INSTRUCTIONS FOR USE IN EXPLOSIVE
ATMOSPHERES OR HAZARDOUS LOCATIONS................ 18
1. Hazardous areas and general rules ................................................................................19
2. ATEX areas: input/output parameters ...........................................................................19
2.1. Gas detector recharge connector..........................................................................20
2.2. Connector for alarm outputs / fault and digital TOR inputs ................................20
2.3. External power connector for maintenance of the battery pack...........................20
2.4. Connector accessories / options ...........................................................................20
2.5. Reference for electrical signals of connectors .....................................................20
3. Marking .........................................................................................................................24
IV. MAINTENANCE.......................................................... 24
1. ACCESS TO MAINTENANCE MENUS ....................................................................25
1.1. Channel programming menu................................................................................25
1.2. Sensor calibration menu.......................................................................................27
1.3. Auto-zero menu....................................................................................................27
1.4. Date and time management menu........................................................................27
1.5. Exit menu.............................................................................................................27
V. COM 2100 SOFTWARE................................................. 27
Instrument connection..........................................................................................................28
Maintenance:........................................................................................................................28
VI. CHARGERS................................................................ 35
1. INTRODUCTION.........................................................................................................35
2. CHARGING THE BATTERY......................................................................................36
3. TRICKLE CHARGE.....................................................................................................36
VII. DISPOSAL.................................................................37
VIII. ACCESSORIES ........................................................... 37
IX. SPARE PARTS............................................................ 38
X. TECHNICAL CHARACTERISTICS .................................39
1. DESCRIPTION.............................................................................................................39
2. Sensors (non-exhaustive list).........................................................................................41

6
I
I. . I IN NT TR RO OD DU UC CT TI IO ON N
•The BM25 gas detector is a stand-alone gas detector that can be used in explosive gas
atmospheres according to directive ATEX 94/9/EC, the Canadian Electrical Code, and
international standard IEC 60079-10-1. It provides simultaneous detection of up to 5 gases
present in the air by means of sensors specific to each risk to be evaluated (under-oxygenation,
explosive or toxic gases).
1
1. . POWER
1.1. Power supply
The BM25 is powered by an interchangeable and rechargeable battery pack.
Under normal operating conditions, and depending on the sensor configuration, operating runtime
varies between a minimum of 75 hours and a maximum of 170 hours (100 hours standard).
The power supply unit is a NimH 7V2 / 9AH battery pack.
1.1.1. Charging the battery pack
A lateral connector allows the battery pack (see the section on CHARGERS) to be charged without
dismantling.
1.1.2. Trickle charge
You can trickle charge your BM25 continuously in a classified area to keep the charge level
constant (except in alarm conditions) for as long as needed by means of an intrinsically safe power
supply.
1.2. Memory saving
A lithium battery (non rechargeable) ensures the storage of the BM25 gas detector's specific data
(time/history), especially when the instrument is out of service (off mode) or without the battery
pack (main power supply).
This lithium battery has a maximum service life of two years without the main power supply
(battery discharged or internal switch in “off” position).
IMPORTANT: The instrument is approved for explosive atmosphere operations, only when
it is equipped with batteries of a type recommended by the manufacturer.
Switch instrument to “off” before any maintenance operation, such as:
battery replacement.

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2
2. . SENSORS
2.1. Connecting the sensors configuration samples
Notes: -“Big sensors” are “3 or 7 series” format. Example: Compensated butane or hydrogen CO
sensor
-In case sensors are present in slots 1bis and 1, the sensor for slot 1bis has priority and
deactivates the one for slot 1.
-The “combo” CO/H2S sensor can only be plugged in location no. 4.
Caution: Sensors’ slots and protection filters must be kept clean, or else measurements could
be affected.
1:
tox/Ox mini
2: tox/Ox mini
3/4: tox/Ox medium
1bis: Big sensor (7/3 series type or big
size) or medium
5. Explo LEL
Medium format sensors
-oxygen with 2 years service life
-CO/H2S, SO2, ETO etc…
-CO2 IR
Sensors S7/S3
-SO2, ETO etc…
-CO2 IR
Or medium oxygen sensor
with 2 years lifetime
Small format sensors
for toxic gases and
oxygen with 1 year
service life
5 1
2
3/4
1bis
Explosive gas sensor 0 to 100% LEL
or catharometric sensor 0to100 Vol.%

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2.2. Explosive, toxic gas and oxygen metering sensors
The removable, interchangeable and intelligent sensor blocks are made of catalytic, electrochemical
or IR sensor and electronic components, including an “EEPROM” memory in which INDUSTRIAL
SCIENTIFIC-has stored the sensor's specific characteristics (measuring range, various correction
coefficients, STEL and TWA alarms, date of manufacture, serial number, etc.).
Another parameter called the "wear rate" is used by the BM25 to automatically determine the
optimal time to replace the sensor.
These sensor blocks, also called “intelligent blocks,” are plugged in as indicated in Chapter 2.1.
Caution: Silicon vapors or other “poisons” may have an adverse effect on explosive gas
detection sensors and distort measurements (under-estimated measurements).
If the instrument is used in poisoned atmospheres, calibrate it before its next use.
3
3. . DISPLAY UNIT
This is an LCD type display unit which lights up automatically in backlit mode in alarm or fault
conditions and the display can be reversed.
It shows:
-five measurements for units, type of gas and the presence of a catharometer.
-a calibration reminder
-the date and time
-minimums-maximums
-the mean STEL and TWA values
-the remaining battery time (bar graph)
-operator identification (roundsman function)
-maintenance menus
-alarm transfers
4
4. . VISUAL INDICATIONS
An indicator light (made of 20 ultra-bright LEDs) installed on top of the instrument indicates alarm
conditions and can be seen from all directions.
5
5. . AUDIBLE ALARMS
The operator is also warned when an alarm is triggered by two very powerful, built-in horns (103
dB @ 1m).
6
6. . SAMPLING
The BM25 gas detector can be equipped with an internal electrical pump or an external manual
pump to measure gas concentrations in inaccessible locations or in locations needing to be verified
before access.

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6.1. Operating instructions
The operator can:
•Gas detector mode: place the gas detector in the working area and let the BM25
monitor the atmosphere.
•Sampling mode: take regular measurements by means of a sampling system (manual
or electrical).
6.2. Electrical pumping system
The BM25 gas detector can be optionally equipped with an integrated electrical pump, powered
directly from the gas detector’s battery pack.
Pump drainage is between 18 and 25 1/h
NOTE: After each use of the electrical pump, check the watertightness by obstructing the end of
the sampling line until the draining alarm is triggered.
6.3. Manual pumping systemfor manual and electrical pump
It consists of a cover, a horn bulb, a probe and a connecting line.
6.4. Different probes
Manual or electrical sampling systems can be equipped with various probes.
-Rigid probe
-Semi-rigid probe
-Telescopic probe
CAUTION: Flexible probes, horn bulbs and certain rods are not antistatic. The operator
must take the necessary precautions to avoid electrostatic discharges, and, in any event, must
prevent any hazardous discharge through a metallic probe.
6.5. Gas detector mode
The BM25 must be positioned vertically.
Depending on the type of gas to be detected or likely to be present, the instrument must be placed:
•On the ground for detection of heavy gasses (density > 1)
•At medium height (approx. 1 m.) or in an outlet nozzle for a general detection of a
maximum of gases or for oxygen monitoring.
•Optionally, the gas detector can also be used on a tripod to be more visible from
different areas.

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7
7. . Communication Software COM 2100
This password-protected software is used to supervise and maintain the BM25 gas detector:
-clearly displays readings and parameters on channels
-gives diagnostic assistance in case of failure
-helps programming of the instrument and sensor channels
-allows management of options
-enables calibration of channels through an automated scrolling menu
-prints status and monitoring reports
-enables the management, display and printout of events and measurements stored
The BM25 can be connected to a computer via a cable equipped with an infrared port.
Two versions are available:
-COM or USB port
I
II I. . U UT TI IL LI IZ ZA AT TI IO ON N
1
1. . KEYBOARD
Push buttons are "piezo" type with slight deformation.
They enable:
•turning the instrument on and off
•the display mode
•the acknowledgment of audible gas alarm
•backlighting of display (turns off automatically
after 4 minutes)
•scrolling through parameters
•selecting menus during operation
•Access to the Maintenance level
•validating (Enter)
2
2. . READING MEASUREMENTS
The gas content measured by each of the sensors "in service" can be seen on the alphanumeric
display unit.
It is divided into four independent zones, each one corresponding to a sensor channel.
A maximum of four readings can be displayed simultaneously.
In each field, the reading is displayed as follows:
•Measurement
•Unit
•Gas symbol
•in case of a 5-gas configuration, channel 5 is displayed alternately in field 3 of the
display unit.

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The time is also shown at the bottom of the display unit.
3
3. . STARTING UP
IMPORTANT: In order to avoid random start up during shipment, the BM25 was sent to you with
the power supply switch turned OFF.
For the first power up, you must open the rear cover of the BM25, and switch the button to ON.
During first start-up, or after a period of inactivity longer than one month, the detector must be
charged, then discharged and recharged completely before operation. Additionally, keep in mind
that any portable gas detector must be tested with gas daily before use.
REMINDER: Before starting up the BM25, check that the necessary sensors are connected.
To start-up the BM25, you need only to push this button on the front plate.
During instrument start up, you have a choice of two procedures:
•standard procedure used in most cases
•procedure allowing you to select a reference explosive gas. This procedure is useful when
checking for a specific gas (town gas, butane, etc.).
INTERRUPTEUR

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3.1. Starting up in standard mode
•Briefly press the "On/Off/Enter" key:
•the instrument carries out a visual and audio test phase for a few seconds and indicates:
-the INDUSTRIAL SCIENTIFIC-logo
-the version of the instrument software, date, code and serial number
-the pre-programmed values of the alarm thresholds for each sensor channel
-the current readings.
Note:when the instrument is operating, it emits a visual confirmation flash in order to indicate that
the BM25 gas detector is operating correctly. Upon request or by using COM 2100 software, this
signal can be cancelled and the interval betweeneach signal can be modified.
3.2. Starting up with choice of reference explosive gas
Hold down the "Lighting" or "Acknowledge" button
•switch on the instrument by pressing the “On/Off/Enter” key
•release both buttons
•the display unit shows the INDUSTRIAL SCIENTIFIC-logo for a few seconds while it
performs self-tests. It then displays the list of pre-programmed gases, with the currently
selected gas in the dark field.
Choosing a new reference gas:
•each time you press the “Acknowledge” button, the list scrolls downwards and each time
you press the “Lighting” button, the list scrolls upwards. thirty-one reference gases are
pre-programmed in the range 0-100% LEL (or 0-5% volume CH4). A thirty-second (32)
“Other” lets you select a gas according to your specific requirements. The data specific to
that gas is entered in the workshop.
•Accept the choice: when the chosen gas is displayed, press the “Enter” key.
After a testing phase, the explosive reference gas is now the gas that was selected.
If you do not select a gas after a certain amount of time, the gas detector switches to normal phase
without changing the reference gas, therefore aborting the procedure.
3.3. Start-up test and calibration due
During start-up, the instrument performs a self-test.
•If tests are incorrect, the instrument switches to “fault” mode (audible signal and
continuous visual indication).
•If tests are correct the instrument is ready to use.
CALIBRATION DUE

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If, after starting up, the date of calibration has expired, the instrument triggers a calibration due
signal on the channel concerned. This calibration due signal can be cancelled and the gas detector is
still in use but must be calibrated.
4
4. . SHUTTING DOWN
To shut down, hold down the "On/Off" button for three seconds.
On the display unit, the countdown "Stop 3,2,1" is displayed until the instrument is switched off.
In more recent gas detector versions (1/2007), it is necessary to release the ON/OFF button, then
press the key again (follow the on-screen instructions).
When the gas detector is switched off, the set values (sensor adjustment data, alarm thresholds,
histogram, etc.) are saved.
5
5. . DISPLAY BACKLIGHTING
Measurements can be read in dark places by pressing the "Lighting" button. This lighting is
automatically deactivated after 4 minutes.
The display unit backlighting is automatically activated in case of an alarm or fault.
6
6. . SCROLLING THROUGH SET PARAMETERS
When the instrument is in normal operating mode, you can consult a series of data on gas
measurements and also the instrument's internal data (remaining battery time, date and time).
While the instrument is in normal operation, press the "Lighting" button repeatedly to scroll through
the parameters for each sensor channel
-display unit backlighting and date
-measurement location and operator’s name (only with “roundsman” option activated:
see Section 6.1.)
-remaining battery time in a bar graph
-indication of minimums detected by each sensor
-indication of maximums detected by each sensor
-STEL of each “toxic” channel
-TWA of each “toxic” channel
-Message stating “Entrez le code de maintenance” (Enter maintenance code): to access
maintenance menus, specify the four-digit code with the “Acknowledge" and “Lighting”
buttons.
-If the code entered is incorrect: return to normal display
-To exit the list before the end: press the “Acknowledge” button.
6.1. “Roundsman” function
If the instrument is equipped with the "Roundsman" function (optional), a list of names can be pre-
programmed using the COM 2100 software. This list can be consulted manually via the keypad.
To change the name or location, as follows:
-current location/name
-enter

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-scroll down or up through pre-programmed list using the “Acknowledgment” and
“Lighting” button
-enter (to select the new name)
-acknowledge (to return to normal mode)
-
6.2. Re-initialization of MIN/MAX
Pushing Acknowledge and Lighting simultaneously restores “min and max” values to the current
measurement value. An audible beep confirms the action.
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7. . ALARMS
The BM25 is equipped with two types of alarm signals:
-Visual alarms: messages in uncoded mode displayed, a 360° red light visible from all
directions
-Audible alarms two powerful horns (103 dB @ 1m.)
7.1. “Gas” alarms
•Two instant thresholds per channel for Explo, Toxic or Oxygen
•High and low thresholds on oxygen channel (2 optional low thresholds)
•1 instant threshold on the catharometric channel.
•Exposure limit (STEL) corresponding to a sliding average of measurements over 15
minutes (depending on the country) for each channel equipped with a toxic gas sensor.
•Mean exposure (TWA) corresponding to a sliding average of measurements over eight
hours for each channel equipped with a toxic gas sensor.
Hence, as soon as the predefined alarm thresholds are exceeded on at least one channel, the gas
detector triggers a pulsed-tone audio and light signal (flashing red light). The alarm message or
messages (FAULT, ALARM, TWA, STEL, min., etc.) and the reading value appear on the display
unit.
In case of a gas alarm, the gas detector displays the maximum value detected until
acknowledgement.
7.2. Fault alarms
Faults can be classified into two categories:
Alarm types:
Gas alarm 1: two-tone
Gas alarm 2: two-tone fast
Alarm transfer: two-tone slow
Fault: single-tone

15
•Faults concerning sensors: out of range, worn sensors, request for calibration in the case
of a major deviation during auto-adjustment. These faults generate messages on the
display unit, a visual alarm (steady red light) and a steady audible alarm.
•Faults concerning the instrument itself (discharged batteries or electronic fault). The
corresponding fault message appears at the bottom of the display unit. It takes priority
over all other sensor-related messages.
Examples of information which may be brought to the user's attention
vBattery pre-alarm warning
•The remaining battery life is at least 20 minutes, during this phase, measurements are still
provided, only audible beep can be acknowledged.
•Battery fault: The BM25 is no longer measuring, fault is not acknowledgeable.
v" > 100% LEL: outside range" in explosive channel
This concerns only the explosive channeland if there is no catharometric sensor ( 0 to 100%
vol).
In this case: -the display of the channel concerned is frozen
-it is impossible to acknowledge the continuous audio signal
-the general alarm indicator lights come on in steady mode
-power to the explosive gas sensor (LEL) is cut off for its protection
Normal operating conditions can be restored by stopping and restarting the BM25 gas
detector (this operation must be performed outside the hazardous area)
v“Outside range” for toxic gas and oxygen
•negative fault (reading below -20% of the scale), acknowledged automatically
•positive fault (scale exceeded by 120%), must be manually acknowledged.
7.3. Acknowledging gas alarms
7.3.1. Manually acknowledging gas alarms
Pressing the “Acknowledge” button stops the audible alarm, but the alarm indicator light flashes
until the measurement is lower than the programmed alarm threshold. As soon as the measurement
returns within the defined limits, the visual signal is automatically stopped.
In standard configurations, the audible alarm will be reactivated after 2 minutes if the gas level is
still above pre-defined limit(s) (this feature can be disengaged by request).
7.3.2. Acknowledging alarms automatically
By request, it is possible to automatically stop gas alarms as soon as the concerned gas levels
exceed the pre-defined threshold without pressing the “Acknowledge” button.

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7.4. Alarm transfer
The BM25 has two “static” relays: one “gas alarm” relay common (in closing) for all channels and
one “failure” relay common (in opening) for all channels. The alarm relay is configured through
COM2100.
The BM25 is also equipped with two logic inputs (TOR):
-1 input dedicated to remote acknowledgment
-1 input dedicated to alarm triggering
These inputs are also configured through COM 2100.
Connections: see Chapter III, 2.5.
Several gas detectors can be connected to each other in order to transfer an alarm from one gas
detector to another or to manually trigger an alarm.
IMPORTANT: Imperative parameters for relay outputs
AC I Max 150 mA -V max 30V
DC I Max 150 mA -V max 30 V
Caution: If the BM25 gas detector is used in a explosive atmosphere, it is imperative to consider
output parameters, since contact must not impair the intrinsic safety of the gas detector. These
parameters are mentioned in the Special Instructions section for use in ATEX areas.
INDUSTRIAL SCIENTIFIC-shall not, in any event, be liable for failure to follow regulations.
8
8. . MEASUREMENTS
2 relay outputs (default and gas) and 2 logic inputs
(remote acknowledged and alarm transfer)

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Caution: measurements can be affected by high or low oxygen concentrations. Any reading
rapidly changing from too high (exceeding the scale) to too low can in fact indicate a
hazardous gas level higher than the measurement scale.
8.1. Display of instantaneous readings
8.1.1. Diffusion mode
All the instantaneous readings regarding gases are displayed in continuous mode.
The display unit is divided into four separate fields (quadrants).
Therefore, the operator can read:
•the measurement
•the measuring unit preceding the gas symbol
8.1.2. With electric pump systems
Caution: you must place a cover on the gas detector as indicated
•Wait a few seconds to read measurements. Any anomaly in the pump system is indicated
by an audible alarm and on the display unit
Caution: do not forget to remove the cover to return to diffusion mode.
8.1.3. With manual pump systems
Place the calibration pipe as shown
Wait for measurements to stabilize before recording them. They could be over-estimated (explosive
gas) or under-estimated (oxygen) during manual pumping due to air movement and system draining.
Caution: do not forget to remove the pipe to get back to diffusion mode.
8.2. Automatic range change « 0-100 % Gas »
With a explosimetric % LEL/ catharometric ( % vol) sensor and with an oxygene sensor
( mandatory in this case), the BM25 switches automatically from the gas explosibles measure range
“0-100% LEL” to the range “0-100% GAS” when the measure is above 100%LEL of the selected
gas reference.
Injection cover to be plug
ged to a
sampling kit (hose + probe).

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NB : For this operation type, the BM25 must be equipped with an oxygen sensor.
The letter K diplay confirms this mode.
8.3. Memorizing histogram measurements
Depending on the version, the BM25 gas detector can memorize measurements so that they can be
restored later on a computer.
The "Histogram’s" function can be used to output values and events memorized by BM25 during its
operating period to a computer (a workstation, for example). Resetting of the data contained in the
histogram memory can only be performed with a computer. Switching off the gas detector has no
effect on memorized data.
8.3.1. Operating principle, memorized items:
The BM25 stores sets of data as soon as it is started, and then in cyclic mode. Each of these sets or
threads (with their pre-programmed specifications) has the same structure.
A thread contains:
•information on measurement channels
•the mean measurements of concentrations on each sensor in operation, over the period of
storage intervals (configurable)
•the events on each channel:
-resetting
-fault
-instantaneous or mean alarms
-types of maintenance requested (programming, calibration, sensor replacement)
-date and time
-battery in discharged state
-auto-adjustment request
-maintenance function request.
8.3.2. Memory capacity
The gas detector can store about 200,000 measurement points.
If the quantity of data to be stored exceeds the gas detector’s storage capacity, the oldest data are
lost.
8.3.3. Data storage time
The data stored by the BM25 are stored even if the instrument is not used for a long time (out of
service).
I
II II I. . S Sp pe ec ci ia al l i in ns st tr ru uc ct ti io on ns s f fo or r u us se e i in n e ex xp pl lo os si iv ve e

19
a
at tm mo os sp ph he er re es s o or r h ha az za ar rd do ou us s l lo oc ca at ti io on ns s
Information in following paragraphs must be taken into account and followed by the person
responsible for the equipment installation site. Refer to the provisions of European ATEX Directive
1999/92/EC, the Canadian Electrical Code, or to the applicable local legislation, relevant to
improving safety protection and health of workers exposed to the risks of explosive atmospheres.
For intrinsically safe installations and especially for connections to the BM25, keep in mind
that the person responsible for the IS installation, called “the system designer,” must establish a
system document demonstrating that the whole BM25 system -Cable -- Body device is Intrinsically
Safe (See standard EN 50039 FOR GROUP II and EN 50394-1 for group I for the preparation of
this document).
ATEX Essential Safety and Health requirements
comply with the following standards:
EN 50014 of June 1997 + Amendments 1 and 2
EN 50018 of November 2000 +amendment 1
EN 50020 of June 2002
EN 50284 of January 1999
EN 50303 of July 2000
1
1. . Hazardous areas and general rules
The BM25 can be used in explosive atmospheres in Group II surface industries and Group I mines
containing firedamp.
The ambient temperature range for its use is from –20° C to + 55° C.
Depending on the type of sensors used on the instrument, categories covered by the gas detector
following the European Directive 94/9/CE are:
a) Device with any type of sensor block except infrared block
-Surface industries: Category 1G, use in zones 0,1 or 2
-Mines containing firedamp : category M1, whatever the gas value
b) Device with any type of sensor block including infrared block
-Surface industries: Category 2G, use in zones 1 or 2
-Mines containing firedamp : category M2, use below a gas limit value
The following operations are prohibitedin explosive atmospheres:
-opening of the instrument: sensor cover or rear cover
-recharging of batteries
-link-up with a computer
All servicing, adjustment and maintenance operations must be performed by duly approved
personnel.
In order to avoid any risk of explosion by electrostatic discharges, the display unit glass and
indicator light must be cleaned only with a damp cloth. The battery pack must be replaced by the
original part specified by the manufacturer – INDUSTRIAL SCIENTIFIC-p/n 6 311 082.
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2. . ATEX areas: input/output parameters

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2.1. Gas detector recharge connector
It is recommended that the charger provided by INDUSTRIAL SCIENTIFIC-be used outside of the
ATEX (hazardous) area. When the recharging is done by a charger other than the one provided by
INDUSTRIAL SCIENTIFIC-OLDHAM, its characteristics must not exceed a voltage of 30VDC
and a current of 30 mA
2.2. Connector for alarm outputs / fault and digital TOR inputs
The characteristics of static relay contacts inputs opto isolated and built into the gas detector are:
U in = 30 V max I in = 150 mA max
The output characteristics of TOR digital inputs built into the gas detector are:
U out = 5 V max I out = 50 mA max L out = 8 mH C out = 7 µF
Only zero voltage circuits can connect to the digital inputs, i.e. Uin = 0V and Iin = 0A.
Caution:The two previous circuits are separate intrinsic circuits. The cables connected to the ends
of these circuits must comply with the requirements for intrinsically safe circuit wiring:
type of cables, insulation voltage, insulation, linear capacity and inductance. Refer to
national and international standards, for example EN 60079-14.
A system log should be established by the person responsible for the installation as explained above.
2.3. External power connector for maintenance of the battery pack
The output characteristics of each external power source connected to the BM25 are:
-Either: Po=0.81W Uo =28V Io=115 mA Lo=2 mH Co=0.08µF
For instance power supply 5302B byPr. Electronics
II (1) G [ EEx ia ] IIC DEMKO 99ATEX126257)
-Or: Po=1.3W Uo =23.5V Io=160 mA Lo=1 mH Co=0.132µF
For instance BXNEO1 by Georgin
I (M1) II (1) G/D [ EEx ia ] I [ EEx ia ] IIC LCIE 02ATEX6104X)
The BM25 gas detector has a Co=0 and a Lo=0 on external power connectors.
It is possible to connect two external power supplies on the connector in accordance with the rules
specified in the previous paragraph.
2.4. Connector accessories / options
Figure 1 shows the different connection options for the BM25.
The connectors are located on the BM25 sides.
Remark : the unused connectors will be equipped with their cap.
2.5. Reference for electrical signals of connectors

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Figure 1 shows the different connections of the BM25. The connectors are located on the sides of
the gas detector.
Note:Unused connectors must be equipped with their protective cap.