Rae MultiRAE PLUS PGM-50 Operation And Maintenance Manual

MultiRAE PLUS

MULTI-GAS MONITOR

PGM-50

OPERATION AND MAINTENANCE

MANUAL

(Document No.: 008-4001)

Rev. G

RAE SYSTEMS INC.

1339 Moffett Park Drive

Sunnyvale, CA 94089

October 2001

RAE Systems Product Line

§ Gas Detection Tubes & Pumps

§ SampleRAE Electronic Sampling Pump

§ MultiRAE PLUS Multi-gas Monitors

§ MultiRAE IR Multi-gas Monitors w/CO2

§ MultiRAE Confined Space Monitor

§ QRAE PLUS Multi-gas Monitors

§ QRAE Confined Space Monitor

§ VRAE Five-Gas Monitors

§ DRAE Two-Gas Monitors

§ MiniRAE 2000 Portable VOC Monitor (PID)

§ ppbRAE Portable ppb-Level VOC Monitor (PID)

§ UltraRAE Specific Compound Monitor

§ CDRAE Corona Discharge VOC Monitor

§ ToxiRAE PLUS PID Monitor

§ ToxiRAE PLUS Single Gas Monitors

§ ToxiRAE PLUS Oxygen Monitor

§ ToxiRAE PLUS Combustible Gas Monitor

§ MiniRAE PLUS Classic PID

§ ModuRAE Fixed System PID

§ AreaRAE Wireless Multi-point, Multi-gas Detection

Systems

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You will be updated on new products, technical advisory notices, new
accessories and much more. Thank you for your purchase!

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Table of Contents

1. GENERAL INFORMATION.......................................1-1

1.1 General Specifications...........................................1-2

2. OPERATION OF MULTIRAE PLUS.........................2-1

2.1 Physical Description..............................................2-2

2.2 Keys and Display....................................................2-4

2.3 Power On/Off.........................................................2-7

2.4 Operations.............................................................2-10

2.5 Alarm Signals........................................................2-17

2.6 Back Light.............................................................2-20

2.7 Preset Alarm Limits and Calibration..................2-21

2.8 Integrated Sampling Pump...................................2-22

2.9 Datalogging...........................................................2-24

3. OPERATION OF ACCESSORIES..............................3-1

3.1 Battery Charging Operation...................................3-2

3.2 Alkaline Battery Adapter........................................3-4

3.3 Water Trap Filter....................................................3-5

3.4 Remote Sampling Probe or Tygon Tubing...........3-6

3.5 Dilution Fitting.......................................................3-7

3.6 Calibration Adapter................................................3-8

4. PROGRAMMING OF MULTIRAE PLUS...............4-1

4.1 Programming Mode ...............................................4-2

4.2 Keys for Programming Mode ...............................4-4

4.3 Entering into Programming Menu........................4-5

4.4 Calibration of MultiRAE PLUS Monitor.............4-7

4.4.1 Fresh Air Calibration.......................................4-10

4.4.2 Multiple Sensor Calibration..............................4-11

4.4.3 Single Sensor Calibration.................................4-14

4.4.4 Modify Span Gas Value...................................4-17

4.4.5 Change LEL/VOC Span Gas...........................4-18

4.5 Change Alarm Limits...........................................4-20

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4.6 View or Change Datalog......................................4-22

4.6.1 Reset Peak and Minimum ................................4-23

4.6.2 Clear All Data 4-24

4.6.3 Change Datalog Period....................................4-25

4.6.4 Select Data Type.............................................4-26

4.6.5 View Datalog..................................................4-27

4.6.6 Enable / Disable Datalog..................................4-28

4.7 Change Monitor Setup.........................................4-29

4.7.1 Change Site ID 4-30

4.7.2 Change Alarm Mode.......................................4-31

4.7.3 Change User Mode.........................................4-32

4.7.4 Change Real Time Clock.................................4-33

4.7.5 Change Back Light Mode................................4-34

4.7.6 Change Password............................................4-35

4.7.7 Change Pump Speed.......................................4-36

4.7.8 Change Averaging Method ..............................4-37

4.8 Change Sensor Configuration..............................4-38

4.8.1 Change LEL/VOC Gas Selection.....................4-40

4.8.2 Enable / Disable Sensor...................................4-44

4.8.3 Change Dilution Ratio ......................................4-45

4.8.4 Change PID Lamp Type..................................4-46

4.9 Exit Programming Mode .....................................4-47

5. COMPUTER INTERFACE

FOR MULTIRAE PLUS...........................................5-1

5.1 Install ProRAE-Suite Software.............................5-2

5.2 Connect MultiRAE PLUS to PC...........................5-4

5.3 Start ProRAE-Suite Software................................5-4

5.4 Setup Communication Port...................................5-7

5.5 Processing the Configuration Data.......................5-8

5.5.1 Editing the Configuration Data............................5-9

5.5.2 Send Configuration to MultiRAE Plus...............5-21

5.5.3 Saving Configuration Data................................5-22

5.5.4 Configuring All Settings....................................5-23

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5.6 Processing the Logged Data................................5-24

5.6.1 Receive Data from MultiRAE PLUS ................5-25

5.6.2 View Logged Data in Text Mode.....................5-26

5.6.3 View STEL/TWA/AVG Value ........................5-28

5.6.4 View Summary Information ..............................5-29

5.6.5 View Logged Data in Graph Mode..................5-30

5.6.6 Export the Displayed Data to a Text File..........5-34

5.6.7 Export Graphic to a File...................................5-35

5.6.8 Print the Logged Data......................................5-36

5.7 Upgrade the Datalog Option................................5-37

5.8 Upgrade the Firmware..........................................5-39

6. THEORY OF OPERATION.........................................6-1

7. MAINTENANCE............................................................7-1

7.1 Battery Replacement..............................................7-2

7.2 Sensor Replacement...............................................7-4

7.3 PID Sensor Cleaning / Replacement.....................7-7

7.4 PID Lamp Care.......................................................7-9

7.5 Sampling Pump Replacement..............................7-11

8. TROUBLESHOOTING.................................................8-1

8.1 Special Diagnostic Mode.......................................8-2

8.2 Troubleshooting Table.........................................8-10

APPENDIX A. QUICK REFERENCE GUIDE.............A-1

APPENDIX B. CORRECTION FACTORS...................B-1

APPENDIX C. MULTIRAE PLUS DATA

CONVERSION TO MICROSOFT EXCEL.............C-1

APPENDIX D. RAE SYSTEMS TECHNICAL

NOTES..............................................................................D-3

APPENDIX E. RAE SYSTEMS APPLICATION

NOTES..............................................................................E-1

APPENDIX F. LITERATURE REQUEST.....................F-1

APPENDIX G. REQUEST FOR RETURN

AUTHORIZATION FORM..........................................G-1

Main Contact Numbers..........................Outer Back Cover

iv

! WARNING !

- DO NOT proceed before reading -

This manual must be carefully read by all
individuals who have or will have the responsibility
for using, maintaining, or servicing this product.

The product will perform as designed only if it is used,
maintained, and serviced in accordance with the
manufacturer's instructions.

CAUTION!!
To reduce the risk of electric shock, turn off power
before removing the monitor cover. Disconnect
the battery before removing sensor module for
service. Never operate the monitor while the cover
is removed. Remove monitor cover and sensor
module only in an area known to be non­hazardous.

The model PGM-50 equipment is classified as to
intrinsic safety for use in class I, division 1, groups
A, B, C, D, or non-hazardous locations only.

v

Special Note

-1-

When the PGM-50 Multi-gas Monitor is taken out from
the transport case and turned on for the first time, there
may be some residual organic or inorganic vapor
trapped inside the detector chamber. The initial PID or
toxic sensor reading may indicate a few ppm. Ensure an
area free of organic or toxic vapor and turn on the
monitor. After running for several minutes, the residual
vapor in the detector chamber will be cleared and the
reading should return to zero.

-2-

The battery of the MultiRAE PLUS monitor will
discharge slowly even if it is turned off. If the monitor
has not been charged for 5-7 days, the battery voltage
will be low. Therefore, it is a good practice to always
charge the monitor before using it. It is also
recommended to fully charge the monitor for AT LEAST
10 HOURS before initial use (see Section 7 for more
information on battery charging and replacement).

vi

WARNINGS:

Use only RAE Systems battery packs, part Nos. 500-

0028, 500-0029, or 500-0039. This instrument has

not been tested in an explosive gas/air atmosphere

having an oxygen concentration greater than 21%.

Substitution of components may impair intrinsic

safety. Recharge batteries only in non-hazardous

locations.

AVERTISSEMENT:

Utiliser seulement l'ensemble de batterie RAE

Systems, la reference 500-0028, 500-0029 au 500-

0039. Cet instrument n’a pas été essayé dans une
atmosphère de gaz/air explosive ayant une

concentration d’oxygène plus élevée que 21%. La
substitution de composants puet compromettre la

sécurité intrinsique. Ne charger les batteries que

dans emplacements désignés non dangereuse.

STATIC HAZARD:

Clean only with a damp cloth.

DANGER RISQUE D'ORIGINE ELECTROSTATIQUE:

Nettoyer uniquement avec un chiffon humide.

vii

CAUTION:

For safety reasons this equipment must be operated

and serviced by qualified personnel only. Read and

understand instruction manual completely before

operating or servicing.

ATTENTION:

Pour des raisons de sécurité, cet équipment doit

être utilisé, entretenu et réparé uniquement par un
personnel qualifié. Étudier le manuel d’instructions
en entier avant d’utiliser, d’entretenir ou de réparer

l’équipement.

viii

CAUTION:

Before each day’s usage, sensitivity must be tested

on a known concentration of methane gas equivalent

to 20-50% of full scale concentration. Accuracy

must be within 0 to +20% of actual. Accuracy may

be corrected by calibration.

ATTENTION:

Avant chaque utilisation journalière verifier la
sensibilité avec une concentration connue de

methane equivalente a 20 - 50% de la pleine échelle.

La précision doit être comprise entre 0 - 20% de la

valeur vraie et peut être corrigée par une procédure

diétalonnage.

CAUTION:

Any rapid up-scale reading followed by a declining or

erratic reading may indicate a gas concentration

beyond upper scale limit which may be hazardous.

ATTENTION:

Toute lecture rapide et positive, suivie d’une baisse

subite au erratique de la valeur, peut indiquer une

concentration de gaz hors gamme de détection qui

peut être dangereux.

WARNING:

ix

The calibration of all newly purchased RAE Systems

instruments should be tested by exposing the

sensor(s) to known concentration calibration gas

before the instrument is used or put into service.

For maximum safety, the accuracy of the MultiRAE

PLUS should be checked by exposing the sensor(s)

to known concentration calibration gas before each

day’s use.

AVERTISSEMENT:

La calibration de toute instruments de RAE Systems

doivent être testé en exposant l’instrument a une

concentration de gaz connue par une procédure

diétalonnage avant de mettre en service l’instrument

pour la première fois.

Pour une securite maximale, la sensibilité du

MultiRAE PLUS doit être verifier en exposant

l’instrument a une concentration de gaz connue par

une procédure diétalonnage avant chaque utilisation

journalière.

GENERAL INFORMATION

1 - 1

1. GENERAL INFORMATION

MultiRAE PLUS is a programmable Multi-gas monitor
designed to provide continuous exposure monitoring of
toxic gases, oxygen and combustible gases for workers in
hazardous environments. It monitors three classes of
hazardous gases:
(1) Organic vapors in the ppm range with the supplied

Photo-Ionization Detector (PID) using a 9.8, 10.6 eV
or 11.7 eV gas discharge lamp,

(2) Combustible gases near their lower explosive limits

(LEL) with a catalytic bead sensor, and

(3) Inorganic compounds, including oxygen deficiency,

with the electrochemical sensors.

Other features include:

• Lightweight and Compact

- 16 oz (454 g), Walkman size.

• Dependable and Accurate

- 10 hours monitoring with micro controller.

• User Friendly

- menu driven, intuitive end-use operation.

• Programmable Alarm Thresholds

- audio buzzer & flashing display alarm.

MultiRAE PLUS (PGM-50) consists of: A Multi-gas
Monitor, a battery charger, rubber boot, alkaline battery
adapter, water and dust filters, plus calibration accessories.

GENERAL INFORMATION

1 - 2

1.1 General Specifications

Table 1.1

Multi -Gas Monitor Specification

Dimensions: 4.65”L x 3.0”W x 1.9”H
(11.8 cm x 7.6 cm x 4.8 cm)

Weight: 16 oz (454 g) with battery.
Detector: Up to five sensors (oxygen, combustible,

two toxic and VOC). Electrochemical
sensors for toxic gases and oxygen, photo­ionization detector for ppm level VOCs,
and catalytic sensor for LEL level
combustible gases.

Battery: Rechargeable, 4.8V/1100 mAh Li ion or

4.8V/1700 mAh Ni-Cd battery pack with
built-in charger (10 hours charge time ) or

a 4 AA alkaline battery adapter.
Operating Time: Up to 10 hours continuous operation.
Display: 2 line, 16 digit LCD with LED back light

automatically in dim light.
Key-pads: 1 operation key and 2 programming keys.
Direct Readout: Instantaneous values (up to 5), sensor

name, high and low values for all detectors,

TWA and STEL value s for toxic and VOCs,

battery voltage and elapsed time.
(Continued)

GENERAL INFORMATION

1 - 3

Multi -Gas Monitor Specification
(Continued)

Alarm Settings: Separate alarm limit settings for TWA,

STEL, Low and High alarm.
Range, Resolution and Response Time (t90 diffusion):
CO 0-500 ppm 1 ppm 20 sec
H2S 0-100 ppm 1 ppm 30 sec
SO

2

0-20 ppm 0.1 ppm 15 sec
NO 0-250 ppm 1 ppm 20 sec
NO

2

0-20 ppm 0.1 ppm 25 sec
Cl2 0-10 ppm 0.1 ppm 60 sec
O2 0-30 % 0.1 % 15 sec
VOC 0-200 ppm 0.1 ppm 10 sec
VOC 200-2000 ppm 1 ppm 10 sec
LEL 0-100 % 1 % 15 sec
HCN 0-100 ppm 1 ppm 60 sec
NH3 0-50 ppm 1 ppm 150 sec
PH3 0-5 ppm 0.1 ppm 60 sec

Alarm: 90 dB buzzer and flashing red LED to

indicate exceeded preset limits, low
battery, or sensor failure.

Calibration: Two point field calibration for fresh air

and standard reference gases.
Attachment: Rubber boot, wrist strap, belt clip.
Sampling Pump: Internal integrated with 300 cc/min flow

rate (high setting).
Protection: Password protected calibration settings,

alarm limits, and data.

GENERAL INFORMATION

1 - 4

Multi -Gas Monitor Specification
(continued)

Intrinsic Safety: UL & cUL Class 1, Division I, Group

A,B,C,D (US & Canada), EEx ia IIC T4

(Europe).
EM Immunity: No effect when exposed to 0.43 mW /cm2

RF interference (5 watt transmitter at 12

inches).
Data Storage: 20,000 readings (64 hours, 5 channels at 1

minute interval) in non-volatile memory.
Datalog Interval: Programmable 1- 3600 sec.
External Alarm: Optional plug in pen size vibration alarm or

earphone.
Communication: Upload data to PC and Download monitor

setup from PC through RS-232 link to

serial port on PC.
Temperature: -20o to 45oC (-4o to 113o F).
Humidity: 0 % to 95% relative humidity.

(non-condensing)
Configuration: 2, 3, 4 and 5 gas with / without pump

and with / without datalogging.

OPERATION OF MULTIRAE PLUS

2 - 1

2. OPERATION OF MULTIRAE PLUS

The MultiRAE PLUS Monitor gives real time measurements
and activates alarm signals whenever the exposure exceeds
preset limits on any of the five possible sensors. Prior to
factory shipment, the MultiRAE PLUS is pre-set with
default alarm limits and the sensors are pre-calibrated with
standard calibration gas. However, the user should calibrate
the instrument before the first use. After the monitor is
fully charged and calibrated, it is ready for immediate
operation.

OPERATION OF MULTIRAE PLUS

2 - 2

2.1 Physical Description

Figure 2-1 shows the main components of the MultiRAE
PLUS Multi-gas Monitor which include:

Figure 2-1 Major parts of the MultiRAE PLUS
Multi-gas Monitor

• 3 keys for the user to interact with the monitor: 1

operation key and 2 programming keys for normal
operation or programming of the monitor.

• LCD display with back light to show real time and

calculated measurements.

Gas Inlet and Filter

Buzzer &
Gas Outlet

Charge Contact

Serial Port for PC
Communication

Wrist Strap

Programming Keys

LCD Display

LED Alarm

OPERATION OF MULTIRAE PLUS

2 - 3

• Buzzer and red LED for alarm signal whenever the

exposures exceed preset limits and for error
conditions.

• Wrist strap.

• Charge contact for plugging directly to the charging

station.

• Gas entry port.

• Serial communication port for PC interface.

OPERATION OF MULTIRAE PLUS

2 - 4

2.2 Keys and Display

Figure 2-2 shows the LCD display and the keypad on the
front panel of the monitor. The functions of the 3 keys
during normal operation are summarized in Table 2.1 on the
next page:

Figure 2-2 Key-pad and Display of the MultiRAE PLUS
Multi-gas Monitor

Light
sensor

0.1

0.0

0.0

0.0

20.9

MODE

ON

Y/+

N/-

OXY

TOX2

VOC

LEL

TOX1

LED alarm/
charge status

[Mode]
key

[Y/+] Key

[N/-] Key

OPERATION OF MULTIRAE PLUS

2 - 5

Table 2.1

Key Function in Normal Operation

[MODE]: Turn on/off the power* and choose

different display mode.

[N/-]: Toggle on/off the back light. Answer as

“No.”

[Y/+]: Alarm test and alarm acknowledgment
(turn off latched alarm, turn on pump or

LEL sensor). Answer as “Yes.”

* Pressing and holding [MODE] key for 5 seconds turns off
the power to the monitor. Monitor will beep once per
second during power-down sequence. Press [MODE] key
momentarily to choose different display modes (see Section

2.4 for details).

OPERATION OF MULTIRAE PLUS

2 - 6

The Multi-gas Monitor includes a 2-line, 16-digit dot matrix
LCD display. The LCD shows the following eight types of
displays during normal operation if the [MODE] key is
pressed:

• Real time instantaneous gas concentration in ppm for

toxic and VOC gases, % by volume for oxygen and %
LEL for combustible gases.

• Sensor names.

• Peak and minimum gas concentration for toxic, VOC,

oxygen and combustible gases.

• 15 minute Short Term Exposure Level (STEL) values

of the toxic and VOC gases in ppm and 8 hours Time
Weighted Average (TWA).

• Battery voltage and shut off voltage in volts.

• Real time clock, run time and temperature.

• Datalogging mode or “Start / Stop Datalog?” menu to

enable/disable datalogging if manual datalogging
mode is selected.

• LEL or VOC gas names (if the LEL and VOC sensor

are installed).

• “Print Reading?” menu to print the reading to the

RAE Printer.

• “Communicate with PC?” menu to send or receive

data between PC and the MultiRAE PLUS monitor.

OPERATION OF MULTIRAE PLUS

2 - 7

2.3 Power On/Off

To turn on the MultiRAE PLUS Multi-gas Monitor, press

[MODE] key. The audio buzzer will beep once and the

display will show “ON!..” and then “MultiGas Monitor Ver
n.nn” to indicate the software version number. The custom
power-on-name which can be changed by the customer using
the ProRAE Suite Software. The model number, serial
number, current date and time, temperature of the monitor
are displayed next. The monitor will then go through each
sensor socket to check if a valid sensor is installed. If a new
sensor is installed, a message to remind the user to calibrate
the sensor will be displayed followed by a message that the
alarm limits have been reset to default values for the new
sensor. If a sensor reaches its expected end of life, a
“Warranty Expired” message will be displayed.

Next, the monitor displays the preset alarm limits for each
sensor, battery voltage, shut off voltage, user mode, alarm
mode, datalog mode, available data storage memory (in
hours), datalog mode and datalog interval (in seconds) and
then after 10 seconds, the display shows the instantaneous
reading of the gas concentration in ppm and is ready to
monitor gases.

To turn off the MultiRAE PLUS Multi-gas Monitor, pr ess
and hold the [MODE] key for 5 seconds. Monitor will beep
once per second during power-down sequence with a count
down timer showing the number of remaining seconds. The
message “Off!..” flashes on the LCD display and the display
will go blank, indicating that the monitor is turned off.

OPERATION OF MULTIRAE PLUS

2 - 8

Turning off the Multi-gas monitor with the AC charger in
place will result in a display of “Charging..” or “Battery
Charged” and indication of battery voltage. This indicates
that the monitor is off, but the smart charger circuit is now
active.

To turn the unit on from the charge or discharge mode, press
the [MODE] key.

Data protection during power off
When the monitor is turned off, all the current real time data

including TWA, STEL, Peak and elapsed time are erased.
However, the datalog data is preserved in non-volatile
memory. Even if the battery is disconnected, the datalog
data will not be lost. During the power off period, the real
time clock will continue to operate until the battery is
completely drained (usually in 5-7 days without any
charging). If the battery is completely drained or is
disconnected from the monitor for more than 30 minutes,
the real time clock will be lost. In this case, users need to
enter the real time clock information again, as described in
Section 4.

OPERATION OF MULTIRAE PLUS

2 - 9

Datalog versus Non Datalog monitor

There are two versions of the PGM-50 Multi-gas Monitors:
Datalog monitors and Non-Datalog monitors. During power
on sequence, a letter “D” following the version number
indicates that the monitor is configured as a Datalog
monitor. Without the letter “D”, it is a Non-Datalog
monitor.

Users can upgrade a Non-Datalog monitor to a Datalog
monitor. Call the factory for information on how to order
the upgrade kit and follow the instructions described in
Section 5.7 to enable or disable the datalog feature for the
monitor.

OPERATION OF MULTIRAE PLUS

2 - 10

2.4 Operation

The MultiRAE PLUS Multi-gas Monitor offers three
different user modes of operation:

Text mode,
Display mode, and
Programming mode (default mode setting).

The text mode is the simplest mode of operation. The
monitor will display the sensor name after the monitor is
turned on. The user can press the [MODE] key to see the
instantaneous gas concentration reading, battery voltage or
enter the PC communication menu. The user can get into
the calibration mode from text mode to do calibrations, but
cannot change most of the parameters.

In the display mode, the MultiRAE PLUS Multi-gas
Monitor is able to display all the information in the text
mode. In addition, the following information is also
available by pressing the [MODE] key: peak, minimum,
STEL, TWA, run time in hours and minutes, temperature in
degree C, datalog mode (or enable / disable datalogging
operation in manual datalog mode), LEL/VOC gas names,
printing and communication with a PC options. The user
cannot get into the calibration mode from display mode , so
the user cannot do calibration and cannot change any of the
parameters.

In the programming mode , which is the default setting, the
user can perform all of the functions of the display mode. In
addition, the user can get into calibration mode, perform

OPERATION OF MULTIRAE PLUS

2 - 11

calibrations and change any of the parameter in the
calibration mode.

The following is the detail explanation of the displays when
the [MODE] key is pressed

1) The instantaneous reading is the actual gas

concentration in parts per million (ppm) for toxic or
VOC gases, % of volume for oxygen and % of LEL for
combustible gases. The reading is updated once per
second and is shown in the LCD display.

TOX1 VOC TOX2

0 0.0 0
0 20.9

LEL OXY

2) The sensor names are displayed as:
LEL: for combustible gas sensor
VOC: for PID sensor
OXY: for oxygen sensor
CO, H2S, etc.: for up to 2 toxic sensors

TOX1 VOC TOX2

CO VOC H2S
LEL OXY

LEL OXY

OPERATION OF MULTIRAE PLUS

2 - 12

3) The Peak reading is the highest reading of each gas

concentration since the monitor was turned on. The
reading is updated at one-second intervals and is
shown in the LCD display with “Peak” message.

TOX1 VOC TOX2

5 2.0 3
10 Peak 20.9

LEL OXY

4) The Minimum reading is the lowest reading of each gas

concentration since the monitor was turned on. The
reading is updated at one-second interval s and is shown
in the LCD display with “Min” message.

TOX1 VOC TOX2

0 0.0 0
0 Min 19.9

LEL OXY

5) The STEL reading is the last 15 minute average reading

of the gas concentration. The reading is updated once
per minute and is shown in the LCD display with “STEL”
message. For the first 15 minutes, “****” will be
displayed. This reading applies to VOC and toxic gases
only.

TOX1 VOC TOX2

0 0.0 0
STEL

LEL OXY

OPERATION OF MULTIRAE PLUS

2 - 13

6) The TWA reading is the accumulated reading of the gas

concentration divided by 8 hours since the monitor was
turned on. The reading is updated once a minute and is
shown in the LCD display with “TWA” message. This
reading applies to VOC and toxic gases only.

TOX1 VOC TOX2

0 0.0 0
TWA

LEL OXY

7) The battery voltage reading is the current battery

voltage in volts. The reading is updated once per second
and is shown in the LCD display. The shut down voltage
is also shown. Note: A fully charged battery pack
should show 4.8 volts or higher. When the battery
voltage falls below 4.4 volts, a flashing “Bat” will appear
as a warning message. This means there is 20-30
minutes run time left before the monitor will be turned
off automatically, when the battery voltage falls below

4.2 volts.

TOX1 VOC TOX2

Battery = 4.8 V
Shut down at 4.2 V

LEL OXY

OPERATION OF MULTIRAE PLUS

2 - 14

8) The run time reading is the accumulated “On” time in

hours and minutes since the monitor was turned on. The
reading is updated at one minute intervals and is shown
in the LCD display together with the current date, time
and temperature.

TOX1 VOC TOX2

8/3/96 8:30
On = 3:50 20°C

LEL OXY

9) The datalog menu shows the cur rent datalog mode. If

manual datalog mode is selected, the menu will prompt
the user to turn on or off datalogging. Pressing the [Y/+]
key while “Start Datalog?” message is displayed turns on
the datalogging. Likewise, pressing the [Y/+] key while
“Stop Datalog?” message is displayed turns off the
datalogging.

10) The monitor will display the selected LEL and VOC gas

name if the combustible sensor and PID sensor are
installed. When an LEL or VOC gas is selected, the
“calculated” gas concentration based on the built-in
correction factor for that specific gas will be displayed.

11) Print Reading? asks for printing out of the gas

concentration reading. If a serial printer is connected
and ready, pressing the [Y/+] key will print out the
reading.

OPERATION OF MULTIRAE PLUS

2 - 15

12) T he Communicate with PC? menu allows the user to

upload data from the MultiRAE PLUS to a Personal
Computer (PC) or download configuration information
from a PC to the MultiRAE PLUS. Press the [Y/+] key
and the LCD displays the message “Monitor will pause,
OK?” to remind the users that during PC communication,
there will be no real time monitoring of the gas
concentration. Press [Y/+] to proceed and the monitor
enters the communication standby mode . The LCD then
displays “Ready...” Connect the monitor to the serial
port of a PC. The monitor is then ready to receive any
command from a PC (see Section 5 for details on
communications between the MultiRAE PLUS and a
PC).

Note: When the monitor is in communication
standby mode, it stops monitoring the gas
concentration and stops the datalogging.
Datalogging must be manually restarted when
exiting the communication standby mode, unless it
is in automatic datalogging mode.

Displays in text mode:

The four displays are arranged in a “round robin” order:

Sensor name

PC comm?

Instantaneous
reading

Battery voltage

OPERATION OF MULTIRAE PLUS

2 - 16

Displays in display or program mode:

The twelve displays are arranged in a “round robin” order:

To choose a specific display, press the [MODE] key one or
more times until the desired display appears.

Display time out

In all displays, the LCD will automatically return to the
instantaneous reading (in display or program mode) or
sensor name (in text mode) after a one-minute time out
interval if no key is pressed.

Run time/clock

Instantaneous

Reading

Min. value

PC comm?

Peak value

LEL/VOC gas

STEL value

Sensor name

Start/stop datalog?

Battery voltage

TWA value

Print Reading?

OPERATION OF MULTIRAE PLUS

2 - 17

2.5 Alarm Signals

The built-in microcomputer updates the gas concentrations
every second and compares them with the programmed
alarm limits (TWA, STEL, and two instantaneous gas
concentration alarm limit settings: Low & High).
Whenever the concentration exceeds the sensors’ preset
limits, the loud buzzer and red flashing LED are activated
immediately to warn the user of the alarm condition.

In addition, the MultiRAE PLUS will alarm if one of the
following conditions occurs: battery voltage falls below a
pre-set level (4.4 V), failure of the UV lamp, LEL sensor
off, pump stall or when the datalog memory is full. When
the low battery alarm occurs, there will be approximately
20-30 minutes of operating time remaining. When the
battery voltage falls below 4.2 V, the monitor will be turned
off automatically.

Alarm Signal Disabled: It is extremely important to
note that during the following conditions, the alarm
signals are disabled:

1) In PC communication standby mode.

2) In calibration mode (including reviewing datalog
data).

During these modes of operation, real time monitoring of
the gas concentration stops. None of the gas concentrations
will be calculated, including Peak, STEL and TWA.

OPERATION OF MULTIRAE PLUS

2 - 18

Alarm Signal Latching:

It is possible to setup the MultiRAE PLUS from a PC or in
programming mode so that when an alarm condition occurs,
the alarm signals stay on even after the alarm condition is no
longer present. This is called the “latching alarm” mode.
The alternative mode is to automatically reset the alarm
signal when the alarm condition is cleared. The default
alarm mode is automatic reset (see Chapter 4 or 5 for
details on how to set alarm mode).

Alarm Signal Summary:

The various alarm signals are summarized here:

Condition Alarm Signal

Gas exceeds “High
Alarm” limit

3 beeps/flashes per second

plus sensor name on LCD
Gas exceeds “Low
Alarm” limit

2 beeps/flashes per second

plus sensor name on LCD
Gas exceeds STEL 1 beep/flash per second plus

sensor name on LCD
Gas exceeds TWA 1 beep/flash per second plus

sensor name on LCD
Negative Drift or
Over Range

3 beeps/flashes per second

plus NEG or OVR name on

LCD
Pump failure 3 beeps/flash per second plus

“Pump” message on LCD
LEL sensor off 3 beeps/flash per second plus

LEL sensor name and “Off”

message on LCD

OPERATION OF MULTIRAE PLUS

2 - 19

PID lamp failure 3 beeps/flash per second plus

“Lamp” message on LCD
Low battery 1 flash per second, 1 beep per

minute plus “Bat” message on

LCD
Memory full 1 flash per second plus “Mem”

message on LCD

Alarm Signal Testing:

Under normal non-alarm conditions, it is possible to test the
MultiRAE PLUS LED, buzzer and back light by pressing the
[Y/+] key momentarily. The buzzer will beep once and the
LED and back light will flash once to indicate that these

alarm signals are functioning correctly.

WARNING:

The alarm signals are disabled during PC
communication, calibration or datalog review
operation. To reduce the risk of exposure to
hazardous atmospheres, perform PC
communication, calibration or datalog review only in
area known to be non hazardous.

OPERATION OF MULTIRAE PLUS

2 - 20

2.6 Back Light

The LCD display is equipped with an LED back light to assist
in reading the display under poor lighting conditions. This
back light can be turned on manually by pressing and
holding the [N/-] key for one second in normal operation.
The back light can be turned off by pressing [N/-] a second
time. If the [N/-] key is not pressed, the back light will be
turned off automatically after a pre-programmed time-out
period to save power.

In automatic mode, the ambient light is sensed and the back
light will be turned on automatically if the ambient light is
below a threshold level. The back light will be turned off
automatically when the ambient light exceeds the threshold
level.

(See Chapter 4 or 5 for details on how to set back light
mode and time out period from the monitor or from PC.
See Chapter 8 for details on how to set the ambient light
threshold level.)

Note: The LED back light consumes a higher amount of
energy from the battery and shortens the operating time of
the monitor by 20 - 30%.

OPERATION OF MULTIRAE PLUS

2 - 21

2.7 Preset Alarm Limits and Calibration

The MultiRAE PLUS Multi-gas Monitor is factory
calibrated with standard calibration gas, and is programmed
with default alarm limits as listed below. (refer to Chapter 4
or Chapter 5 for programming procedures if new calibration
or alarm limits is required).

Table 2.2

Factory Calibration and Preset Alarm Limits

Gas
ppm

Cal Gas /
Balance

Unit

TWA

STEL Low High

CO 50 / Air ppm 35 100 35 200
H2S 25 / N2 ppm 10 15 10 20
SO2 5 / N2 ppm 2 5 2 10
NO 25 / N2 ppm 25 25 25 50
NO2 5 / Air ppm 1 1 1 10
Cl2 10 / N2 ppm 0.5 1 0.5 5
O2 20.9 / N2 %Vol - - 19.5 23.5
CH4 50 / Air %LEL - - 10 20
HCN 10 / N2 ppm 5 5 5 50
NH3 50 / N2 ppm 25 35 25 50
PH3 5 / N2 ppm 0.3 1 1 2
VOC* 100 / Air ppm 10.0 25.0 50.0 100

*Note: 100 ppm isobutylene gas is used for VOC gas
calibration

OPERATION OF MULTIRAE PLUS

2 - 22

2.8 Integrated Sampling Pump

The MultiRAE PLUS Multi-gas Monitor includes an
integrated sampling pump. This is a diaphragm pump
providing about 300 cc per minute flow rate at the high
setting with the standard filters in place.

A low pump speed of about 200 cc per minute is the factory
default setting, which will increase the battery life by about
5% and result in an increased LEL sensor lifetime (see
Chapter 4 or 5 for details of how to select the pump speed).

The high pump speed setting is required for vapors that are
especially reactive or adsorb easily to instrument surfaces.
Such vapors include Cl2, PH3, NH3, HCN, and semi-volatile
organic compounds like diesel fuel and jet fuels. For such
compounds it is helpful to remove the water trap filter for
normal calibration and operation, which will increase the
pump speed to about 350 cc/min. It is also desirable to use
inert connecting and sampling tubing, such as Teflon instead
of Tygon, and to make connections as short as possible.

The pump is turned on automatically when the monitor is
turned on and remains on during normal operation.

If liquid or other objects are sucked into the water trap in the
inlet port and cause the pump to stall, the electronics of the
monitor will detect the obstruction and shut down the pump
immediately. The alarm will be activated and a flashing error
message “Pump” will be also displayed in the LCD display.

OPERATION OF MULTIRAE PLUS

2 - 23

The user needs to acknowledge the pump shut off condition
by pressing the [Y/+] key to re-start the pump. Different
pump shut-off thresholds are desired for the two pump
settings; this value can be adjusted in the Special Diagnostic
Mode as described in Section 8.1.

OPERATION OF MULTIRAE PLUS

2 - 24

2.9 Datalogging

The MultiRAE PLUS Multi-gas Monitor calculates and
stores the gas readings based on a user-specified datalogging
period and the type of measurement. Two types of gas
measurements, average or peak concentration can be stored
for each sensor during each datalogging interval. The
datalogging interval can be programmed from one second to
60 minutes in one-second increments. In addition, time
stamp, user ID, site ID, serial number, last calibration date,
and alarm limits are also stored. All data is retained in a
non-volatile memory so that it can be down loaded at a later
time to a PC.

Datalog Options

There are four ways to initiate the datalog operation:

- Automatic: Start and stop datalogging automatically when

the monitor is turned on and off.

- Manual: Start and stop datalogging by pressing a key

manually. There is a timer available to setup the maximum
datalogging time.

- Periodic: Start and stop datalogging daily based on a

preset time (hour and minute).

- Scheduled: Start and stop datalogging based on a preset

date and time (month, date, hour and minute).

Choose a datalog option
Most of the datalogging options can be programmed from
the monitor. Additional options can be programmed using a
PC and downloaded to the monitor (see Chapter 5 for details
on how to program various datalogging options).

OPERATION OF MULTIRAE PLUS

2 - 25

Start/stop datalogging manually
If manual datalogging mode has been selected from the
normal operation menu, toggle through the menu using the

[MODE] key until the Start Datalog? prompt is displayed.

Pressing the [Y/+] key turns on datalogging. Likewise,
pressing the [Y/+] key while Stop Datalog? is displayed,
turns off datalogging.

The other three datalogging options will start and stop
automatically without any user intervention:

Datalogging event

Each time a datalogging operation is initiated, a datalog
event is created. Information, such as start time, datalogging
period, alarm limits, etc. will be recorded in the event
header, followed by the measurement data. If more than 900
measurement intervals are recorded in one event, a new
event will be created automatically.

Datalogging pause

Under the following conditions, the datalogging will be
paused automatically:

1) When entering programming mode, datalogging will stop.
Upon exiting the programming mode, the datalogging will
resume.

2) When entering PC Communication standby mode,
datalogging will stop. Upon exiting the PC communication
standby mode, datalogging will resume only if datalogging
mode was set to automatic mode.

In either case, a new datalog event will be created when the
datalogging is resumed.

OPERATION OF MULTIRAE PLUS

3-1

3. OPERATION OF ACCESSORIES

The accessories for MultiRAE PLUS include:

• Battery charger

• Alkaline battery adapter

• Water trap filter and remote sampling probe

• Dilution fitting

• Calibration adapter

WARNING:

To reduce the risk of ignition of hazardous
atmospheres, recharge battery only in area known
to be non hazardous. Remove and replace battery
only in area known to be non hazardous.

Ne charger les batteries que dans emplacements
désignés non dangereuse.

OPERATION OF ACCESSORIES

3 - 2

3.1 Battery Charging Operation

The charging circuit of the MultiRAE PLUS is built into the
monitor. It only needs a regular AC to 12V DC adapter (wall
mount transformer) to charge the monitor.

1. Connect the AC adapter (or the optional automotive

charging adapter) to the DC jack on the MultiRAE PLUS
monitor.

2. The display will ask whether a discharge cycle (see NOTE

on next page) is required, press [N/-] key, and the
charging function will begin. The display will show
“Charging” “Battery = x.x V.” If a key is not pressed
within ten seconds, the charging will begin automatically.

TOX1 VOC TOX2

Charging
Battery = 5.6V

LEL OXY

3. The LED should be red in color when charging. If the

battery is fully charged, the LED will change from red to
green. The red color indicates that the battery is being
charged. The green color indicates that the battery is
fully charged. The display will also indicate “Fully
charged." A completely discharged MultiRAE PLUS
monitor will be charged to full capacity within 10 hours.

OPERATION OF ACCESSORIES

3 - 3

NOTE 1: The latest version of the MultiRAE PLUS monitor
has a smart charging circuitry and algorithm to prevent
overcharging; removing the charger is not necessary.

NOTE 2: After one charging cycle the monitor recognizes
whether Li ion or NiCd batteries are installed. When NiCd
batteries are present, the firmware displays: Deep
Discharge? when the AC adapter is connected. Perform
occasional deep discharge to the NiCd battery to maintain
full capacity by pressing the [Y/+] key when this message
appears. The battery will begin deep discharge followed by a
charge cycle. The deep discharge is useful to remove
memory effects of the NiCd battery, so that the charge
capacity is maintained.

The battery of the MultiRAE PLUS monitor will be dr ained
slowly even if the monitor is turned off. If the monitor has
not been charged for 5-7 days, the battery voltage will be
low.

The factory supplied battery is designed to last for 10 hours
of normal operation ( no alarm, no back light condition) for a
new battery under the best condition. As the battery
becomes older or is subject to adverse conditions (such as
cold ambient temperature), the battery capacity may be
reduced significantly. Li ion batteries do not have a memory
effect and tend provide longer run time even at the same
mAh rating.

OPERATION OF ACCESSORIES

3 - 4

3.2 Alkaline Battery Adapter

An alkaline battery adapter is supplied with each MultiRAE
PLUS kit. It accepts four AA size alkaline batteries and can
be used in place of the Li ion or NiCd battery pack to
provide approximately 12-14 hours of operation. The
adapter is intended to be used in emergency situations when
there is no time to charge the rechargeable batteries.

Figure 3-1 Alkaline Battery Adapter

To install the adapter, remove the cover of the monitor.
Unplug the Li ion or NiCd battery pack from the battery
connector and plug the alkaline battery adapter into the
battery connector.

The internal charging circuit will automatically detect the
alkaline battery adapter and prevent charging of the battery.

Note: The AA Alkaline battery adapter supplied by
RAE Systems Inc. is intrinsically safe!

OPERATION OF ACCESSORIES

3 - 5

3.3 Water Trap Filter

The water trap filter is made of PTFE (Teflon) membrane
with a 0.2 micron pore size to prevent liquid water from
being sucked into the sensor manifold, which would cause
extensive damage to the monitor. It will also prevent any
dust from entering the monitor and will prolong the
operating life of the sensors.

To install the water trap filter, simply slide the Tygon tubing
onto the ribbed inlet port on the monitor. A male Luer
connector fits to the female Luer of the filter. To remove
the filter, disconnect the Luer connector.

The water filter should not be used for normal calibration
and operation with vapors that are especially reactive or
adsorb easily to surfaces. Such vapors include Cl2, PH3,
NH3, HCN, and semi-volatile organic compounds like diesel
fuel and jet fuels. For these compounds the high pump
speed setting should be used (see Section 2.8). It is also
desirable to use inert connecting and sampling tubing, such
as Teflon instead of Tygon, and to make connections as short
as possible.

OPERATION OF ACCESSORIES

3 - 6

3.4 Remote Sampling Probe or Tygon Tubing

An optional 6-foot Teflon remote sampling probe with a
telescoping handle or a 15-foot Tygon tubing are handy
accessories for users to probe areas which are difficult to
reach, such as ceilings, storage tanks, underground man­holes, etc. Connect the male Luer connector at the end of
the remote sampling probe or the Tygon tubing to the female
Luer connector on the water trap filter. The remote
sampling probe or the Tygon tubing is ready for operation.

Teflon remote sampling tubing should be used for reactive
gases such as Cl2, PH3, NH3, HCN, and for semi-volatile
organic compounds like gasoline and jet fuels. A few feet of
Tygon tubing can completely absorb a kerosene-type fuel.
T ygon can be used for the common confined space entry
gases including CO, H2S, and CH4.

OPERATION OF ACCESSORIES

3 - 7

3.5 Dilution Fitting

An optional dilution fitting can be installed together with the
remote sampling probe or Tygon tubing on the gas inlet port
to dilute the gas samples. This fitting is needed if the gas
sample does not contain more than 10% oxygen. This is due
to the fact that the combustible sensor will not function
correctly when the oxygen concentration falls below 10%.
The dilution fitting will increase the oxygen concentration
so that the combustible sensor can still be used under
oxygen deficient conditions. The other use of the dilution
fitting is to measure the combustible, VOC or toxic gas
when the concentration exceeds the upper limit of the
sensor range.

See the dilution fitting instructions for proper installation.
Make sure to set the dilution ratio in the programming mode
(see Section 4.8) so that the correct gas reading will be
displayed when the dilution fitting is used.

WARNING: For this application, the user must have
the monitor or dilution air inlet located in a clean
atmosphere outside the confined space and use a
remote access probe or Tygon tubing to sample the
gas under test.

OPERATION OF ACCESSORIES

3 - 8

3.6 Calibration Adapter

There are two types of calibration adapt er for the MultiRAE
PLUS monitor. The PGM50-4P or PGM50-5P model has a
built-in sampling pump. Therefore, the calibration adapter
for these two models is a simple 6 inch Tygon tubing with a
male Luer connector on one end. During calibration, simply
connect the tubing to the water trap filter on MultiRAE
PLUS and the calibration gas on the other side.
Alternatively, the calibration gas can be sampled 1) from a
Tedlar gas bag, 2) from an open cup or tube using flowing
calibration gas exceeding the pump demand, or 3) using a
demand flow regulator directly from the gas cylinder.

The PGM50-4 model does not have a built-in sampling
pump. A special diffusion calibration adapter is provided.
During calibration, place this adapter over the front cover of
the monitor and connect the Tygon tubing to the regulator on
the gas bottle.

PROGRAMMING OF MULTIRAE

4 - 1

4. PROGRAMMING OF MULTIRAE PLUS

The MultiRAE PLUS Monitor is built with a microcomputer
to provide programming flexibility for the user. Authorized
users can re-calibrate the monitor, change the alarm limits,
change site ID, user ID, datalogging period, real time clock,
etc.

Programming is menu-driven to provide intuitive end-user
operation. The display shows the menu options, and the key
pad is used for menu selection and data entry.

Note: The real time monitoring of the gas
concentration continues while in the programming
mode. However, during the calibration or review
datalog procedures, the real time monitoring will
pause until the procedures are completed. In
addition, entering programming mode will pause the
datalogging operation automatically. After exiting
programming mode, datalogging operation will
resume.

PROGRAMMING OF MULTIRAE

4 - 2

4.1 Programming Mode

The MultiRAE PLUS has three user modes: text, display
and programming mode. The user can access the
programming function only if they are in the programming
mode (or from text mode with password). If the monitor is
set to display mode, the user cannot enter the programming
menu. In this case, the user mode can be changed only
through a PC (see Section 5.0 for details on setting up the
user mode).

The programming mode allows users to change the setup
in the monitor, calibrate the monitor, modify the sensor
configuration and enter user information, etc. The
programming functions are organized in a three tier menu
structure. Table 4.1 shows the first tier of the programming
menu. Each menu item includes several sub-menus to
perform additional programming functions. Appendix A
shows a more detailed menu tree structure.

Table 4.1

Programming Menu

Calibrate Monitor?
Change Alarm Limits?
View or Change Datalog?
Change Monitor Setup?
Change Sensor Configuration?

PROGRAMMING OF MULTIRAE

4 - 3

Security Level

There are three levels of security in the MultiRAE PLUS
programming mode to provide further protection against
unauthorized changes to the monitor alarm settings and other
settings. The level 2 security allows a user to enter
programming mode without any restriction. This is the
default security setting. The level 1 security requires a 4
digits password to enter programming mode. Level 0
security allows a user to enter the programming mode
without any password checking, as in the level 2. However,
it does not allow a user to save any changes to the alarm
limits, real time clock, correction factor, user and site
information, etc. A user can still perform calibration with
level 0 security. The security level must be set using a PC
(see Chapter 5 for details on setting up the security level).

Once inside the programming mode, LCD will display the
first menu. Each subsequent menu item can be viewed by
pressing the [N/-] repeatedly until the desired menu is
displayed. To enter the sub-menu of a particular menu, press
the [Y/+] key and the sub-menu will be displayed.

To exit the programming mode and return to the normal
operation, press the [MODE] key at any of the first tier menu
displays.

PROGRAMMING OF MULTIRAE

4 - 4

4.2 Keys for Programming Mode

The three keys perform a different set of functions during
the programming mode as summarized below.

Table 4.2

Key Function in Programming Menu

[MODE]: Exit menu when press momentarily or

exit data entry mode when pressed and
held for 1 second

[Y/+]: Increase numerical value for data entry or

confirm (yes) for a question

[N/-]: Decrease numerical value for data entry

or deny (no) for a question

PROGRAMMING OF MULTIRAE

4 - 5

4.3 Entering into Programming Menu

1. Turn on the MultiRAE PLUS monitor (refer to Section

2.3 for the power on sequence).

2. Press and hold down both [MODE] and [N/-] keys for

three seconds to enter programming mode. Note: This
is to prevent a user from entering the programming mode
by accident.

3. If the security level is 0 or 2, after holding down two

keys for 3 seconds, the monitor should enter the
programming mode and the first menu item “Calibrate
Monitor?” will be displayed.

4. If the security level is 1, or user mode is text mode, after

holding down the two keys for three seconds, the display
will show “Enter Password = 0000” with the left-most
digit flashing. The user should enter a password starting
from this flashing digit.

Note 1: Prior to factory shipment, the MultiRAE PLUS

monitor was installed with “0000” as the default
password.

Note 2: For added security, “0000” is always displayed

instead of the actual password at this step.

PROGRAMMING OF MULTIRAE

4 - 6

5. If the correct digit value is not “0”, use the [Y/+] key or

[N/-] key to increase or decrease the digit value. Then

press [MODE] key momentarily to confirm the digit
value. Display shows the actual digit entered and moves
the flashing cursor to the next digit (to the right).

6. Repeat Step 5 until all four digits are entered. Press and

hold [MODE] for one second.

7. If the entered password is correct, the monitor enters the

programming menu. The first menu item “Calibrate
Monitor?” will be displayed.

8. If the password is incorrect, the display shows “Wrong

Password???” and returns to the regular display of
instantaneous gas readings.

9. If the User mode is set to display mode, a message

“Display Only! Cannot enter....” will be shown.

PROGRAMMING OF MULTIRAE

4 - 7

4.4 Calibration of MultiRAE PLUS Monitor

CALIBRATION WARNINGS:

The calibration of all newly purchased RAE Systems

instruments should be tested by exposing the

sensor(s) to known concentration calibration gas

before the instrument is used or put into service.

For maximum safety, the accuracy of the MultiRAE

PLUS should be checked by exposing the sensor(s)

to known concentration calibration gas before each

day’s use.

In programming mode, the user may re-calibrate the sensors
in the MultiRAE PLUS monitor. This is a two-point
calibration process using “fresh air“ and the standard
reference gas. First, a “fresh air” which contains 20.9%
oxygen and no detectable VOC, toxic or combustible gases
is used to set the zero point for each sensor. Then a standard
reference gas, which contains a known concentration of a
given gas, is used to set the second point of reference (also
known as span gas). The two-point calibration procedure is
detailed below. Table 4.3 shows the sub-menus for
calibration operations.

Table 4.3

PROGRAMMING OF MULTIRAE

4 - 8

Calibration Sub-Menu

Fresh Air Calibration?
Multiple Sensor Calibration?
Single Sensor Calibration?
Modify Span Gas Value?
Change LEL/VOC Span Gas?

The preferred calibration method for monitors with pumps is
to place the calibration gas in a gas sample bag (Tedlar
bag). Connect the bag to the MultiRAE PLUS gas inlet port
when you are ready to perform the calibration. Users may
find it more convenient to connect the MultiRAE PLUS
directly to the gas bottle using a flow-on-demand type
regulator. Calibration through such a regulator will produce
similar results to the sample bag method with most gases,
but flow-on-demand regulators are not recommended with
H2S. In an emergency, the MultiRAE PLUS can also be
calibrated directly from a fixed flow regulator with a flow
rate between 0.5 and 1.0 liters per minute.

MultiRAE PLUS diffusion monitors must be calibrated
using a fixed flow regulator with a flow rate between 0.5 and

1.0 liters per minute. Diffusion monitors are supplied with a
special calibration adapter that covers the gas diffusion port.

The calibration adapter links up the inlet port of the
MultiRAE PLUS Monitor to the gas sample bag (see Figure
4-1).

PROGRAMMING OF MULTIRAE

4 - 9

Figure 4-1 Connection of Calibration Gas

MultiRAE PLUS diffusion monitors must be calibrated
using a fixed flow regulator with a flow rate between 0.5 and

1.0 liters per minute. Diffusion monitors are supplied with a
special calibration adapter that covers the gas diffusion port.

PROGRAMMING OF MULTIRAE

4 - 10

4.4.1 Fresh Air Calibration

This procedure determines the zero point of the sensor
calibration curve. To perform fresh air calibration, the
calibration adapter and a bottle of “fresh” air (optional) are
required. The “fresh” air is clean dry air with 20.9 % oxygen
concentration and without any organic, toxic or c ombustible
gases or impurities. If such an air bottle is not available, any
clean ambient air without detectable contaminant can also be
used. A charcoal filter should be used if one is not sure of
the ambient air’s purity.

1. “Calibrate Monitor?” is the first menu item in Table 4.1.

Press [Y/+] to perform calibration. The first sub-menu
shows: “Fresh Air Calibration?”

2. If the “fresh” air bottle is available, twist on the

calibration adapter over the inlet port of the MultiRAE

PLUS Monitor and connect the othe r end of the tube to

the fresh gas bottle. If the “fresh” air bottle is not
available, simply leave the monitor in an area free of any
detectable vapor.

3. Press the [Y/+] key to start “fresh air calibration” of the

monitor. The display shows “zero ...in progress”
followed by the name of each sensor and the message
“zeroed”. The display should show a reading of “20.9”
for the oxygen sensor and “0.0”, or a very small number,
for all other sensors.

4. After about a 5 second pause, the display will show the

message “Zero Cal Done!” and move to the next sub­menu “Multiple Sensor Calibration?”

PROGRAMMING OF MULTIRAE

4 - 11

4.4.2 Multiple Sensor Calibration

T his function simultaneously determines the second point of
calibration curves for multiple sensors in the monitor.
Mixed standard reference gases is needed to perform this
procedure. The user can choose several gas mixtures to be
used in multiple-sensor calibration. Connect the tube to the
sampling bag filled with mixed gas as shown in Figure 4-1.

1. Continuing from Step 4 of the previous Section, the

display should show “ Multiple Sensor Calibration?”
Press the [Y/+] key. The display shows all the pre­selected gases for the sampling bag filled with mixed gas
and “OK?” question. Press [Y/+] key to accept the
multiple sensor selection and start the calibration, or
press the [N/-] key to modify the sensor selection and go
to Step 7.

TOX1 VOC TOX2

CO - - - - H2S
LEL OK? OXY

LEL OXY

2. Turn on the valve of the sampling bag to start the flow of

the span gas. Display shows “Apply Mixed Gas” and will
wait for the calibration gas to reach the sensor. When
the calibration gas has reached the sensor the display will
show “calibration in progress… 60” with the countdown
timer shows the number of remaining seconds while the
monitor performs calibration. When the countdown
timer reaches 0, the display shows the name of each
sensor, the message “cal’ed!” and the calibrated values
for each gas. If no gas has reached the sensor after 60
seconds, the display will show “No gas flow…” and abort
the calibration.

PROGRAMMING OF MULTIRAE

4 - 12

Note: the readings should be very close to the span gas
values. After about 5 seconds pause, the display will
show the message “Span Cal Done! Turn Off Gas”

3. This completes the multiple sensor calibration procedure

and moves to the next sub-menu item.

4. Turn off the flow of gas. Disconnect the calibration

adapter from the MultiRAE PLUS Monitor.

5. If the sensor failed the calibration, the sensor name and

an error message “failed, continue?” will appear. Press
the [N/-] or [MODE] key to abort the calibration and
move directly to the next sub-menu item. Press the
[Y/+] key to continue the next sensor calibration. In
either case, the calibration data for the current sensor is
not changed.

6. From Step 1, if the [N/-] key is pressed, the display

shows all the sensor names which are selected for
multiple sensor calibration with the cursor blinking at the
first sensor location.

TOX1 VOC TOX2

CO* - - - - H2S*
LEL* OK? O2

LEL OXY

Press the [Y/+] key to select the sensor and the [N/-] key
to de-select the sensor. A previously selected sensor
will show an “*” next to the sensor name. A previously
de-selected sensor will not show an “*” next to the
sensor name.

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7. Press the [MODE] key momentarily to move from one

sensor location to the next one. Repeat Step 7 until all
of the sensors which need to be calibrated during
multiple sensor calibration are selected. Press and hold
the [MODE] key for 1 second to save the new sensor
selection.

8. The display shows “Save?” To confirm the new

selection, press the [Y/+] key to accept the change and
continue on with Step 2. Press the [N/-] key or the

[MODE] key to discard the change and to continue on

with Step 2.

Cross Sensitivity: Some sensors may show cross
sensitivity to other gases. Therefore, it is important to
choose the gas mixture carefully for the multiple sensor
calibration to avoid erroneous calibration due to cross
sensitivity. For example, some VOC gases are known to
cause erroneous readings by the CO sensor. In general, it is
recommended to calibrate the two toxic sensors,
combustible and oxygen sensor with a bottle of mixed gas
using the multiple sensor calibration procedure and to
calibrate the PID sensor with a bottle of a single VOC gas.

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4.4.3 Single Sensor Calibration

This procedure determines the second point of the sensor
calibration curve for a single sensor. A standard reference
gas (span gas) is needed to perform this procedure. Table

2.2 shows the standard calibration gas which is typically
used as the span gas in the factory (connect the tube to the
sampling bag filled with the standard gas as shown in Figure
4-1).

1. Continuing from Step 4 or Step 6 of the previous

section, the display should show “Single Sensor
Calibration?” Press [Y/+] key. The display shows all the
installed sensors in the monitor with the cursor blinking
at the first sensor location. Press [Y/+] key to select the
high-lighted sensor and start the calibration, or press
[MODE] key momentarily to move to the next sensor
location.

TOX1 VOC TOX2

CO VOC H2S
LEL pick? OXY

LEL OXY

2. Turn on the valve of the CO gas bottle to start the flow

of the span gas. Display shows “Apply CO Gas” and will
wait for the calibration gas to reach the sensor. When
the calibration gas has reached the sensor the display
will show “calibration in progress…60” with the
countdown timer shows the number of remaining

seconds while the monitor performs calibration. When

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the countdown timer reaches 0, the display shows the
sensor name and the calibrated value:

TOX1 VOC TOX2

CO cal’ed
reading = 50 ppm

LEL OXY

If no gas has reached the sensor after 60 seconds, the
display will show "No gas flow…” and abort the
calibration.

Note: The reading should be very close to the span gas
value. After about 5 seconds pause, the display will show
the message “Span Cal Done! Turn Off Gas”

3. This completes the single gas calibration procedure for

one sensor. The display shows the single gas calibration
sub-menu for a user to select another sensor or move to
next calibration sub-menu.

4. Turn off the flow of gas. Disconnect the calibration

adapter from the MultiRAE PLUS Monitor.

5. Repeat Step 1 to Step 5 to calibrate the next sensor.

6. Press the [MODE] key any time during Step 2 to reduce

waiting time. If the sensor failed the calibration, the
sensor name and an error message “failed, continue?”
will appear. Press [N/-] or [MODE] key to abort the
calibration and move directly to the next sub-menu item.
Press [Y/+] key to continue single gas calibration. In

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either case, the current calibration data will not be
changed.

Oxygen Sensor Calibration
The oxygen sensor calibration is slightly different from all

other sensors. The oxygen sensor measures a range from 0
to 30% of oxygen in the air. During “fresh” air calibration,
the oxygen sensor is calibrated to fixed 20.9% of oxygen.
During single sensor calibration, the user can supply a pure
nitrogen gas so that the oxygen sensor can be calibrated to
0% of oxygen. The user can also supply other span
concentration of the oxygen, e.g. 19.5%, to calibrate the
oxygen sensor. A question “0% oxygen?” will be asked.
Enter [Y/+] key if the pure nitrogen gas is used to calibrate
the oxygen sensor. Otherwise, enter [N/-] key to calibrate
oxygen sensor to other span oxygen value. During both
single or multiple sensor calibration, the oxygen sensor will
be calibrated to the span value defined in Section 4.4.4.

Note: After a “0% oxygen” calibration, the user must
perform a fresh air calibration to ensure that the
oxygen sensor is calibrated correctly.

Calibration Time Stamp
When a single or multiple sensor calibration is performed, a

time stamp will be stored in the non-volatile memory. This
information will be included in the datalogging report.

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4.4.4 Modify Span Gas Value

This function allows the user to change the span values of
the standard calibration gases.

1. “Modify Span Gas Value?” is the next sub-menu item in

Table 4.3.

2. Press [Y/+] key. Display shows:

TOX1 VOC TOX2

50 100 25
50 span 20.9

LEL OXY

The cursor is blinking at the first digit of the first Span
value. If the user wants to modify any one of the span gas
value, go to Step 3. Otherwise, press and hold the

[MODE] key for 1 second to accept the previously stored

span gas value and move to the next calibration sub­menu.

3. Starting from the left-most digit of the span gas value,

use [Y/+] or [N/-] key to change the digit value and press

[MODE] key momentarily to advance to next digit, the

cursor will move to the next digit to the right. Repeat
this process until all span gas values are entered. Press
and hold the [MODE] for 1 second to save the new
calibration gas value.

4. The display shows “Save?” To confirm the new value

press the [Y/+] key to accept the change. Press the [N/-]
key or the [MODE] key to discard the change and move
to the next calibration sub-menu.

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4.4.5 Change LEL/VOC Span Gas

This function allows the user to select a specific LEL or
VOC gas to be used as the span gas during LEL or VOC gas
calibration.

1. “Change LEL/VOC Span Gas?” is the next sub-menu item

in Table 4.3.

2. Press [Y/+] key. If LEL sensor is installed and enabled,

the display shows:

TOX1 VOC TOX2

LEL Span = ?
methane

LEL OXY

Otherwise, the message “No LEL installed” will appear.

3. If the user does not want to change the LEL span gas,

press [Y/+] key to accept the current selection and exit
this sub-menu.

4. If the user wants to select a different LEL span gas, press

[N/-] key. Then use [Y/+] or [N/-] key to scroll through
a list of gas names until a desired gas name appears in the
LCD display, then press [MODE] key to select the new
gas name.

5. The display shows “Save?” To confirm the new gas

selection, press the [Y/+] key to accept the change. Press
the [N/-] key or the [MODE] key to discard the change
and move to the next display.

6. If the VOC sensor is installed and enabled, the display

shows:

TOX1 VOC TOX2

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VOC Span = ?
isobutylene

LEL OXY

Otherwise, the message “No VOC installed “ will appear.

7. If the user does not want to change the VOC span gas,

press [Y/+] key to accept the current selection and exit
this sub-menu.

8. If the user wants to select a different VOC span gas,

press [N/-] key first then use [Y/+] or [N/-] key to scroll
through a list of gas names until a desired gas name
appears in the LCD display, then press [MODE] key to
select the new gas name.

9. The display shows “Save?” To confirm the new gas, press

the [Y/+] key to accept the change. Press the [N/-] key or
the [MODE] key to discard the change and return to the
first calibration sub-menu.

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4.5 Change Alarm Limits

In the programming mode, the users may change alarm limits
of each sensor for the MultiRAE PLUS Monitor. Table

4.4 shows the sub-menus for changing the alarm limits.
Table 4.4

Alarm Limit Sub-Menu

Change High Alarm limit?
Change Low Alarm limit?
Change STEL alarm limit?

Change Average alarm limit?

1. The sub-menu item in Table 4.4 allows the user to change

the high alarm limit, low alarm limit, STEL alarm limit or
average alarm limit. The average alarm limit can be
“Running Average” or “TWA (Time Weight Average)
depending on the menu selection on “Change Averaging
Method” (see Section 4.7.8). Press [N/-] key to circle
through the sub-menu. Press [Y/+] key to enter a sub­menu and the display shows “HIGH”, “LOW”, “STEL”,
“TWA ” or “AVG” with a flashing cursor on the left-most
digit of the previously stored alarm limits.

TOX1 VOC TOX2

200 100.0 20
20 HIGH 23.5

LEL OXY

TOX1 VOC TOX2

35 50.0 10

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10 LOW 19.5

LEL OXY
TOX1 VOC TOX2

100 25.0 15
STEL

LEL OXY

TOX1 VOC TOX2

35 10.0 10
TWA

LEL OXY

TOX1 VOC TOX2

1.0 10.0 10
AVG

LEL OXY

2. To modify this limit, starting from the left-most digit,

use the [Y/+] or [N/-] key to change the digit value and
press the [MODE] key momentarily to advance to the
next digit. The flashing digit will move on to the next
digit to its right. Repeat this process until all the new
Alarm limits are entered. Press and hold the [MODE]
key for 1 second to exit data entry mode. If there is any
change to the existing value, the display shows “Save ?”
Press the [Y/+] key to ac cept the new value and move to
the next sub-menu. Press the [N/-] key to discard the
changes. To preserve the previously stored alarm limit,
press and hold the [MODE] key for 1 second and the
monitor will exit data entry mode and move to the next
sub-menu.

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4.6 View or Change Datalog

MultiRAE monitor calculates and stores the gas readings at a
specified interval. The user can review these stored readings
or change datalog setup from the programming mode. Users
can also program additional dat alog options in PC and down
loaded them to the monitor (see Section 5.0 for details on
how to program additional datalogging options). Table 4.5
shows the sub-menus for datalog options:

Table 4.5

Datalog Sub-Menu

Reset Peak and Minimum?
Clear All Data?
Change Datalog Period?
Select Data Type?
View Datalog?
Enable / Disable Datalog?

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4.6.1 Reset Peak and Minimum

This function will reset peak and minimum data stored in the
non-volatile data memory.

1. “Reset Peak and Minimum?” is the first sub-menu item

in Table 4.5.

2. Press the [Y/+] key to clear the peak and minimum data

memory. Display shows “Are You Sure?” to re-confirm
whether to reset peak and minimum data.

3. Press the [Y/+] key again will reset peak and minimum

data.

4. Press the [N/-] or [MODE] key to exit without resetting

the data and move to next datalog sub-menu.

Note: STEL and TWA (or AVG) value will not be affected
when peak and minimum values are reset.

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4.6.2 Clear All Data

This function will erase all data stored in the non-volatile
data memory. This does not change STEL, TWA, Peak,
minimum concentration and run time values which are stored
in the other location.

1. “Clear All Data?” is the second sub-menu item in Table

4.5.

2. Press the [Y/+] key to clear the data memory. Display

shows “Are You Sure?” to re-confirm the clearing of
memory.

3. Press the [Y/+] key again will erase all the data memory.

4. Press the [N/-] or [MODE] key to exit without clearing

the data memory and move to next datalog sub-menu.

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4.6.3 Change Datalog Period

The datalog period can be programmed from 1 to 3,600
seconds (1 hour).

1. “Change Datalog Period?” is the third sub-menu item in

Table 4.5.

2. Press the [Y/+] key, the display shows “New Period =

0060” with the left-most digit flashing, where “0060” is
the previously stored datalog period.

3. To modify this period, starting from the left-most digit,

use the [Y/+] or [N/-] key to change the digit value and
press the [MODE] key momentarily to advance to the
next digit. The flashing digit will move to the next digit
to the right. Repeat this process until all 4 digits of the
new period are entered. Press and hold the [MODE] key
for 1 second to exit data entry mode. If there is any
change to the existing value, the display will show
“Save?” Press the [Y/+] key to accept the new value and
exit the datalog sub-menu. Press the [N/-] key to discard
the changes and move to the next menu option.

4. To preserve the previously stored period, press and hold

the [MODE] key for 1 second. The monitor will exit data
entry mode and move to the next sub-menu item in Table

4.5.

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4.6.4 Select Data Type

The user can choose to store either the average or the peak
value during each datalog period.

1. “Select Data Type ?” is the fourth sub-menu item in Table

4.5.

2. Press the [Y/+] key, the display shows the current data

type: “Data Type = Average?”

3. Press the [Y/+] key to accept the currently displayed data

type. Press [N/-] key to change to the other data. type:
“Data Type = Peak?” Press [MODE] key to exit this
sub-menu and move on to the next sub-menu.

4. If there is any change to the existing selection, pressing

the [y/+] key, the display will show “Save?” Then, press
the [Y/+] key to accept or the [N/-] key to discard and
move to the next sub-menu.

Note: It is necessary to select “Average” data type in order

to calculate the correct STEL and TWA data for
datalogging report (see Section 5.9).

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4.6.5 View Datalog

This function allows the user to review all the data that is
stored in the non-volatile data memory.

1. “View Datalog?” is the fifth sub-menu item in Table 4.5.

Press the [Y/+] key and the LCD display shows the first
event number and start date and time of the event.

TOX1 VOC TOX2

Event # 1 ?
8/3/96 8:20

LEL OXY

2. Press [Y/+] key to review data of the first event. The

LCD display shows the stored data of each sensor and the
time stamp:

TOX1 VOC TOX2

1 0.0 0
2 8:20 20.5

LEL OXY

3. Press the [Y/+] or [N/-] key to move forward or backward

to view other data of this event. When reaching the end
or the beginning of the event, the message “Start of data!”
or “End of data!” will appear. Press [MODE] key to exit
the current event.

4. Press [N/-] key at Step 2 to see next event. If there is no

more event, the message “no more event! quit?” will
appear. Press [N/-] key to go back to the first event or
press [Y/+] key to exit and move to the next sub-menu.

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4.6.6 Enable / Disable Datalog

The user can choose to enable or disable the datalogging
function on each individual sensor. This allows users to
selectively log certain sensor readings of interest.

1. “Enable / Disable Datalog?” is the sixth sub-menu item in

Table 4.5.

2. Press [Y/+] key. The display shows all the installed

sensor in the monitor. A previously selected sensor to
be datalogged is marked with an “* ” next to the sensor
name. The cursor is blinking at the first sensor location.
Press [Y/+] key to enable the datalogging for the sensor
and [N/-] key to disable the datalogging.

TOX1 VOC TOX2

CO* VOC H2S*
LEL pick OXY

LEL OXY

3. Press [MODE] key momentarily to move from one

sensor location to the next one. Repeat Step 2 until all
the sensors which needs to be datalogged are selected.
Press and hold [MODE] key for 1 second to save the
new sensor selection.

4. The display shows “Save?” To confirm the new

selection, press the [Y/+] key to accept the change. Press
the [N/-] key or the [MODE] key to discard the change
and return to the first datalog sub-menu.

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4.7 Change Monitor Setup

In the programming mode, users may change monitor setup
or enter user information for the MultiRAE PLUS
monitor. Table 4.6 shows the sub-menus for changing the

monitor.

Table 4.6

Monitor Setup Sub-Menu

Change Site ID?
Change User ID?
Change Alarm Mode?
Change User Mode?
Change Real Time Clock?
Change Backlight Mode?
Change Password?
Change Pump Speed?
Change Averaging Method?

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4.7.1 Change Site ID

The user can enter an 8 digit alphanumeric site ID in the
programming mode. This site ID will be included in the
datalog report.

1. “Change Site ID?” and “Change User ID?” are the first

and second sub-menu item in Table 4.6.

2. Press [MODE] key to choose one of them and press the

[Y/+] key, the display shows the current site ID: “Site ID

= xxxxxxxx” or the current user ID: “User ID =
xxxxxxxx” with the left most digit flashing.

3. Press the [Y/+] or [N/-] key to cycle through all 26

letters and 10 numerals. Press [MODE] key
momentarily to advance to the next digit. The flashing
digit will move to the next digit to the right. Repeat this
process until all 8 digits of the new site ID are entered.

4. Press and hold the [MODE] key for 1 second to exit the

data entry mode and move to the next monitor setup sub­menu.

5. If there is any change to the exi sting site ID, the display

shows “Save?” Press the [Y/+] key to accept the new site
ID and exit the monitor setup sub-menu. Press the [N/-]
key to discard the changes and move to the next sub­menu.

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4.7.2 Change Alarm Mode

There are two different alarm modes: latched and
automatic reset in MultiRAE PLUS that can be selected

from the programming menu.

1. “Change Alarm Mode?” is the third sub-menu item in

Table 4.6.

2. Press the [Y/+] key, the display shows the current alarm

mode selection: “Alarm Mode = Latched?”

3. Press the [Y/+] key to accept the currently displayed

alarm mode. Press [N/-] key to change to the other
alarm mode: “Alarm Mode = Auto Reset?” Press
[MODE] key to exit this sub-menu and move to the next
monitor setup sub-menu.

4. If there is any change to the existing selection, pressing

the [y/+] key the display will show “Save?” Then, press
the [Y/+] key to accept or the [N/-] key to discard and
move to the next sub-menu.

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4.7.3 Change User Mode

There are three different user modes: text, display and
programming in MultiRAE PLUS that can be selected

from the programming menu.

1. “Change User Mode?” is the fourth sub-menu item in

Table 4.6.

2. Press the [Y/+] key, the display shows the current user

mode selection: “User Mode = Program?”

3. Press the [Y/+] key to accept the currently displayed

user mode. Press [N/-] key to scroll through the other
two user modes. Press [MODE] key to exit this sub­menu and move to the next monitor setup sub-menu.

4. If there is any change to the existing selection, pressing

the [y/+] key the display will show “Disable Program!
Are you Sure?” Then, press the [Y/+] key to accept or the

[N/-] key to discard and move to the next sub-menu.

NOTE: If the user mode is changed to display or text

mode, the user can no longer enter the programming menu.
Therefore, the user cannot change the user mode back to

program mode from the monitor. The only way to change
the user mode back to “program” mode is to use a PC
and the ProRAE-Suite program or “multicfg” program

(see Section 5 for details).

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4.7.4 Change Real Time Clock

The MultiRAE monitor is equipped with a real time clock.
The user can enter the correct date and time into the real
time clock in the programming mode.

1. The fifth sub-menu item in Table 4.6 is “Change Real

Time Clock?”

2. Press [Y/+] key, the display shows both the current date

and time : “Date = mm / dd” and “Time = hh : mm” with
the left most digit of the date flashing.

3. To modify this value, use the [Y/+] or [N/-] key to change

the digit value and press the [MODE] key momentarily to
advance to the next digit. The flashing digit will move on
to next digit to its right. Repeat this process until the
new date and time values are entered. Press and hold the

[MODE] key for 1 second to exit data entry mode. If

there is any change to the existing value, the display
shows “Save?” Press the [Y/+] key to accept the new
value and move to next sub-menu. Press the [N/-] key to
discard the changes and move to next sub-menu.

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4.7.5 Change Back Light Mode

The MultiRAE monitor allows a user to choose to turn on
and off LCD back light automatically when ambient light
falls bellow or above a threshold level or to turn on and off
the back light manually by pressing the [N/-] key.

1. The sixth sub-menu item in Table 4.6 is “Change

Backlight Mode?”

2. Press [Y/+] key, the display shows the current back light

mode: “Back Light Mode = manual turn on?”

3. Press the [Y/+] key to accept the currently displayed

back light mode. Press [N/-] key to change to the other
back light mode: “Back Light Mode = manual turn on?”
Press [MODE] key to exit this sub-menu and move to
the first monitor setup sub-menu.

4. If there is any change to the existing selection, pressing

the [Y/+] key the display will show “Save?” Then, press
the [Y/+] key to accept or the [N/-] key to discard and
move to the next sub-menu.

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4.7.6 Change Password

The user can modify the password from the monitor.

1. The seventh sub-menu item in Table 4.6 is “Change

Password?”

2. Press the [Y/+] key and the display shows the current

password: “Enter new password = xxxx” with the left
most digit flashing.

3. Press the [Y/+] or [N/-] key to cycle through all 10

numerals. Press [MODE] key momentarily to advance
to the next digit. The flashing digit will move to the next
digit to the right. Repeat this process until all 4 digits of
the new password are entered.

4. Press and hold the [MODE] key for 1 second to exit the

data entry mode and move to the next monitor setup sub­menu.

5. If there is any change to the existing password, the

display shows “Save ?” Press the [Y/+] key to accept the
new password. Press the [N/-] key to discard the changes
and move to the next sub-menu.

6. The monitor next asks for this value to be confirmed.

“Confirm New Password = 0000” with the left most digit
flashing. The number must be reentered as before to exit
the monitor setup sub-menu. If misentered the second
time, the password reverts to its original setting.

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4.7.7 Change Pump Speed

There are two speed settings for the pump motor in the

MultiRAE PLUS that can be selected from the

programming menu: low (default) and high. The “high”
setting should be used for long lengths of tubing or when
rapid changes in input conditions are expected. “Low” may
be selected when the operating conditions are slow to
change. Low may also be used to prolong pump motor life,
LEL sensor life and battery run time. Note that this screen
may not be present for diffusion models or if speed control
is not available.

1. “Change Pump Motor Speed?” is the eighth sub-menu

item in Table 4.6.

2. Press the [Y/+] key, the display shows the current pump

speed selection: “Pump Speed = Low?”

3. Press the [Y/+] key to accept the currently displayed

pump speed and move to the next monitor setup sub­menu. Press [N/-] key to change to the other speed
“Pump Speed = High?” Press [MODE] key to exit this
sub-menu and move to the next monitor setup sub-menu.

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4.7.8 Change Averaging Method

There are two methods of calculation used in the averaging
of the monitor. Using this selection can cause the
calculation to be performed using an eight hour time
weighted average (TWA), the default, or a running average
(AVG). The display indicator for whichever averaging type
is selected will show on the LCD display wherever the
average is indicated.

1. “Change Averaging Method?” is the ninth sub-menu item

in Table 4.6.

2. Press the [Y/+] key, the display shows the current

average selection: “Average Type = TWA?”

3. Press the [Y/+] key to accept the currently displayed

type. Press [N/-] key to change to the other selection:
“Average Type = Running Average?”, and [Y/+] to select.

4. If there is any change to the existing selection, pressing

the [Y/+] key, the display will show “Save?” Then, press
the [Y/+] key to accept or the [N/-] key to discard and
move to the first setup sub-menu.

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4.8 Change Sensor Configuration

In the programming mode, users may change several sensor
related configurations of the MultiRAE PLUS monitor.
Table 4.7 shows the sub-menus for setting various

configurations of the sensors.

Table 4.7

Sensor Configuration Sub-Menu

Change LEL/VOC Gas Selection?
Enable / Disable Sensors?
Change Dilution Ratio?
Change PID Lamp Type?

Before these sub-menus are described, the term “Correction
Factor” needs to be explained:

Correction Factor

The PID and LEL sensor used in MultiRAE PLUS are
broad band sensors (i.e., they respond to a broad range of
gases). Typically, these sensors show a different sensitivity
to different gases. The correction factor for a specific gas
is defined as:

Sensitivity to a calibration gas
Correction Factor =

________________________

Sensitivity to a specific gas

Correction factors are often used to obtain a calculated
concentration of a specific gas while using a different gas
during calibration.

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The MultiRAE PLUS monitor store three sets of correction
factors: one for the LEL sensor, one for the 10.6 eV PID
sensor and the other for the 11.7 eV PID sensor. Each set
consists of 20 to 40 different gases. The user can choose
one gas from the list to be the calibration gas and another
gas to be the measurement gas.

For example, the user can choose methane as the calibration
gas for the LEL sensor and select pentane as the
measurement gas. The MultiRAE PLUS monitor will
calculate the correction factor between these two gases and
convert the measured value of the LEL sensor into
equivalent concentration of the pentane gas.

Similarly, the user can choose one VOC gas for calibration
and choose another VOC gas for measurement. In addition,
the correction factor is different for the PID sensor due to
different energy of the UV lamp used in the PID sensor. The
user needs to choose the correct type of UV lamp (10.6 eV
or 11.7 eV) for the PID sensor in Section 4.8.4.

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4.8.1 Change LEL/VOC Gas Selection

This function allows users to choose one of the pre-stored
LEL or VOC gases in the monitor and calculate its
correction factor relative to the LEL or VOC calibration gas.
This factor will then be used during gas measurements to
show the equivalent concentration of the selected LEL or
VOC gas. The user can also modify this relative correction
factor to increase or decrease the gas reading. This allows
users to create a custom factor for a specific gas or mixture
of gases.

1. “Change LEL/VOC Gas Selection?” is the first sub-menu

item in Table 4.7.

2. Press [Y/+] key. If an LEL sensor is installed and

enabled, the display shows:

TOX1 VOC TOX2

LEL Gas = ?
methane

LEL OXY

Otherwise, the message “No LEL installed” will be
displayed and skip to Step 8.

3. If the user does not want to change the LEL measurement

gas, press [Y/+] key to accept the cur rent gas and skip to
Step 6.

4. If the user wants to modify the LEL measurement gas,

press [N/-] key first, then use [Y/+] or [N/-] key to
scroll through a list of gas names until the desired gas
name appears in the LCD display, then press [MODE]
key to select the new gas name.

PROGRAMMING OF MULTIRAE

4 - 41

5. The display shows “Save new gas ?”. To confirm the new

gas, press the [Y/+] key to accept the change. Press the

[N/-] key or the [MODE] key to discard the change and

move to the next step.

6. Display shows

TOX1 VOC TOX2

methane
LELFactor=1.00 ?

LEL OXY

where “1.00” is the calculated correction factor of the

selected gas in Step 4.

7. If the user does not want to modify the LEL correction

factor, press [Y/+] key and go to Step 8. To modify this
factor, press [N/-] key first. Then starting from the left­most digit, use the [Y/+] or [N/-] key to change the digit
value and press the [MODE] key momentarily to advance
to the next digit. The flashing digit will move on to next
digit to its right. Repeat this process until all 4 digits of
the new factor are entered. Press and hold the [MODE]
key for 1 second to exit data entry mode. If there is any
change to the existing value, the display shows “Save ?”
Press the [Y/+] key to accept the new value and exit the
gas selection sub-menu. Press the [N/-] key to discard
the changes.

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8. If the VOC sensor is installed and enabled, the display

will show:

TOX1 VOC TOX2

VOC Gas = ?
isobutylene

LEL OXY

Otherwise, the message “No VOC installed” will be
displayed and move to the next sub-menu.

9. If the user does not want to change the VOC

measurement gas, press [Y/+] key to accept the current
gas and go to Step 12.

10. If the user wants to modify the VOC measurement gas,

press [N/-] key first, then use [Y/+] or [N/-] key to
scroll through a list of gas names until the desired gas
name appears in the LCD display, then press [MODE]
key to select the new gas name.

11. The display shows “Save?” To confirm the new gas, press

the [Y/+] key to accept the change. Press the [N/-] key or
the [MODE] key to discard the change and move to the
next step.

12. Display shows

TOX1 VOC TOX2

isobutylene
VOCFactor=1.00 ?

LEL OXY

where “1.00” is the calculated correction factor of the

selected gas in Step 10.

PROGRAMMING OF MULTIRAE

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13. If the user does not want to modify the VOC correction

factor, press [Y/+] key and exit the sub-menu. To
modify this factor, press [N/-] key first. Then starting
from the left-most digit, use the [Y/+] or [N/-] key to
change the digit value and press the [MODE] key
momentarily to advance to the next digit. The flashing
digit will move on to next digit to its right. Repeat this
process until all 4 digits of the new factor are entered.
Press and hold the [MODE] key for 1 second to exit data
entry mode. If there is any change to the existing value,
the display shows “Save ?” Press the [Y/+] key to accept
the new value and exit the gas selection sub-menu. Press
the [N/-] key to discard the changes.

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4.8.2 Enable / Disable Sensor

This function allows the user to selectively enable or disable
individual sensors in the MultiRAE PLUS monitor. When
a sensor is disabled, the sensor will not measure nor display

the gas concentration.

1. “Enable / Disable Sensors?” is the second sub-menu item

in Table 4.7.

2. Press [Y/+] key. The display shows all the installed

sensors in the monitor. A previously enabled sensor is
marked by an “*’ next to the sensor name. The cursor
will blink at the first sensor location. Press [Y/+] key to
enable the sensor and [N/-] key to disable the sensor. A
previously disabled sensor will show “----” instead of the
sensor name.

TOX1 VOC TOX2

CO* VOC H2S*
LEL* pick OXY*

LEL OXY

3. Press [MODE] key momentarily to move from one

sensor location to the next one. Repeat Step 2 until all
the sensors which needs to be enabled are selected.
Press and hold [MODE] key for 1 second to save the
new sensor selection.

4. The display shows “Save?” To confirm the new selection,

press the [Y/+] key to accept the change. Press the [N/-]
key or the [MODE] key to discard the change and move
to the next sub-menu.

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4.8.3 Change Dilution Ratio

The user can insert an optional dilution fitting on the

MultiRAE PLUS gas inlet port to dilute the gas sample.

The user can enter a dilution ratio (from 1 to 10) from the
programming menu so that the reading can be compensated
to show the actual concentration of the gas sample with the
dilution fitting.

1. “Change Dilution Ratio?” is the third sub-menu item in

Table 4.7.

2. Press the [Y/+] key, the display shows the current

dilution ratio: “Dilution Ratio = xx” with the left most
digit flashing.

3. Press the [Y/+] or [N/-] key to increase or decrease the

value of the digit. Press [MODE] key momentarily to
advance to the next digit. The flashing digit will move to
the next digit to the right. Repeat this process until both
digits of the new dilution ratio are entered.

4. Press and hold the [MODE] key for 1 second to exit the

data entry mode and move to the next sub-menu.

5. If there is any change to the existing dilution ratio, the

display shows “Save ?” Press the [Y/+] key to accept the
new ratio and exit the sub-menu. Press the [N/-] key to
discard the changes and move to the next sub-menu.

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4.8.4 Change PID Lamp Type

This programming menu only applies to the monitor which is
equipped with a PID detector option. There are two
different energy UV lamps available for the PID sensor:

10.6 eV and 11.7 eV. The user can select either lamp from
the programming menu.

1. “Change PID Lamp Type?” is the fourth sub-menu item in

Table 4.7.

2. Press the [Y/+] key, the display shows the current PID

lamp selection: “PID Lamp = 10.6 eV?”

3. Press the [Y/+] key to accept the currently displayed PID

lamp. Press [N/-] key to change to the other lamp. Press
[MODE] key to exit this sub-menu and return to the first
sub-menu.

4. If there is any change to the existing selection, pressing

the [Y/+] key the display will show “Save?” Then, press
the [Y/+] key to accept the [N/-] key to discard and return
to the first sub-menu.

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4 - 47

4.9 Exit Programming Mode

1. To exit programming mode from the first tier menu level

(see Table 4.1), press the [MODE] key once.

Display shows an instantaneous reading of normal

operation mode.

2. To exit programming mode from 2nd tier sub-menu level

(see Table 4.2 - 4.6), press the [MODE] key twice.

3. To return to programming mode, press and hold down

both the [MODE] and [N/-] keys for 3 seconds as
described in Section 4.4.

COMPUTER INTERFACE FOR MULTIRAE PLUS

5 - 1

5. COMPUTER INTERFACE FOR

MULTIRAE PLUS

Each MultiRAE PLUS with a datalogging option is shipped
with a software package, called ProRAE-Suite, and a serial
computer interface cable.

This software package runs on any IBM compatible Personal
Computer (PC) under Windows 95, Windows 98,
Windows NT 4.0 and later environments. It allows the user
to configure the MultiRAE PLUS through a user friendly
interface and send the configuration information from the
PC to the MultiRAE PLUS monitor. Collected data can also
be extracted from the MultiRAE PLUS to the PC in order to
perform data analysis, report generation or record keeping.
Installation and operation of this software package is
described in the following sections.

COMPUTER INTERFACE FOR MULTIRAE PLUS

5 - 2

5.1 Install ProRAE -Suite Software

ProRAE-Suite software package is supplied with the
MultiRAE PLUS datalogging monitor. This software
package is available on two 3.5” setup diskettes. To install
the ProRAE-Suite software, insert the first setup diskette
into the “A” or “B” floppy disk drive. Click the Start button
on the taskbar to display the start menu, then click the Run
from the start menu to display the Run dialog box. If the
setup diskette is in disk drive A, type A:\Setup.exe in the
Open field, as shown in Figure 5-1.

Figure 5-1 Run Dialog Box

Press the Enter key on the keyboard or click the OK button
on the menu to start the setup process. If the user choose
the default settings in every steps of the process, the
ProRAE-Suite software package will be installed under the
default directory: C:\Program Files\RAE Systems
Inc\ProRAE-Suite. After the software is installed
successfully, a new menu item ProRAE-Suite is added to
the Programs menu. To start the ProRAE -Suite software,

COMPUTER INTERFACE FOR MULTIRAE PLUS

5 - 3

click the Start button on the taskbar to display the Start
menu, click the Programs menu item to display the
Programs submenu, then click the ProRAE-Suite menu
item to display the ProRAE-Suite submenu. There are two
submenu items under the ProRAE-Suite submenu:
ProRAE-Suite and Readme, as shown in Figure 5-2. Click
the ProRAE-Suite submenu item to start the ProRAE-Suite

software.

Figure 5-2 Start Menu

COMPUTER INTERFACE FOR MULTIRAE PLUS

5 - 4

5.2 Connect MultiRAE PLUS to PC

The basic kit of a MultiRAE PLUS datalogging monitor
includes a serial interface cable. Connect the DB-9
connector side of the cable to the serial port of the PC, and
connect another side of the cable to the MultiRAE PLUS
monitor.

Turn on the power to the MultiRAE PLUS monitor. Press
the [MODE] key several times until the LCD shows
“Communicate with PC?” Press the [Y/+] key and the display
shows “Monitor will Pause, OK?” Press [Y/+] key to
confirm and the display shows “Ready...” to indicate that the
MultiRAE PLUS monitor is ready for communication with
PC. During the communication session, the PC will directly
control the MultiRAE PLUS monitor through the serial link.
There is no need for users to press any key on the MultiRAE
PLUS monitor during the communication session.

If no data transfer has occurred within one minute, the
MultiRAE PLUS monitor will return to instantaneous
reading display.

Note: Do not connect to the parallel port of the PC by
mistake. The parallel port is usually a 25 pin female D
connector on the back of the PC, the serial port is usually a
25 or 9 pin male D connector. If the serial port on the PC
is a 25 pin connector, the user needs to use a 25 pin to 9 pin
adapter in order to accept the serial cable.

5.3 Start ProRAE -Suite Software