Portable Area Gas Monitor (PAGM) with
Infrared Sensor for N2O Gas
Instruction 3015-4787
Operation & Maintenance
Rev. 8 – February 2013
Product Leadership • Training • Service • Reliability
Page 2
WARRANTY
Bacharach, Inc. warrants to Buyer that at the time of delivery this Product will be free from defects in material and
manufacture and will conform substantially to Bacharach Inc.'s applicable specifications. Bacharach's liability and Buyer's
remedy under this warranty are limited to the repair or replacement, at Bacharach's option, of this Product or parts thereof
returned to Seller at the factory of manufacture and shown to Bacharach Inc.'s reasonable satisfaction to have been
defective; provided that written notice of the defect shall have been given by Buyer to Bacharach Inc. within two (2) years
after the date of delivery of this Product by Bacharach, Inc.
Bacharach, Inc. warrants to Buyer that it will convey good title to this Product. Bacharach's liability and Buyer's remedy
under this warranty of title are li mited to the r emoval of any title defects or, at the election of Bacharach, to the
replacement of this Product or parts thereof that are defective in title.
The warranty set for th in par a gr a ph 1 does not apply to parts the Operating Instructions designate as having a limited shelflife or as being expended in normal use (e.g., filters).
THE FOREGOING WARRANTIES ARE EXCLUSIVE AND ARE GIVEN AND ACCEPTED IN LIEU OF (I) ANY
AND ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE: AND (II) ANY
OBLIGATION, LIABILITY, RIGHT, CLAIM OR REMEDY IN CONTRACT OR T ORT, WHETHER OR NOT
ARISING FROM BACHARACH'S NEGLIGENCE, ACTUAL OR IMPLIED. The remedies of the Buyer shall be limited
to those provided herein to the exclusion of any and all other remedies including, without limitation incidental or
consequential damages. No agreement varying o r extending the foregoing warr a nties, remedies or this limitation will be
binding upon Bacharach, Inc. unless in writing, signed by a duly authorized office r of Bachara ch.
Register Your Warranty by Visiting
www.mybacharach.com
Product improvements and enhancements are continuous; therefore the specifications and information
contained in this document may change without notice.
Bacharach, Inc. shall not be liable for errors contained herein or for incidental or consequential damages in
connection with the furnishing, performance, or use of this material.
No part of this document may be photocopied, reproduced, or translated to another language without the pr ior
written consent of Bacharach, Inc.
Part Number ............................................................................................................................... 24
5.2 Service Centers .............................................................................................................................. 25
6 DECLARATION OF CONFORMITY ....................................................................................................... 26
iv Instruction 3015-4787
Page 5
N2O Portable Monitor Introduction
1 Introduction
1.1 How to Use This Manual
This manual provides important information on how to operate and service Bacharach’s Nitrous Oxide
O) Portable Monitor.
(N
2
To assure operator safety and the proper use of the monitor, please read, understand, and follow the
contents of this manual.
If you have a working knowledge of gas monitors, you will find this manual useful as a reference tool. If
you are new to the use of gas monitors, you can educate yourself about the principles of gas detection and
the proper operation of this device by reading this manual thoroughly.
1.2 Warning Statements
The use of the word WARNING in this manual denotes a potential hazard associated with the use of this
equipment. It calls attention to a procedure, practice, or condition, or the like, which if not correctly
performed or adhered to, could result in personal injury or death.
1.3 Caution Statements
The use of the word CAUTION in this manual denotes a potential hazard associated with the use of this
equipment. It calls attention to a procedure, practice, condition, or the like, which if not correctly
performed or adhered to, could result in damage to the equipment.
1.4 Hazard Symbols on Monitor
This symbol indicates the need to consult this operating instruction
manual when opening the enclosure.
WARNING: A potential risk exists if the operating instructions are
not followed.
This symbol indicates the presence of electric shock hazards when
the enclosure is opened.
WARNING: To avoid risk of injury from electric shock, do not open
the enclosure when power is applied.
1.5 Safety Precautions
1.5.1 Hazardous Area Warning
Hazardous Area Warning: This instrument has not been
designed to be intrinsically safe for use in areas classified as
hazardous locations. For your safety, DO NOT use it in hazardous
(classified) locations.
Instruction 3015-4787 1
Page 6
Introduction N2O Portable Monitor
Item
Qty.
Part Number
N2O Portable Monitor
1
3015-4790
External Filter Assembly
1
3015-5324
Soft Carrying Case with
Shoulder Strap
Battery Pack & Charger
1
3015-5739
Stainless Steel Probe
1
3015-5326
Instruction Manual
1
3015-4787
Elbow
1
3015-3234
Tubing (3 ft)
1
0003-6182
1.5.2 Combustible/Flammable Gas Warning
Combustible/Flammable Gas Warning: This is NOT a safety
device. Some gases which this instrument can detect may be
combustible/ flammable. When properly configured, this instrument
is designed to alarm at concentrations that are lower than the
explosive limit of the gas. As such, it is the buyer’s responsibility to
initiate an immediate planned response to any gas leaks as soon as
they are detected. This equipment should NEVER be used to
measure or sample gases at or above their respective lower explosive
limits.
1.5.3 Explosive Atmosphere
Explosive Atmosphere: Do not operate this equipment in the
presence of flammable liquids, vapors or aerosols. Operation of any
electrical equipment in such an environment constitutes a safety
hazard.
1.5.4 Misuse and Modifications t o Monitor
The protection provided by the monitor may be impaired if the monitor is used in a manner not specified
by these instructions. Changes or modifications to this monitor will void the warranty.
1.5.5 Altitude Limit
6,562 ft (2,000 m)
1.5.6 Cleaning
Clean the outside of the monitor’s case using a dry cloth — DO NOT use soap and water.
1.6 Unpacking and Initial Checks
Your N2O Portable Monitor was carefully inspected at the factory before shipment, and packed so as to be
highly resistant to damage while in transport. When you receive the instrument, however, please unpack
it promptly and make a visual inspection to make sure that no damage has occurred during shipment. Also
check that all the following items have been received.
1 3015-5700
If damage was found, immediately file a claim with the carrier. If an item is missing, please contact
Bacharach’s Service Department for assistance (refer to Section 5.2Service Centers).
2 Instruction 3015-4787
Page 7
N2O Portable Monitor Introduction
1.7 Shipping Precaution
When shipping the instrument by air, deflate the purge-air bag to prevent it from bursting due to changes
in air pressure. Deflate the bag by selecting the EMTYBAG function as described on page 11.
1.8 Features and Capabilities
• Detects, measures, and displays the level of N
• Measurement range of 0–1,000 ppm with a resolution of 1 ppm
• Self contained purge-air bag, allowing the monitor to be used in a contaminated atmosphere
• Automatically logs up to 200 gas readings that can be printed / plotted for analysis
• Eliminates false alarms with use of non-dispersive IR source and sample draw system
• Visual and audible gas alarm indictors that are turned ON when the detected gas level exceeds
a user defined trip-point
• Extensive self diagnostics, providing both visual and audible indications when a fault occurs
• Battery powered, providing 8–12 hours of operation
O gas in the area being monitored
2
1.9 Functional Overview
The Bacharach Nitrous Oxide (N2O) Portable Monitor is designed to detect, measure, and display the
concentration of N
self-zeros every 4 minutes using its internal supply of fresh air.
During normal operation the N
detected on its front panel LCD. The monitor retains a log of previous readings that can be easily accessed
at a later time for analysis.
Front panel indicators and an audible alarm are provided to signal gas alarm and instrument fault
conditions. The audible alarm can temporarily be silenced by a push of a button, but will reactivate if the
gas level is still above the alarm trip point after a user-defined time period has elapsed.
O gas in the area being monitored. To ensure accurate gas measurements, the monitor
2
O Monitor displays both the current gas level and the peak gas level
2
The N
The monitor incorporates active diagnostics that continuously check the system for proper operation. A
front panel indicator is provided to alert an operator of system malfunctions, and fault codes are generated
that enable the operator to quickly identify the cause of the fault.
O Monitor requires only minor periodic maintenance such as the occasional replacement of filters.
2
Instruction 3015-4787 3
Page 8
Specifications N2O Portable Monitor
2 Specifications
Product Type ..................... Portable N2O Gas Monitor
Accuracy ............................ ±1 ppm ±5% of reading from 0 to 100ppm
and ±10% of reading from 101 to 1000ppm.
Response Time .................. 90% of response within 3 seconds; 100% in 5 seconds
Temperature Drift ............ 1.5 ppm per °C between purge cycles
System Noise .................... Less than 40dB(A) at 10 ft (3 m)
Operating Temp................ 32 to 122°F (0 to 50°C)
Ambient Humidity ........... 5 to 90% RH (non-condensing)
Altitude Limit ................... 6,562 ft (2,000 m)
Power ................................. DC power pack, provides 8–12 hours of operation
Power Consumption ......... 15 Watts
Front Panel ....................... 3 Indicator lights:
ON – Green LED flashes during warm-up, and then glows steady
during normal operation
FAULT – Yellow LED flashes when there is a system fault
ALARM – Red LED flashes when the gas level is above its alarm setting
Audible Alarm .................. Internal audible alarm programmable for any of the following conditions:
OFF, FAULT/ALARM, ALARM
Dimensions ....................... 9D x 14.5L x 5W inches (229 x 368 x 127 mm)
Weight ............................... Less than 9 lbs (4 kg) including battery
Valid Calibration Period
to Specifications ................ 12 months
Warranty ........................... 2 Years from date of shipment
4Instruction 3015-4787
Page 9
N2O Portable Monitor Operation
3 Operation
3.1 Front Panel Display and Controls
3.2 Connecting Ga s -Sample & Exhaust Lines
3.2.1 Overview
A single gas-sample line needs to be run from the N2O Monitor to the area to be monitored. If desired, an
optional exhaust line can be installed to vent N
3.2.2 Connecting the Gas-Sampl e Line
To connect the gas-sample line to the monitor, simply push the tubing onto the elbow connector and attach
the elbow onto the Gas Sample Port on the front of the monitor as shown in the illustration below.
The gas-sample line can be up to 50 ft (15.2 m) in length. All tubing bends should have a radius of no less
than 5" to insure proper airflow. If kinks or obstructions occur in the line the monitor may not function
properly.
The end of this line should be placed near the potential leak source and positioned to reduce the possibility
of mists, aerosols, oil, water, dust, or other contaminates being drawn into the monitor.
An external filter (P/N 3015-5324) should be attached to the end of this line. See figure below.
Instruction 3015-4787 5
O gas away from the monitor.
2
Page 10
Operation N2O Portable Monitor
To connect the exhaust line to the exhaust
BACHARACH
PRESS ENTER FOR
3.2.3 Connecting the Exhaust Line (optional)
The optional exhaust line carries the exhausted gas sample away from the monitor.
The exhaust line can be up to 50 ft (15.2 m) in length. Ideally this line should terminate outdoors in a
location that is not exposed to the elements.
Connect the exhaust line to the monitor by firmly pushing the tubing into the Exhaust Port’s push-toconnect (PTC) fitting. If the exhaust line terminates outside the building, position the tubing so that no
water or moisture can enter the line. Note that this line does not require a termination filter.
port’s PTC fitting, firmly push the appropriate
tubing into the hole in the center of the
connector until it seats in the connector. Refer
to the figures at the left.
To remove tubing from a PTC connector, push
and hold the spring-l oad ed c ollar in war ds, then
simultaneously withdraw the tubing. Refer to
the figures at the right.
3.3 Gas Detector Operation
Turn ON the monitor as follows:
6Instruction 3015-4787
CAUTION: Operate the monitor in its horizontal position (handle facing upwards).
Tilting the monitor to a vertical position while in operation may cause inaccurate
measurements to occur.
1. Lift up the shield located in front of the handle
2. Press the red power ON/OFF toggle switch.
3. Observe monitor’s firmware version is briefly displayed.
VERSION x.xx
NEW TWA/twa
Page 11
N2O Portable Monitor Operation
MEASURE 2ndUNIT
PURGE 2ndUNIT
PURGE AIR EMPTY
PURGE AIR EMPTY
WARM UP
4. Observe that the NEW TWA/twa screen may appear, depending on
the configuration of the monitor’s TWA/twa function (refer to
Section 3.4 for detailed TWA operation).
5. Observe the monitor starts counting down its warm-up period of
900 seconds (15 minutes).
6. At the end of warm up, take the monitor to an area than contains
fresh air and press the ENTER button to fill the monitor’s internal
purge-air bag with clean, fresh air that is of the same temperature
and humidity as the area being monitored for gas. DO NOT fill the
purge-air bag in an area that is contaminated with N
O gas.
2
After the purge-air bag is filled, observe the following as the monitor makes
gas measurements in the area being sampled:
•MEASURE indicates when the monitor is actively measuring the
level of N
O gas at the sampling point. The screen to the right shows
2
that currently 100 ppm is being measured. The measurement cycle
runs for 4 minutes.
A log of up to 200 previous measurements can be viewed using the
PPM LOG function (page 12), or printed as described in 3.15.
The 2ndUNIT value (Blank, Peak PPM, Continuous TWA, or 8 Hr
TWA) is user-selected (refer to 2ndUNIT function on page 13).
•PURGE indicates when the monitor is resetting its infrared detector
to a baseline of 0 ppm using the air contained in the monitor’s
internal purge-air bag. The purge cycle runs for 10 seconds.
The monitor will operate for approximately 40 minutes before the purge-air bag needs refilled.
When the message "PURGE AIR EMPTY" appears, take the monitor to a clean, fresh-air environment and press the ENTER button to refill the bag.
900
(ENTER) TO FILL
100ppm N2O
100ppm N2O
<ENTER> TO FILL
Work with gas alarms and system faults as follows:
ALARM (red) light turns ON if the detected gas level exceeds a programmed alarm point. An audible
alarm also sounds if the AUDALRM function is activated (page 11) Pressing the front panel
SILENCE button turns OFF the audible alarm, but the ALARM light will continue to flash for as
long as the detected gas level is above the alarm point. The audible alarm will reactivate if the gasalarm condition is not cleared within the time period set by the SILENCE function (page 12).
FAULT (yellow) light turns ON if a fault occurs (see Fault Code list on page 15). An audible alarm
also sounds if the AUDALRM function is activated (page 11). Pressing the front panel SILENCE
button turns OFF the audible alarm, but the FAULT light continues to flash for as long as the fault is
present. The audible alarm will reactivate if the fault condition is not cleared within the time period
set by the SILENCE function (page 12). Both the FAULT light and audible alarm will automatically
turn OFF after the cause of the fault has been eliminated. A log of the last 30 fault events can be
viewed using the monitor’s FAULTS function (page 12).
Instruction 3015-4787 7
Page 12
Operation N2O Portable Monitor
PURGE 00TWA
PURGE 00twa
PRESS ENTER FOR
ELAPSED TWA TIME
3.4 Time Weighted Average (TWA) Operation
3.4.1 Overview
In addition to displaying the current N2O level, the monitor can also calculate and display a Time
Weighted Average ppm value. This value is available in two formats (8 Hour or Continuous). This provides
users with the most appropriate data on their average ppm N
TWA operation is selected by using the 2ndUNIT function (page 13).
The two TWA formats are identified by the appearance of either “TWA” or ‘twa” in the upper-right corner
of the Data Display screen.
•TWA (upper case letters) is calculated over an 8-hour period. This format is designed to show the
user’s average ppm N
asterisk (*) will be displayed but the TWA will continue to be updated.
O exposure level during a typical work day. After 8 hours has expired, an
2
O exposure in the working environment.
2
100ppm N2O
•twa (lower case letters) is continuously calculated over the operating time of the monitor. This
mode is useful for monitoring an area for a few minutes or more and is the preferred mode of
operation for checking operating room atmospheres.
100ppm N2O
3.4.2 Starting a New or Continuing TWA/twa
When the monitor is turned ON the following message appears if the monitor is set up to display
TWA/twa.
Press either . . .
NEW TWA/twa
• ENTER to start a new TWA/twa
• ESC to continue with the current TWA/twa.
Tip: If NO button is pressed within 60 seconds the monitor automatically continues
with the current TWA/twa.
Note: During the time the monitor is OFF, the gas measurement is assumed to be zero
and will be factored into the TWA/twa calculation.
After selecting whether to start or continue a TWA/twa, the next screen shows the current elapsed
TWA/twa time.
IS xx MINUTES
Where: xx is the accumulated time used by the monitor in calculating the TWA/twa.
8 Instruction 3015-4787
Page 13
N2O Portable Monitor Operation
PURGE 500pk
STAND BY
PURGE AIR EMPTY
RECHARGING PURGE
3.5 Peak Reading Operation
In addition to displaying the current N2O level, the monitor can also be set up to display its peak ppm
measurement.
The peak reading display is selected by using the 2ndUNIT function (page 13).
100ppm N2O
The display above shows that currently the monitor is detecting 100 ppm N
measurement of 500 ppm has occurred.
The peak reading is reset by pressing the ENTER button.
O and that a peak
2
3.6 Leak Detector Operation
The monitor can be configured to operate as a Leak Detector by setting the AUDALRM function (page 11)
to LEAK DETECTOR.
When configured as a Leak Detector, the monitor will produce a leak detector type of audible feedback. At
zero ppm there will be a tic every 2 seconds with the tic rate increasing up to 20 tics/second when the ppm
level reaches the ALRMLVL (page 11) setting.
3.7 Standby Mode
After becoming operational, the monitor can be placed into a Standby Mode. When taken out of standby
the monitor is ready for operation without waiting an additional 15 minutes to warm up. While in standby
the monitor will stop taking gas samples and stops purging itself from the purge-air bag.
Place the monitor into its Standby Mode by pressing both the ENTER and ESC buttons at the same time.
Take the monitor out of standby by again pressing both the ENTER and ESC buttons.
When the monitor is taken out of standby the operator must refill the purge-air bag by pressing the
ENTER button. Refilling the bag after coming out of standby re-establishes the monitor’s ambient
pressure reading and ensures that the purge-air bag is filled at the start of taking gas measurements.
WARNING: Fill the purge-air bag in a clean, fresh-air environment that is at the
same temperature and humidity as the area being checked for gas. DO NOT fill the
bag in an area that is contaminated with N
.
<ENTER> TO FILL
AIR...
O gas.
2
As soon as the purge-air bag has been refilled with fresh air, the Data Display screen appears and the
monitor resumes normal operation.
Instruction 3015-4787 9
Page 14
Operation N2O Portable Monitor
BACHARACH
WARM UP
MEASURE 2ndUNIT
100ppm N2O
PURGE 2ndUNIT
100ppm N2O
PURGE AIR EMPTY
RECHARGING PURGE
3.8 Battery – Charging and Using
3.8.1 Charging the Battery
The monitor is powered b y a rechargeable batter y pack located in a pouch on the side of the m onitor’s soft
carrying case. The battery pack can be recharged at any time, regardless of the battery’s current charge state.
The AC adapter provided acc epts voltage inputs of 100 to 240 VAC. Plu g the adapter into the wall, then into
the battery. Discon nect the adapter when the batter y is fully charged. A fully charged battery pack will power
the monitor for approximately 8-12 hours.
3.8.2 Using the Battery
The PAGM is designed for a 16VDC input. Following the instructions for the par ticular battery in use, set t he
output voltage to 16V. Plug the batter y into the instru ment's battery input port and the instrum ent is re ady f or
use.
3.9 Display Screen s
3.9.1 Initial Power ON
When the monitor is first powered ON, all front panel lights turn ON and a splash screen appears showing
the monitor’s current firmware revision level. After a brief moment the Warm Up screen is displayed
along with the front panel ON light (green) blinking.
The monitor requires 15 minutes to warm up from a cold start; after which, the ON light glows steady and
the Data Display screen appears.
If the monitor is turned OFF and then turned back ON, the latter warm-up time may be less than
15 minutes depending on the temperature of the IR detector.
VERSION x.xx
3.9.2 Filling the Purge-Air Bag
CAUTION: Fill the purge-air bag in a clean, fresh-air environment that is at the
same temperature and humidity as the area being checked for gas. DO NOT fill the
bag in an area that is contaminated with N
The following message is displayed and an audible alarm is sounded when the monitor’s purge-air bag is
empty. This message appears immediately after warm-up, and approximately every 40 minutes during
normal operation. Press the ENTER button to start the refill process.
<ENTER> TO FILL
After the air bag has been filled, the monitor starts or resumes normal operation by displaying the
Data Display screen.
AIR...
O gas.
2
3.9.3 Data Display Screen
10 Instruction 3015-4787
Page 15
N2O Portable Monitor Operation
>FILLBAG EMTYBAG
ALRMLVL AUDALRM
>PPM LOG LOG INT
FAULTS DIAG
>SILENCE P-CHK
FILLING BAG...
DRAINING BAG...
AUDIBLE ALARM IS
EDIT ALARM LEVEL
>2ndUNIT PRINT
PLOT PC-DUMP
During normal operation the Data Display screen shows when the monitor is performing the following
two functions:
MEASURE indicates that the monitor is actively measuring gas. In the screen shown above the monitor is
currently detecting 100 ppm of N
8 Hr TWA) is user-selected (refer to 2ndUNIT function on page 13). The measurement cycle runs for
4 minutes.
PURGE is displayed when the monitor is resetting its infrared detector to a baseline of 0 ppm using the
fresh air in the monitor’s internal purge-air bag. The purge cycle runs for 10 seconds.
O gas. The 2ndUNIT value (Blank, Peak PPM, Continuous TWA, or
2
3.9.4 Function Screens
The Function screens are used to set up the monitor and display stored data.
From the Data Display screen, press both the Keypad Left and Right buttons at the same time to
display the first Function Menu screen. Next, use the Keypad buttons to move the arrow (>) until it
points to the desired function, and then press the ENTER button to select that function.
Once a function has been selected, use the Keypad to scroll through the displayed data or to change a
parameter associated with that function. Press ENTER to save any newly entered parameters. Press the
ESC button to return to the previous screen without saving.
Note that if no buttons are pressed within 90 seconds after selecting a function, the unit returns to the
Data Display screen.
GAS CLOCK
FILLBAG – Press ENTER to manually fill the purge-air bag.
WARNING: Fill the purge-air bag in a clean, fresh-air environment
that is at the same temperature and humidity as the area being
checked for gas. DO NOT fill the bag in an area that is
contaminated with N
O gas.
2
EMTYBAG – Press ENTER to manually empty the purge-air bag. Use
this function to drain the bag if it becomes contaminated with gas.
ALRMLVL – Detected gas level that causes the front panel ALARM
(red) light to turn ON and the audible alarm to sound (if AUDALRM
function is set to ALARM or ALARM/FAULT).
AUDALRM – The internal audible alarm is programmable to function as
follows:
• OFF – Audible alarm is disabled.
• ALARM – Alarm sounds when detected gas level exceeds the ALRMLVL level as evidenced by the front
panel ALARM (red) light turning ON.
Instruction 3015-4787 11
0300 ppm
ALARM
Page 16
Operation N2O Portable Monitor
#025 7PPM @
LOG INTERVAL IS
4.2159v <0000>
SILENCE TIMEOUT
#15 <1000> @
•ALARM/FAULT – Alarm sounds when either the detected gas level exceeds the ALRMLVL value, or if
a system fault occurs, as evidenced by the front panel ALARM (red) light or FAULT (yellow) light
turning ON.
•LEAK DETECTOR – When selected, the monitor will produce a leak detector type of audible feedback.
At zero ppm there will be a tic every 2 seconds with the tic rate increasing up to 20 tics/second when the
ppm level reaches the ALRMLVL setting.
• TWA ALARM – Audible alarm sounds when the TWA or twa, whichever is selected by the 2ndUNIT
Function, exceeds the ALARMLVL value.
The audible alarm can be temporarily silenced by pressing the SILENCE button (page 12).
PPM LOG – Contains records of the last 200 measurements. Each
record shows the measurement’s date, time, and ppm level.
Measurements are logged at an interval determined by the LOG INT
function. After all 200 locations are filled the newest entries overwrite
the oldest entries.
Use the KeypadUp and Down buttons to change the record number by
a factor of 1. Use the Right and Left buttons to change the record
number by a factor of 10. Press ESC to return to the previous screen.
07/11/05 15:35
To the right, record #025 shows that a gas level of 7 ppm was measured
on 07/11/05 at 15:35.
The PPM Log can be cleared per Section 3.11.
LOG INT – Sets the interval at which measurements are logged to
memory from 1 to 9999 minutes. Factory default is 1 minute. The logged
measurements can be viewed using the PPM LOG function. Use the
Keypad to enter the desired value, and then press ENTER to save that
value and return to the previous screen.
FAULTS – Contains records of the last 30 fault events. The most recent
event is displayed when the Fault screen is first displayed. After 30
events have been recorded, the newest record overwrites the oldest. Each
record lists an event’s numeric fault code (refer to Section 3.10) plus the
date and time at which the event occurred. Use any of the Keypad
buttons to scroll through the other fault events. Press ESC to return to
the previous screen.
To the right, record #15 shows that a Purge Flow Fault (fault code
<1000>) occurred on 07/11/05 at 12:37.
0001 min
07/11/07 12:37
DIAG – Enters the diagnostic function. Refer to Section 3.13.
SILENCE – Sets the length of time the internal audible alarm is turned
OFF when the front panel SILENCE button is pressed. The factory default
is 30 seconds. If the cause of the gas-alarm has not been cleared at the end of
this time period, the internal audible alarm will reactivate. Use the Keypad
to enter the desired time period, and then press ENTER to save that value
and return to the previous screen.
12 Instruction 3015-4787
29.05cD 14.58psi
0030 sec
Page 17
N2O Portable Monitor Operation
14.07 * AMB14.05
-0.02dif <1000>
SET DATE & TIME
SELECT GAS TYPE
MEASURE 00500pk
2ndUNIT >PRINT
2ndUNIT PRINT
2ndUNIT PRINT
P-CHK – The Pressure Check function displays the current manifold
pressure and the stored ambient pressure in psia, along with the difference
between these two pressures and the current fault code. Refer to
Section 3.14.
GAS – Displays Nitrous Oxide (N
gas types are available for selection.
O) as the gas being monitored. No other
2
CLOCK – Sets the monitor’s date and time. Use the Keypad to enter
the correct date and time, and then press ENTER to save those values
and return to the previous screen. Note that time is displayed in a
24 hour format, while the date is displayed as mm/dd/yy.
2ndUNIT – One of following second measurements can be selected to
appear in the upper-right hand corner of the Data Display Screen:
• NONE – Blank
• Peak PPM – Peak gas reading
• Cont twa – Time Weighted Average calculated on a continuous basis
• 8hr TWA – Time Weighted Average calculated over an 8 hour period
PRINT – Refer to Section 3.15 Print/Plot Logged Gas Levels.
PLOT – Refer to Section 3.15 Print/Plot Logged Gas Levels.
PC-DUMP – A personal computer can be connected to the monitor’s DB9
RS-232 connector (refer to illustration in Section 3.15) for the purpose of
downloading logged ppm measurements. These measurements can later be
analyzed using any common spreadsheet program. Refer to Section 3.17 for
detailed instructions on how to transfer stored data to a personal computer.
N2O
07/11/05 15:30
100ppm N2O
PLOT PC-DUMP
>PLOT PC-DUMP
PLOT >PC-DUMP
Instruction 3015-4787 13
Page 18
Operation N2O Portable Monitor
FAULT CODE <1800>
FAULT CODE <1800>
#03 <0800> @
07/11/05 08:17
#04 <0000> @
3.10 Working with System Faults
3.10.1 Funct ional Overview
If a system malfunction occurs (see Fault Code list, page 15), the front panel FAULT light will flash and
the audible alarm, if activated (refer to AUDALRM function page 11), will start beeping.
3.10.2 Cl e aring / Silencing a Fault Alarm
The FAULT light and audible alarm will automatically turn OFF after the cause of the fault has been
eliminated.
Pressing the SILENCE button while a fault condition still exists causes the internal audible alarm to turn
OFF for a period of time as set by the SILENCE function (page 12). The front panel FAULT light will
continue to flash as a reminder that a fault condition still exists. At the end of the silence period if the
cause of the fault has not been corrected the audible-alarm circuit will reactivate.
3.10.3 Viewing the Faults Log
From the Data Display screen, press any of the Keypad buttons to display the first Function Menu
screen. Next, use the Keypad buttons to move the arrow (>) until it points to the FAULTS function, and
then press the ENTER button to display the FaultsLog screen.
The Faults Log screen shows the monitor’s current fault status. If the
fault is still present when the FAULTS function is selected, then the
current cause of the fault is displayed along with the date and time it
occurred. If the cause of the fault has been cleared, then the Faults Log
screen will show <0000> along with the date and time the fault was
07/11/05 09:00
12 SAMPLE FLOW
13 PURGE FLOW
The Fault Log can be cleared as described in the “Working with the Gas Alarm" section.
Gas-Alarm Light
If the detected gas level reaches the gas-alarm level as set by the ALRMLVL function, the front panel
ALARM (red) light will flash and the audible alarm, if activated (refer to AUDALRM function on page
11), will start beeping. The ALARM light and audible alarm will automatically turn OFF once the
detected gas level drops below the gas-alarm level.
cleared. Use the Keypad buttons to scroll through the fault log. In the
screens shown to the left, record #03 shows that a Sample Flow Fault (fault
code <0800>) occurred on 07/11/05 at 08:17, while record #04 shows that
the fault was cleared on 07/11/05 at 9:00.
The cause of the fault is identified by a numeric fault code. To convert the
fault code into a text description of the fault, first press the ENTER button
and then use the Keypad buttons to scroll through the display until the
text description of the fault appears. If the fault code is a combination of
two or more faults, then continue to use the Keypad buttons until all fault
text descriptions have been displayed. For example, the fault code <1800>
represents the combination of both a Sample Flow <0800> and a Purge
Flow <1000> fault as shown to the left.
Silencing a Gas Alarm
Pressing the SILENCE button while the alarm circuit is activated causes the audible alarm to turn OFF
for a period of time as set by the SILENCE function (page 12). The front panel ALARM light will continue
to flash as an indication that an alarm condition still exists. At the end of the silence period if the detected
gas level is still above the gas-alarm level the audible alarm will reactivate.
14 Instruction 3015-4787
Page 19
N2O Portable Monitor Operation
FAULT CODES ARE ADDITIVE. For example:
<0200> Gain Set Fault: The digipot autotune
3.10.4 Fault Codes
A fault code of <0003> indicates that both a Box
Temperature Fault <0001> and a Bench Temperature Fault <0002> have occurred.
<0001> Box Temperature Fault: Enclosure
temperature is outside normal range (or IR detector
has failed). Check that the monitor is not being
subjected to extreme temperatures. Use the
function to check the Box Temperature.
<0002> Bench Temperature Fault: Optical
bench is outside normal operating range (or IR
detector has failed). Check that the monitor is not
being subjected to extreme temperatures.
<0004> Manifold Pressure Fault: The manifold
pressure is outside its normal operating range (or
IR detector has failed). Enter the
DIAG function and
record ALL data. Call the factory with this
information for further instructions.
<0040> Fill Flow: The purge-air bag’s pressure
drop is outside expected limits. Use the
FILLBAG functions to refill the purge-air bag. If
and
the fault still occurs, check for a punctured bag or
disconnected tubing.
<0080> Over Range Fault: Monitor exposed to a
gas level that exceeded 65,000 ppm.
<0100> Zero Filter Fault: The air-purge bag is
contaminated with gas. Take monitor to a clean-air
area and use the
EMTYBAG and FILLBAG functions
several times to decontaminate the purge-air bag.
DIAG
EMTYBAG
sequence has failed. This fault will only occur on
first boot up or after a firmware upgrade. Call the
factory for further instructions.
<0400> A/D Fault: A fault has occurred in the
analog-to-digital circuitry. Contact the factory with
this information for further instructions.
<0800> Sample Flow Fault: Check for:
A restriction in the gas-sample inlet or exhaust; a
blocked internal filter; or a failed pump.
<1000> Purge Flow Fault: Check for:
A restriction in the gas-sample exhaust; a blocked
internal filter; or a failed pump. Once the purge air
stream has been restored, the monitor will return to
normal operation after it completes a purge cycle.
<2000> Bag Fill Time: The purge-air bag did not
fill within the expected time allotment, or too many
purge cycles occurred indicating a leak in the purgeair system. Check for a punctured bag or
disconnected tubing.
<4000> Zero Range Fault: The IR detector’s
output voltage is out of tolerance. Enter the
DIAG
function and record all data. Call the factory with
this information for further instructions.
<8000> Clipping Fault: The detector voltage may
be out of tolerance. Use the
DIAG function to check
the IR detector voltage. Call the factory with this
information for further instructions.
Instruction 3015-4787 15
Page 20
Operation N2O Portable Monitor
3.11 Working with the Gas Alarm
3.11.1 Gas-Alarm Light
If the detected gas level reaches the gas-alarm level as set by the ALRMLVL function, the front panel
ALARM (red) light will flash and the audible alarm, if activated (refer to AUDALRM function on page
11), will start beeping. The ALARM light and audible alarm will automatically turn OFF once the
detected gas level drops below the gas-alarm level.
3.11.2 Silencing a Gas Al arm
Pressing the SILENCE button while the alarm circuit is activated causes the audible alarm to turn OFF
for a period of time as set by the SILENCE function (page 12). The front panel ALARM light will continue
to flash as an indication that an alarm condition still exists. At the end of the silence period if the detected
gas level is still above the gas-alarm level the audible alarm will reactivate.
3.12 Clearing the PPM & Faults Data
Up to 200 gas measurements and 30 fault events are stored by the monitor.
To clear stored data, first display the data to be cleared by selecting the PPM LOG or FAULTS function
per Section 3.9.4. Next, press both the ENTER and Keypad Right buttons at the same time. A single,
long tone should be heard when the data has been successfully cleared.
3.13 Working with the DIAG Function
3.13.1 Overview
The DIAG function displays sensor data and status information useful to a service technician for
troubleshooting various fault conditions. Explanations of the data shown in these screens are given below.
3.13.2 Keypad Functions
From the Data Display screen, press any one of the Keypad buttons to display the first Function Menu
screen. Next, use the Keypad buttons to move the arrow (>) until it is next to the DIAG function, and
then press ENTER to display the first of two Diagnostic screens.
Press the KeypadUp button to toggle between the First and SecondDiagnostic screen.
16Instruction 3015-4787
Page 21
N2O Portable Monitor Operation
0.1ppm 0.01
PPM Level µMole/Liter
4.20885v <0000>
Bench Voltage Fault Code
0.00075n <0000>
Noise Fault Code
3.13.3 Fi rst Diagnostic Screen
29.05cD 14.58psi
35.40cB 14.59psi
In the First Diagnostic screen, the user can toggle between displaying Bench Voltage / Detector
Temperature, and Noise / Box Temperature by pressing the Keypad Right button.
Bench Voltage – This is the current peak-to-peak output of the IR detector. In the absence of gas this
value can range from 3.90000V to 4.50000V.
Noise –The Noise value is a 16 point running average of the noise portion of the IR detector’s output. This
reading is valuable mainly when gas is NOT present.
Detector Temperature – This is the current detector temperature in °C.
Box Temperature – This is the current internal enclosure temperature in °C.
Fault Code – Current fault code. A value of <0000> indicates that no faults are being detected.
Pressure Reading – This is the pressure as measured every purge cycle with the sample pump off and
the gas-sample inlet open. Its value is weather and altitude dependent and can range from 10.0 to
15.5 PSIA.
Detector Temperature °C ∗ Pressure Reading
Box Temperature °C ∗Pressure Reading
Purge Valve Asterisk (∗) – The purge valve can be opened and closed by pressing the Keypad Left
button. An asterisk appears on the display when the purge valve is open causing the monitor to draw air
from its purge-air port.
3.13.4 Sec ond Diagnostic Screen
0.00004au 4.210v
PPM Level – Parts Per Million Level is the current detected gas level, and is the volume concentration
referenced to standard temperature and pressure.
Average Absorption Unit – This is the optical absorbency. In the absence of gas the absorbency is
0.00000 au. When sampling gas, its value varies proportionally with the gas concentration.
µMoles/Liter – This is the absolute concentration in micro-moles per liter of gas.
Detector Voltage – This is a running average of the IR detector’s bench voltage.
Purge Valve Asterisk (∗) – The purge valve can be opened and closed by pressing the Keypad Left
button. An asterisk appears on the display when the purge valve is open causing the monitor to draw air
from its purge-air port.
Avg. Absorption Unit ∗ Detector Voltage
Instruction 3015-4787 17
Page 22
Operation N2O Portable Monitor
14.59 AMB14.75
Pressure Difference Fault Code
3.14 Working with the P-CHK Function
3.14.1 Overview
The P-CHK function (Pressure Check function) (page 13) is useful to a service technician for
troubleshooting a flow-fault problem. The monitor will trigger a flow fault if the pressure drop from
ambient is less than 0.2 psi during a purge cycle, and 0.5 psi during a measurement cycle.
3.14.2 Keypad Functions
From the Data Display screen, press both the Keypad Left and Right buttons at the same time to
display the first Function Menu screen. Next, use the Keypad buttons to move the arrow (>) until it
points to the P-CHK function, and then press ENTER to display the Pressure screen.
The Keypad Left button toggles the purge valve open and closed. Note that an asterisk (*) appears when
the purge valve is open causing the monitor to draw air from the purge-air bag.
The KeypadDown button toggles the pump ON and OFF.
Pressing the ENTER button stores the current manifold pressure shown on the left to the ambient
pressure shown on the right (must be done with the pump OFF).
3.14.3 Screen Displa y
-0.16dif <0000>
Current Manifold Pressure – Current manifold pressure in psia.
Stored Ambient Pressure – Stored ambient pressure in psia.
Pressure Difference – The difference between the current manifold pressure and the stored ambient
pressure.
Fault Code – Current fault code (page 15).
Purge Valve Asterisk (∗) – The purge valve can be opened and closed by pressing the Keypad Left
button. An asterisk appears on the display when the purge valve is open causing the monitor to draw air
from the purge-air bag.
Current Manifold Pressure ∗ Stored Ambient Pressure
18 Instruction 3015-4787
Page 23
N2O Portable Monitor Operation
2ndUNIT >PRINT
3.15 Print/Plot Logged Gas Levels
A printout or plot of the last 200 N2O ppm measurements can be made by connecting the optional
Bacharach printer and printer cable to the monitor as follows (refer to Section 5.1 for printer and cable
part numbers):
1. For a printout or plot to be made, the monitor must have been set up to record gas measurements
using the LOG INT function (page 12).
2. Interconnect the RS-232 connectors located on the printer and monitor.
3. If not already done, refer to the printer manual and set the printer’s communication
parameters to:
• Data bit = 8
• Parity = None
• Baud rate = 19200
• Handshaking = DTR
4.From the Data Display screen, press boththe Keypad Left and
Right buttons at the same time to display the first Function
Menu screen. Next, use the Keypad buttons to move the arrow (>)
until it points to either PRINT to produce a printout, or PLOT to
generate a plot.
5. Press ENTER to start the print/plot process.
PLOT PC-DUMP
Instruction 3015-4787 19
Page 24
Operation N2O Portable Monitor
3.16 Downloadin g Stored Data to a Person al Computer
Using the monitor’s PC DUMP feature (page 13), the last 200 N2O gas readings that were stored in
memory can be downloaded to a personal computer in ASCII text, comma-delimited format, which can
then be imported into most spreadsheet programs for analysis.
The following describes how to download data to a computer using Windows® HyperTerminal as the
communications program. If a different operating system and/or communications program is being used,
then consult the appropriate instruction manuals for those products.
1. Install serial data cable P/N 0104-4027 (straight through, 6 foot, DB9 male to DB9 female)
between the computer’s COM port and the analyzer’s RS-232 connector. (For computers having a
25-pin COM port, either use a 25-pin to 9-pin adapter, or use a serial cable with appropriate
connectors on each end.)
2. At the computer, start HyperTerminal by doing one of the following:
• If HyperTerminal has already been set up to communicate with the N
O Monitor, then click Start,
2
point to Programs, point to Accessories, point to Communications, click HyperTerminal, and
double-click the file name or icon that has been associated with the N
• If HyperTerminal has never been run in association with the N
O Monitor.
2
O Monitor, then a new
2
HyperTerminal connection needs to be made as follows:
a) Click Start; click Run. In the Run box, type “hypertrm.exe” and click OK. The New
Connection dialog box should appear.
b) Type in a New Connection Name such as “N2O”. Click OK to select the default icon (if
desired, select a different icon before clicking OK). The Connect To dialog box should
appear.
c) Click the Connect using drop-down menu and choose the COM port to which the analyzer
is connected. Then click OK to display the COM Properties dialog box for that COM port.
d) Set Port Settings to:
- Bits per second: 19200
- Data bits: 8
- Parity: None
- Stop bits: 1
- Flow control: None
Then click OK to display HyperTerminal’s main window.
e) Click File; click Save. This creates a file with an .ht extension in the folder C:\Program
Files\Accessories\Hyper Terminal, using the name that was entered in Step b.
3. After HyperTerminal is running: click Transfer, click Capture Text, and then click Start to accept
the default drive\directory\filename to which all received data will be stored as an ASCII text file.
Note: By default, the captured text file will be stored on the hard drive at C:\Program
Files\Accessories\HyperTerminal\CAPTURE.TXT. If desired, click Browse to select a different
drive, directory and filename. The next time data is captured, it will be stored under the same
location and filename.
Tip: Changing the filename extension to “CSV” (comma separated variable) will allow the file to be
directly opened in the spreadsheet program. For example, double clicking the filename
CAPTURE.CSV in Windows Explorer will automatically start Microsoft Excel and load the file.
20 Instruction 3015-4787
Page 25
N2O Portable Monitor Operation
2ndUNIT PRINT
4. From the Data Display screen, press both the Keypad Left and Right buttons at the same time
to display the first Function Menu screen. Next, use the Keypad buttons to move the arrow (>)
until it points to PC-DUMP, and then press the ENTER button to begin the download process.
PLOT >PC-DUMP
5. Observe that the N
is being received. After all data has been transmitted, the N
O Monitor’s screen goes blank and that HyperTerminal displays the data as it
2
O Monitor re-displays the Function
2
Menu screen.
6. To stop capturing data and save it, click Transfer, click Capture Text, click Stop.
7. HyperTerminal and the connection to the N
O Monitor can now be closed.
2
3.17 Importing Saved Data Into a Spreadsheet
A text file that was created as described in Section 3.17 can be imported into spreadsheet programs that are capable of
importing comma-delimited files.
The following describes how to generate a spreadsheet from a comma-delimited text file using Microsoft
Excel 2003. If you are using a different spreadsheet program, please refer to its instruction manual for
information on how to import comma-delimited text files.
1. Start Microsoft Excel.
2. Click Data, Import External Data, and Import Data to display the “Select Data Source” dialog box.
3. Locate file saved earlier. Select file, then click “Open” to display Excel’s “Text Import Wizard.”
4. Choose the “Delimited” original data type option and click Next.
5. Check the “Tab,” “Comma,” and “Space” delimiters and click Finish.
6. Choose “Existing worksheet” or “New worksheet” and click OK to create spreadsheet.
Note: A worksheet must be open in order to import data.
Instruction 3015-4787 21
Page 26
Maintenance N2O Portable Monitor
4 Maintenance
4.1 Disassembly
When servicing the parts inside the N2O Monitor, disassemble the monitor’s metal chassis as follows:
Items Required:
• Medium Phillips head screwdriver
Procedure:
1. Remove monitor and its battery pack from the soft carrying case.
2. Unplug battery pack from monitor.
3. Remove a total of 10 screws from the locations shown in the illustrations below.