Triplett GSM450 User manual

User Manual
GSM450
CO/CO2 Meter with RH% and Temperature
Introduction
Thank you for selecting the Triplett GSM450 Meter. The GSM450
measures CO2 (Carbon Dioxide) levels, CO (Carbon Monoxide) levels,
air temperature, and relative humidity. The GSM450 also displays dew
point and wet bulb temperatures, generated from calculations performed
on temperature and humidity measurements. The GSM450 is an ideal
instrument for indoor air quality (IAQ) analysi

Features
Adjustable carbon monoxide warning level
Designed with NDIR (non-dispersive infrared)
Long life electrochemical sensor
Audible and visual alarm
Backlit LCD for easy viewing in dimly lit areas
Low battery indicator
Auto power off
Mini USB connector
Manual and automatic recording
Safety Information
IMPORTANT CARBON MONOXIDE (CO) SAFETY NOTES
1. The GSM450 Carbon Monoxide Monitor is intended for general
purpose Air Quality monitoring only, and has not been certified for use
pursuant to any state or city safety Carbon Monoxide Alarm or
Monitoring requirements.
2. The GSM450 Carbon Monoxide Monitor has not been tested by an
independent lab to comply with the UL 2034 or IAS 6-96 standard.
3. It is the responsibility of the customer to obtain and apply current
local, state, and national regulations with regard to CO alarms,
monitoring and testing.
4. Electromagnetic (EMI) interference my cause erratic meter readings;
do not place meter near areas of high EMI when taking CO
measurements.
5. Recovery time is required after the meter has been exposed to high
levels of CO; the longer the exposure, the longer the recovery time.
Carbon monoxide is life threatening even at relatively
low concentrations; learn and recognize the effects of
CO poisoning (see Table below). Do not use this meter
as a personal safety-monitoring device

Effects of Carbon Monoxide (CO) poisoning
Warning: Ensure that the meter is powered, at room temperature,
and in an area free of Carbon Monoxide (CO) before starting
measurements. If not, the meter will read incorrectly when
subsequently measuring CO.
0-1 PPM
Normal background levels
9 PPM
Maximum allowable short term exposure
50 PPM
Maximum allowable continuous exposure level in any
8-hour
period, according to OSHA
200 PPM
Mild headache, fatigue, nausea and dizziness after 2-
3 hours
400 PPM
Frontal headache with 1-2 hours, life threatening
after 3 hours
800 PPM
Dizziness, nausea, convulsions within 45 minutes.
Unconsciousness
within 2 hours. DEATH WITHIN 2 TO 3 HOURS
1600 PPM
Headache, dizziness, nausea within 20 minutes,
DEATH WITHIN 1
HOUR
3200 PPM
Headache, dizziness, nausea within 5-10 minutes.
DEATH WITHIN
25-30 MINUTES
6400 PPM
Headache, dizziness, nausea within 1-2 minutes.
DEATH WITHIN
10-15 MINUTES
12800 PPM
DEATH WITHIN 1 TO 3 MINUTES

Regulatory exposure limits for Carbon Dioxide (CO2)
ASHRAE Standard 62-1989: 1000ppm: CO2 concentration in
occupied building should not exceed 1000ppm.
OSHA: 5000ppm: Time weighted average over five 8-hour
workday should not exceed 5000ppm.
Building bulletin 101 (BB101): 1500ppm. UK standards for schools
state that CO2 averaged over the whole day (i.e. 9:00am to 3:30
pm) should not exceed 1500ppm.
Germany, Japan, Australia, UK: 5000ppm, 8 hours weighted average
in occupational exposure limit is 5000ppm.
EPA Taiwan (Type 1): Indoor areas such as department stores,
theaters, restaurants, libraries have acceptable CO2 concentration of
1000ppm over an 8-hour average period.
EPA Taiwan (Type 2): Indoor areas with special requirements for
good air quality such as schools, hospitals, and day care centers
have suggested CO2 level of 600ppm
Description
METER
1. Temperature and Humidity sensor
2. Primary display
3. Secondary display
4. Power and Set button
5. Start and Escape button
6. Mode and Recall button
7. Min-Max-Avg and Enter button
8. Memory and Down button
9. CO and CO2 sensors (on rear of meter)
10. Hold and Up button
11. AC Adaptor and Micro USB ports
Battery compartment on rear of meter

LCD DISPLAY
CO2 Carbon dioxide
CO Carbon monoxide
TWA Time weighted average (8 hours)
STEL Short-term exposure limit (15 minutes weighted average)
HOLD Freezes current reading on display
MIN/MAX Minimum/Maximum readings
Low battery indicator
DP Dew point temperature
TA Air temperature
WBT Wet bulb temperature
%RH Relative humidity
C or F Celsius/Fahrenheit
CAL Calibration Mode
REC Manual/automatic data logging
RECALL View manually logged data

KEYPAD
Turns on and off the meter.
Enters setup mode while meter is off.
Sets as non-sleep mode with .
Exits setup/recall page.
Start automatic logging.
Press to switch displayed mode.
Long press to enter memory recall mode.
Freezes the current readings.
Selects unit or increases value in setup.
Cancels data hold function.
Press to manually record the reading.
Selects unit or decreases value in setup.
Activates MIN, MAX, TWA, STEL function. Saves and finishes
settings.
Battery Installation
1. Four (4) ‘AA’ batteries or an AC/DC adaptor powers the meter.
2. Install the batteries into the rear battery compartment observing
correct polarity.
3. When the adaptor is used, the batteries are disconnected
from the meter circuitry. The adaptor cannot be used to
charge rechargeable batteries.
4. When battery voltage is low, the battery symbol ( )
appears. Replace the batteries promptly.
Never dispose of used batteries or rechargeable batteries in household waste.
As consumers, users are legally required to take used batteries to appropriate collection sites, the retail store
where the batteries were purchased, or wherever batteries are sold.
Disposal: Do not dispose of this instrument in household waste. The user is obligated to take end-of-life devices
to a designated collection point for the disposal of electrical and electronic equipment.

Operation
Powering the Meter
Short press the /SET button to turn the meter ON or OFF. At
power up, the meter emits a short beep and performs a 30-second
warmup before entering normal operating mode. After the
countdown, the primary LCD will display the current readings. The
secondary display will alternate between the current date and time.
Taking Measurements
The meter begins measuring in the selected mode, when powered on,
and the sensor responds every 1 second. If the operating environment
changes (example: from high to low temperature), it requires 30
seconds for the CO2sensor to respond and up to 30 minutes for the
relative humidity sensor to respond.
Measuring Carbon Dioxide (CO2)
4. Short press the M/REL button to change the mode to CO2if
necessary.
5. To take a measurement, trace the GSM450 around the area of the
suspected leak.
6. The meter indicates the presence of carbon dioxide (CO2) in ppm
in the primary display. The secondary display indicates the current
date and time alternately.
NOTE: Do not hold the meter close to your mouth or any other source
of CO2.

Measuring Carbon Monoxide (CO)
1. Short press the M/REL button to change the mode to CO, if
necessary.
2. To take a measurement, trace the GSM450 around the area of the
suspected leak.
3. The meter indicates the presence of carbon monoxide (CO) in
ppm in the primary display. The secondary display indicates the
current date and time alternately.
4. The display will flash and an audible beeper sounds at 25 ppm
alerting the user to dangerous CO levels. The higher the
concentration of CO, the faster the beeper will sound. The
display will stop flashing once the measured CO is below the
alarm limit value.
Measuring Air Temperature and Calculating Dew point and
Wet bulb
1. Short press the M/REL button to change the mode to
air, dew point, or wet bulb temperature.
2. To take a measurement, trace the GSM450 in the testing area.
3. The primary display indicates the air temperature, dew point, or
wet bulb temperature depending on the selected mode. The
secondary display indicates the current date and time alternately.
4. Note that Dew Point and Wet Bulb Temperature displays are
calculations made from Air Temperature and Relative
Humidity measurements.
Measuring Relative Humidity %
1. Short press the M/REL button, if necessary, to change the mode to
Relative Humidity.
2. To take a measurement, place the GSM450 in the testing area.
3. The primary display indicates the relative humidity measurement
and the secondary display indicates the current date and time
alternately.

Advanced Functions
Data Hold
Short press the H/button to freeze the readings on the display. The
"HOLD” icon flashes in the top left of the display. Short press the H/button
again to unfreeze the readings on the display.
Note: the HOLD function is not operational in Min/Max/Avg mode.
Display Backlight
The meter is equipped with a backlight for easy viewing in dimly
lit areas. The backlight will activate for 10 seconds by pressing any
button.
MIN, MAX, STEL, TWA Recording
In normal operating mode, short press the MXMN/AV/button to
view the minimum, maximum, weighted average, and current
readings. With each short press of the MXMN/AV/button, the meter
displays the MIN, MAX, STEL, TWA, or current value along with elapsed
timer, in sequence. Short press the /ESC button to return to normal
operating mode.
In MIN and MAX modes, the meter shows the lowest (minimum) or
highest (maximum) reading in the primary display.
In STEL and TWA modes, the main display shows the weighted
average of readings for the past 15 minutes (STEL) or 8 hours (TWA).
TWA and STEL mode are only operational in CO2mode.
In CURRENT mode, the primary display shows the current readings. The
secondary display shows the elapsed timer. Press the /ESC button to
exit and return to normal operating mode.

NOTES:
1. If the meter is ON for < 15 minutes, the STEL value will be
the weighted average of readings taken since power on.
Similarly, for the TWA mode when the meter has been ON
for < 8 hours, the display only shows a weighted average of
the readings up to the moment.
2. The GSM450 requires at least 5 minutes calculating STEL and
TWA. The display shows “----” during the first 5 minutes from
power ON.
3. While in HOLD mode, the STEL and TWA values will continue to
update every 5 minutes.
4. Hold, Record, and Recall functions are not operational while in
Min/Max/Avg mode.
5. TWA and STEL will function only in CO2mode
6. The unit of measure can be changed while in Min/Max mode.
Manual Data Recording
The GSM450 has 99 memory locations for which to store readings one
at a time.
1. While in normal operating mode or hold mode, short press the
MEM/button to store a reading. The REC icon flashes on the
display for approximately 3 seconds. The primary display briefly
shows the memory location.
2. Each measurement parameter is saved, not just the currently
displayed parameter. (For example, when recording CO
readings, the CO2, %RH, and air temperature will also be
recorded).
3. Short press the H/button to freeze the readings on the
display before recording the data if the readings change too
quickly.
Note: The manual recording mode is not operational in Min/Max
mode.

Recalling Manually Stored Readings
The meter can recall up to 99 previously saved readings.
1. While in normal operating mode, long press the M/RCL
button until ‘Recall’ flashes on the display.
2. Short press the H/or MEM/buttons to scroll through
the memory locations. The selected memory location will
flash for approximately 3 seconds and then the stored
reading will display on the screen.
3. Short press the M/RCL button to change the displayed
measurement parameter.
4. The secondary display shows the time and date the data was
recorded into memory.
5. To exit memory recall mode, short press the /ESC button.
Automatic Datalogging
The GSM450 automatically records CO2, CO, Temperature, or RH
readings and can store up to 32,000 records. The sample rate can be set
from 1 second to 4 hours 59 minutes and 59 seconds. See ‘Setup Mode’
for information on setting the sample rate.
1. After the sample rate is selected, long press the /ESC button
to begin logging. The ‘rec’ icon flashes and the primary display
shows the real time value. The secondary display shows the
current time and date alternately.
2. Short press the M/RCL button to select a different measurement
mode to record.
3. To exit the datalogger mode, long press the /ESC button. The
‘rec’ icon stops flashing.
Notes:
Previous records are overwritten any time logging is started.
The M/RCL button is the only button that is operational while in
datalogging mode.

CO Alarm
The meter features an audible alarm (80db beep) that warns when
CO concentration exceeds the set limit. The beeper stops when the
readings fall below the limit. The meter beeps again if the value
exceeds the limit. See the section ‘Setup Mode’ for more
information.
Auto Power OFF
The meter turns off automatically after 20 minutes of inactivity. To
override the function, long press both the /SET and H/buttons
while powering ON the meter until “n” appears in the display.
NOTE: Auto power off is not operational while in calibration mode.
Setup Mode
While the meter is OFF, long press the /SET button to enter the setup
mode.
To exit the setup mode, short press the /ESC button at any time
during setup.
P10 Clearing the Manual Recording Memory
Clearing the memory will erase ALL the manually stored records.
1. Upon entering setup mode, P10 and “CLr” display on the LCD.
2. Short press the MXMN/AV/button to advance to P11 and
make a selection.
3. Short press the H/or MEM/button to select YES or
NO. ‘YES’ will erase all the manually stored records.
4. Short press the MXMN/AV/button to save the selection and
return to P10.
5. Short press the /ESC button to exit without saving.
6. Short press the H/button to advance to the next step.

P20 Setting the CO Alarm
1. When in alarm setup mode, P20 and “ALAr” are displayed.
Short press the H/button to advance to P20 if necessary.
2. Short press the MXMN/AV/button to advance to P21 and set
the CO alarm threshold. The current set value will blink on the
display.
3. Short press the H/button to increase or the MEM/button
to decrease the value. The alarm range is from 15 to 200ppm
and each press of the buttons will advance 5ppm.
4. Short press the MXMN/AV/button to save the selection and
return to P20.
5. Short press the /ESC button to exit without saving.
6. Short press the H/button to advance to the next step.
P30 Changing the Temperature Units
1. When in temperature setup mode, P30 and “unit” display
on the LCD. Short press the H/button to advance to P30
if necessary.
2. Short press the MXMN/AV/button to advance to P31 and
change the temperature units. The current temperature
unit displays on the LCD.
3. Short press the H/or MEM/button to toggle between °C
and °F.
4. Short press the MXMN/AV/button to save the setting and
return to P30.
5. Short press the /ESC button to exit without saving.
6. Short press the H/button to advance to the next step.
P40 Setting the Datalogging Sampling Rate
1. When in datalogging setup mode, P40 and “rAtE” display
on the LCD. Short press the H/button to advance to P40
if necessary.

2. Short press the MXMN/AV/button to advance to set the
sampling rate for datalogging. The hour digit will blink in the
secondary display.
3. Short press the H/button to increase the time or short
press the MEM/button to decrease the time.
4. Short press the MXMN/AV/button to save the setting
and advance to the minute setup.
5. Short press the H/button to increase the time or short
press the MEM/button to decrease the time.
6. Short press the button to save the setting and
advance to the second setup.
7. Short press the M button to save the settings and
return to P40.
8. Short press the button to exit without saving.
9. Short press the button to advance to the next step.
Note: The datalogging sampling range is from 1 second to 4 hours 59
minutes 59 seconds.
P50 Changing the Barometric Pressure Compensation
1. When in pressure setup mode, P50 and “PrES” display on the
LCD. Short press the H/button to advance to P50 if
necessary.
2. Short press the MXMN/AV/button to set the pressure
compensation value for the CO2measurement. The current
pressure compensation value in hPa will flash on the LCD.
3. Short press the H/or MEM/button to adjust the
barometric pressure value. The pressure compensation
range is from 70 to 199 hPA.
4. Short press the MXMN/AV/button to save the setting and
return to P50.
5. Short press the /ESC button to exit without saving.
6. Short press the H/button to advance to the next step.

P60 Setting the Real-Time Clock
1. When in Real-Time Clock mode, P60 and “rtC” display on the
LCD. Short press the H/button to advance to P60 if
necessary.
2. Short press the MXMN/AV/button to advance to P61 and
set the time as 12-hour or 24-hour format. The current time
format will flash on the LCD.
3. Short press the H/or MEM/button to change the format
between 12-hour and 24-hour.
4. Short press the MXMN/AV/button to save the setting and
advance.
5. The year will flash in the secondary display. Short press the
H/or MEM/button to change the value.
6. Short press the MXMN/AV/button to save the setting
and advance to the month setup.
7. Short press the H/or MEM/button to change the value.
8. Short press the MXMN/AV/button to save the setting and
advance to the next step.
9. Repeat the above steps to complete the setup for the
month/day/hour/minute/second settings.
10. Short press the MXMN/AV/button to save the selection and
return to P60.
11. Short press the /ESC button to exit setup mode.
Calibration
RH CALIBRATION
The meter is calibrated to a standard 33% and 75% salt solution
bottle. Calibration must be performed in a controlled
temperature environment of 25°C.
CAUTION: Do not calibrate the humidity without the default calibration
salts. The meter will lose its current calibration data and will become
inoperable.

33% Calibration
1. Plug the sensor probe into the 33% salt bottle.
2. Long press the /ESC, MEM/and /SET buttons
simultaneously to enter calibration mode.
3. In calibration mode, “CAL” and the current value (32.8% if at
25°C) will blink on the LCD.
4. The meter is now calibrating, and will finish in about 60
minutes, when the current value stops blinking. “CAL” will
continue to blink on the display.
5. To abort the calibration, power the meter OFF at any time.
75% calibration
1. After the 33% calibration, plug the sensor probe into a 75% salt
bottle.
2. Long press the MXMN/AV/button to enter 75% calibration.
3. “CAL” and current value (75.3% if at 25°C) will blink on the LCD.
4. The meter is now calibrating. The calibration is complete in
about 60 minutes. The values will stop flashing and the meter
powers OFF automatically when calibration is complete.
5. To abort the calibration, power OFF the meter at any time.
PC Interface
This meter has the capability to connect to and communicate with a
PC. To install and use the software, please refer to the instructions
provided on the supplied CD-ROM and/or the instructions provided
in the HELP Utility within the software program. Software can be
downloaded here:
Download Triplett Product Software —Triplett —Triplett
Test Equipment & Tools

Troubleshooting
Error
Problem
Solution
Ensure that batteries are
properly
installed with correct
polarity
Display
No display when pressing
power button
Press and hold power
button to retry
Replace batteries
Open the battery
compartment and
using a small metal tip,
press the
reset button
Display
Readings frozen on display
Check to see if data hold
function is
activated. Press hold to
deactivate.
Display
Slow Response
Check for air flow
blockage to
sensors
E01/E33
CO2sensor is not working
Replace the battery
E02
Measurement is below the
range of the meter
Check readings in a
different area
E03
Measurement is above the
range of the meter
Check readings in a
different area
E04
Data error
Contact Extech for
service
E11
Humidity calibration Error
Retry humidity
calibration
E16
CO calibration error
Contact Extech for
service

E31
A/D or temperature sensor
failure
Contact Extech for
service
E32
Memory failure
Contact Extech for
service
E33
A/D or humidity sensor failure
Contact Extech for
service
E33
Measurement circuit failure
Contact Extech for
service
Maintenance
CLEANING AND STORAGE
1. Clean the meter with a damp cloth and mild detergent when
necessary. Do not use solvents or abrasives.
2. Store the meter in an area with moderate temperature and
humidity (refer to the operating and storage temperature
ranges in the specifications section).

Specifications
Function
Range
Resolution
Accuracy
0 to 5000ppm
1 ppm
±(5%rdg + 30ppm)
CO2
5001 to
9999ppm
1 ppm
Not specified
Pressure dependence: +1.6% of reading per kPa
deviation from
normal pressure (100kPa)
<100 ppm
1 ppm
±(10ppm)
CO
101 to 500 ppm
1 ppm
±(10%rdg)
501 to 1000 ppm
1 ppm
±(20%rdg)
Temperature
-20 to 60°C
0.1°
±0.6°C
-5 to 140°F
0.1°
±0.9°F
Humidity
0.1 to 99.9%
0.1%RH
±3%(10 to 90%) @25°C
±5%(all other
ranges)@25°C
Wet Bulb
-5 to 59.9°C
0.1°
23 to 140°F
Calculated from RH and
Dew Point
-20 to 59.9°C
0.1°
Temperature
-4 to 140°F
Display
LCD with backlight
Display size
26 x 44 mm (1.0 x
1.7”)
Warm-up
period
30
seconds
Response
Time
CO2: <30 seconds (90% step change)
CO: <60 seconds (90% step change)
Tair: <2 minutes (90% step change)
RH: <10 minutes (90% step change)
Sensor Type
CO2: NDIR (non-dispersive infrared) technology
Humidity: Capacitance sensor

Temperature (air): Thermistor
Operating Conditions
-20 to 50oC (-4 to 122oF) CO2sensor
0 to 50oC (32 to 122oF) CO sensor
-20 to 50oC all other parameters
Storage Conditions
-20 to 60oC (-4 to 140oF); 10 to 90% RH non-
condensing
Power Supply
4 x 1.5V ‘AA’ batteries or AC adaptor (9V)
Battery Life
approx. 24 hours (alkaline batteries)
Dimensions / Weight
205 x 70 x 56mm (8.1 x 2.8 x 2.2“) / 200g (7.1
oz.)
Warranty
Triplett / Jewell Instruments extends the following warranty to the original purchaser of
these goods for use. Triplett warrants to the original purchaser for use that the products
sold by it will be free from defects in workmanship and material for a period of (1) one
year from the date of purchase. This warranty does not apply to any of our products
which have been repaired or altered by unauthorized persons in any way or purchased
from unauthorized distributors so as, in our sole judgment, to injure their stability or
reliability, or which have been subject to misuse, abuse, misapplication, negligence,
accident or which have had the serial numbers altered, defaced, or removed.
Accessories, including batteries are not covered by this warranty
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