HTA 77596, 77597 Operation Manual

OPERATION MANUAL

PORTABLE IAQ METER

Model:

77597, 4 in 1
77596, 3 in 1

INTRODUCTION

1

Thank you for purchasing this portable
IAQ meter. The meter measures CO

2

level,CO level, air temp., dew point, wet
bulb temp. and humidity(DP, WB, RH are
for models 77597 only) and is an ideal
instrument for indoor air quality (IAQ)
diagnosis.

Poor indoor air quality is considered
unhealthy because it causes tiredness,
loss of ability to concentrate, and even
illness(ex. Sick Building Syndrome). IAQ
monitoring and survey, especially on CO

2

level and air ventilation become widely
applied in public areas such as offices,
classrooms, factories, hospitals and
hotels. It is also suggested in regulations
of industrial hygiene in some countries.
(Appendix)

The portable CO meter uses NDIR (non-

2

dispersive infrared) technology to ensure
the reliability and long term stability. It’s
useful in verifying HVAC system perform­ance and air ventilation control.

CO is a colorless, odorless, and tasteless
gas which is slightly lighter than air. It is
highly toxic to humans and animals.

Maximum indoor air quality level per
ASHRAE Residential standards 62-1989
for living area is under 9ppm. Besides, it is
also necessary to remove employees from
enclosed space if the CO concentration
exceeds100ppm per OSHA exposure limit.
Please refer to Appendix for the details.

Features:

Big LCD display with blue backlight
to use in dark area
One touch to display CO2 /Dew point
temperature/Wet bulb temperature/
Air temperature/Humidity/CO in turns.
Designed with NDIR (non-dispersive
infrared) Waveguide technology CO2
sensor
Programmable warning CO level
Long time drift compensation on CO2
sensor
Audible alarm (~80db)threshold setting
Max, Min, TWA, STEL functions included
Mini USB to PC download function for
analysis
99 points manually recording
32000/24000 points auto recording
Review 99 points manual record
Hold function freezes current readings
Housing design surrounds with rails to
help Air ventilation for quick & accurate
response
Easy to manually calibrate CO2 at
fresh air around 380-420ppm

MATERIAL SUPPLIED

Meter
4pcs AA batteries
Mini USB cable and software CD
Operation manual
Hard carrying case

This package contains:

Optional accessory:

33% calibration salt (VZ0033AZ1)
75% calibration salt (VZ0075AZ1)
Adaptor (9V/100~240Vac)

2

POWER SUPPLY

The meter is powered by either 4 AA
batteries or a DC adaptor(9V/1A output).

Install the batteries into the battery
compartment on the rear and make sure
they are in correct polarity and good
contact.

will

appear on the LCD .

atter

When an adaptor is used, it will
cut off the power supply from batteries.
The adaptor can’t be used as a battery
charger.

When battery voltage gets low,

(Fig.1)

The CO sensor can’t work normally

2

under low voltage, please replace with
fresh b ies or connect with an
adaptor.

3

B

CO2

PM

B

Fig.1

HOLDHOLD

CO2

%rhrh

TA

DP

WBT

OO

FF

OO

CC

REC

Recall

AM

PM

CO

CAL

B

MINMIN
MAXMAX
AVGAVG

4

LCD DISPLAY

Upper LCD

MIN/MAX Minimum/Maximun readings
STEL Short-term exposure limit (15
minutes weighted average)
TWA Time weighted average(8 hours)
Low battery indicator
DP Dew point
TA Air temperature
WBT Wet bulb
%rh Unit of relative humidity (77597)

o

C/ F Celsius/Fahrenheit of temp.
CAL In calibration status
REC In manual/automatic logging
RECALL In manual records recall mode

CO2/CO/Temp....reading

Lower LCD Real time display

CO2 Carbon dioxide reading
CO Carbon monoxide reading

HOLD Readings are freezed unchanged

temperature(77597)

temperature(77597)

o

Symbols

Turns on and off the meter.
Enters setup mode while meter is off.
Sets as non-sleep mode with .

SET

START
ESC

Exits setup/recall page.
Start automatic logging.

KEYPAD

ON/OFF

MODE
RECALL

HOLD

Press to switch displayed mode.
Long press to enter memory recall mode.

TWATWA
STELSTEL

B

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.

OPERATION

Press to turn the meter on and off.
At power up, it emits a short beep and
performs 30 seconds countdown(Fig.2)
for meter warm up, then enters normal
mode with current CO and real time

2

displayed (Fig.3). The real time display
date and time in turns.

Suggest to wait for 30 seconds warm up
time. For quick start, you may press
for 2 seconds to end the warm up
and entering normal display.

POWER ON/OFF

SET

ON/OFF

Fig.2

Fig.3

CO2

AM

TAKING MEASUREMENT

The meter starts measurement when
power on and update readings every
second. In the condition of operating
environment change (ex. from high to
low temp.), it takes 30 sec to respond
for CO sensor and 30 minutes for RH.

2

NOTE: Do not hold the meter close to
faces in case exhalation affects CO

2

levels.

N
X

M /AVG

5

HOLD

MEM

N
X

M /AVG

6

Press to switch to temperatures
display.(Fig.6). In 77597 model, dew
point temp. and wet bulb temp. are also
available.(Fig.7). The lower display
shows the real time clock.

AIR(all models),DP,WBT(77597)

Press to switch the mode to CO2.
User can get the CO2 reading in ppm
unit on main display.(Fig.4). The lower
display shows the real time clock.

CO2 (Carbon Dioxide)

MODE
RECALL

CO2

AM

Fig.4

Press to switch the mode to CO.
User can get the CO reading in ppm
unit on main display.(Fig.5). The lower
display shows the real time clock.

CO (Carbon Monoxide)

MODE
RECALL

CO

AM

Fig.5

MODE
RECALL

TA

OO

CC

PM

WBT

OO

CC

Fig.6

Fig.7

Press to switch to humidity display.
(Fig.8).The lower display shows the real
time clock.

Humidity (77597)

MODE
RECALL

%rhrh

Fig.8

DATA HOLD
In normal display mode, press to
freeze the readings, "HOLD” icon is
flashed on the left top of LCD(Fig.9). All

current readings are kept unchanged.
Press again to cancel the hold
function.

Fig.9

BACKLIGHT

The backlight will be activated for 10

seconds by pressing any key.

MIN,MAX,STEL,TWA, CURRENT REVIEW

This meter allows you to check the

minimun, maximun, STEL,TWA and

current value from the moment you press

the key. Under normal mode, press
to see the minimum, maximum,
STEL, TWA and current value in turns.
Each press of ,it displays MIN, MAX,
STEL,TWA, current value in sequence.
(Fig.10~12). To return to normal mode,
press key to escape(Fig.13)

If the meter is turned on for shorter than
15 mins, the STEL value will be the
weighted average of readings take since
power on. Same for TWA values appear
before 8 hours.

It takes at least 5 mins to calculate STEL
and TWA. The display shows “----” during
the first 5 mins from power on.

HOLD

HOLD

HOLDHOLD

%rhrh

AM

NOTE:
THE HOLD FUNCTION IS DISABLE IN MIN/MAX/
AVG MODE.

N
X

M /AVG

N
X

M /AVG

N
X

M /AVG

START
ESC

7

In this max/min/STEL/TWA/current
modes, it shows the corresponding
readings on main display and the
accumulated time of how long you are
in this mode.(Fig10~12).

NOTE:
“HOLD” & “MANUALLY
RECORD” & “RECALL”
FUNCTION ARE DISABLE
IN MIN/MAX/AVG MODE.

MODE
RECALL

CO

MAXMAX

Fig.14

START
ESC

While in “HOLD” mode, STEL and TWA
will remain updating every 5 mins.

CO2

MINMIN

CO2

CO2

CO2

AM

Fig.10

Fig.11

Fig.12

Fig.13

8

TWATWA

In this mode, press to switch the
displayed parameters. Fig 14.

The dispalyed sequence in this mode is
min max STEL TWA current min

max.....Press key can immediately

leave this mode and return to normal.
Distinguishing the normal display and

current review by checking the time
display format. In normal display, the
date & time displayed in turns. In current
review, the time display is the accumu-
lated time of how long you are in
max/min mode.

NOTE:
TWA &STEL ARE FOR CO2
ONLY.
MIN/MAX ARE FOR ALL
PARAMETERS.

parameter you choose to see on main
display.

TA

REC

AM

Fig.15

If the reading changes
quickly, you can press
to freeze the
reading before
manually recording
the data.

HOLD

99 MEMORIES RECALL

The meter features 99 point memories

review function.

In normal or hold mode, press key

for more than 2 seconds until the

icon flashes.

Press or to scroll the memories.

The memory serial number displays on

main LCD fist and reading comes after.

(Fig.16&17)

MODE
RECALL

Recall

Recall

CO2

Recall

PM

HOLD

MEM

Fig.16 Fig.17

MANUALLY RECORDING

The meter features 99 point memories.
In normal or hold mode, Press key

to record, icon and main display
flash for about 3 seconds. The main
display shows the memory serial number
, at most 99 points.(Fig. 15)

Each memory contains all parameters

(CO2, CO, TA.....%rh), not only the

MEM

REC

The manually recording function is
disabled in min/max mode.

9

ALARM

The meter features audible alarm to

give warnings when CO concentration

exceeds the limit. (See P20 in setup

for setting alarm threshold). It emits

beeps(Abt.80dB)when CO level goes　

over the set value　and stops only when

the readings fall below the set value. It

beeps again when value goes over the

limit.

To escape the memory recall mode,
press key to leave and return to
normal display.

START
ESC

DATA LOGGING

The meter can automatically record
readings of CO2/CO/TEMP./RH for long
time environment monitoring. The
memory capacity is 32000 (#77597) or
24000 (#77596) points. Users can set
up sampling rate from 1 second to 4hours
59 minutes and 59 seconds (See
SETUP P40).

After sampling rate is selected, press
for 2 seconds under normal
mode to start logging. The icon
flashes to indicate the logging status
and LCD main display shows the real
time CO2 value. Lower displays are the
real time clock.(Fig.19)

START
ESC

REC

10

MODE
RECALL

CO

Recall

PM

Fig.18

The time displayed in memory recall
mode is the recording time of this
memory.

Press key to switch the display
parameter.(Fig.18)

CO2

REC

Fig.19

To terminate data logging, press
for 2 seconds, icon stops flashing

While press to start the logging
again, the previous logging records are
overwrite.

Press key to switch to the mode you
want to see. Except the mode switch
function, min/max, manual record, hold
and recall functions are all disabled
during logging.

START
ESC

REC

START
ESC

MODE
RECALL

The meter turns off automatically after
20 minutes of inactivity. To override the
function, hold down and for 2
seconds to turn on the meter until “n”
appears.(Fig.20)

NOTE:
AUTO SLEEP FUNCTION WILL BE
DISABLED DURING CALIBRATION
MODE.

AUTO POWER OFF

SET

ON/OFF

HOLD

When the meter is off, hold down
for more than 1 sec to enter setup mode.
To exit setup, press in P10 ~ P60
and it returns to normal mode. (Fig.21)

SETUP

Fig.20 Fig.21

SET

ON/OFF

START
ESC

11

P20: CO ALARM

12

P10: 99 MEMORIES CLEAR

When entering setup mode, P10 and
“CLr” (Fig.21) are displayed on the LCD.
Press to go into P11 and decide to
clear or keep all the manual records.
The current set will be blinking on LCD
(Fig.22).

Press or to choose NO or YES
and press to confirm.

N
X

M /AVG

HOLD

MEM

N
X

M /AVG

Fig.22

Press to escape and return to P10.

START
ESC

When entering setup mode, P20 and
“ALAr” (Fig.23) are displayed on LCD.
Press to go into P21 for setting
CO alarm threshold. The current set
value will be blinking on LCD(Fig.24).
Press to increase the value or
to decrease. The selectable alarm
limits are 15~200ppm,each press tunes
5ppm. When the preferred alarm value
is set, press to save the setting or
without saving and return to P20.

N
X

M /AVG

HOLD

MEM

N
X

M /AVG

START
ESC

CO

CO

Fig.23 Fig.24

P40:LOGGING SAMPLING RATE

P30 TEMPERATURE UNIT

When entering setup mode, P30 and
“unit” (Fig.25) are displayed on the LCD.
Press to go into P31 and decide the
temperature unit.

The current set will display on LCD
(Fig.26).

o o

Press or to choose C or F
and press to confirm.

N
X

M /AVG

HOLD

MEM

N
X

M /AVG

Fig.25

Press to escape and return to P30.

START
ESC

Fig.27 Fig.28

Fig.26

TA

OO

CC

TA

Go into P40 for setting sampling rate
of data logging(Fig.27). The range is
from 1 second to 4 hours 59 minutes
and 59 seconds.

Press and it goes into setting
with blinking Hour digits on the lower
display. To change the digit, press
to increase and to decrease. Press
to confirm and enter Minute setting
. Press again to confirm and enter
Second setting (Fig.28). Press
to confirm the rate setting or
without saving and return to P40.

N
X

M /AVG

HOLD

N
X

M /AVG

N
X

M /AVG

START
ESC

13

MEM

N
X

M /AVG

P60:REAL TIME CLOCK

P50 PRESSURE COMPENSATION

When entering setup mode, P50 and
“PrES” (Fig.29) are displayed on the LCD.
Press to set pressure compensation
value for CO2 measurement.

The current set will flash on LCD
(Fig.30).The barometric pressure unit
is kpa.

Press or to adjust the pressure
value and press to confirm.

N
X

M /AVG

HOLD

MEM

N
X

M /AVG

Fig.29

Press to escape and return to P50.

START
ESC

Fig.31

Fig.32

Fig.30

Go into P60 for setting the real time
clock of this meter.

Press and it goes into P61to set
the time format as 12hour or 24 hour.
The current set will flash on LCD. Press
or to change the format and
press to confirm and entering real
time clock setting.(Fig.31)

The blinking Year digits on the lower
display. To change the digit, press
or to adjust. Press to confirm
and enter Month setting. Repeat above
steps to complete the month/date/hour/
minute/second setting.(Fig.32)

N
X

M /AVG

HOLD

MEM

N
X

M /AVG

N
X

M /AVG

CO2

CO2

HOLD

MEM

PM

14

15

CO CALIBRATION

2

CAUTION:

Do not calibrate the meter in the air
with unknown CO concentration.

2

Otherwise, it will be calibrated as
400ppm by default and leads to
inaccurate measurements.

NOTE:

Ensure the batteries are with full voltage
during the calibration to prevent from
interruption or failed calibration.

The manual calibration is suggested to
to be done in fresh outdoor air that is
well ventilated and in sunny weather.

Place the meter in the calibration site.
First press + , then also
simultaneously for 3 seconds to turn on
the meter and enter calibration mode
(Fig.33). Three calibration menu is
available: Humidity/CO/CO2.

Press key to select the CO2
calibration. 400ppm and “ “ icon
are blinking on the LCD. Press
to start calibration. (Fig.34)

Wait about 10 minutes until the blinking
stops and the calibration is completed
automatically. To abort the calibration,
turn off the meter at any time.

The meter is calibrated at standard
400ppm CO concentration in factory.

2

It’s suggested to do manual calibration
regularly to maintain good accuracy.

Note:

When the accuracy becomes a concern
after a long time usage, return to dealers
for standard calibration.

START
ESC

MEM

SET

ON/OFF

N
X

M /AVG

CAL

N
X

M /AVG

%rh%rh

CAL

CO2

CAL

Fig.33

Fig.34

33% calibration

Plug the sensor probe into 33% salt
bottle. First p

Hold down to enter 33%
calibration. ¡§CAL¡¨ and calibrating value
(32.8% if at are blinking on the
LCD.

Meter is now calibrating, and will finish
in about 60 minutes when ¡§CAL¡¨ and
humidity stop blinking.

ress + , also
simultaneously for 3 seconds to turn on
the meter and enter calibration mode
(Fig.33.).

o

25 C)

To abort the cali-

bration, turn off the meter at any time.

The meter defaults to be calibrated the
humidity with 33% and 75% salt solution.
The ambient condition is recommended

o

to be at 25 C and stable humidity(better
to be close to the calibrating value). To
abort calibration, just turn off the meter.

(77597)

RH CALIBRATION

CAUTION:

Do not calibrate the humidity without
the default calibration salt. Otherwise,
it will cause permanent damage.
Contact the dealer for calibration salt
or services.

START
ESC

MEM

SET

ON/OFF

N
X

M /AVG

75% calibration

Plug sensor probe into 75% salt bottle
and entering calibration mode. In
calibration mode, press to select
75% calibration(Fig.35), press to
start.

HOLD

N
X

M /AVG

16

CAL

17

“CAL” and calibrating value (75.3% if at

o

25 C) are blinking on the LCD.
Meter is now calibrating, and will finish

in about 60 minutes when “CAL” and
humidity stop blinking. To abort the cali­bration, turn off the meter at any time.

%rh%rh

Fig.35

CO CALIBRATION

CAUTION:

Do not calibrate the meter in the air
with unknown CO concentration.
Otherwise, it will be calibrated as
0 or 400ppm by default and leads to
inaccurate measurements.

When the accuracy becomes a concern
after a long time usage, return to dealers
for standard calibration. It is necessary
to have standard CO gas for calibration.

Place the meter in the calibration site.
First press + , then also
simultaneously for 3 seconds to turn on
the meter and enter calibration mode
(Fig.33).

Press or to select the CO
0ppm or 400ppm calibration. ppm and
“ “ icon are blinking on the LCD.
Press to start calibration.
(Fig.36&37)

Wait about 10 minutes until the blinking
stops and the calibration is completed
automatically. To abort the calibration,
turn off the meter at any time.

START
ESC

MEM

SET

ON/OFF

HOLD

MEM

N
X

M /AVG

CAL

? Error messages

E01/E33: CO sensor is out of order. Try

2

new battery first.
E02: The value is under range.
E03: The value is over range.
E04: The original data error results in
this error (DP, WB)
E11: Retry humidity calibration.
E16: Retry CO calibration.
E31: Temperature sensor or AD damaged.
E32: Memory IC damaged.
E33: Humidity sensor or circuit damaged.

? Can’t power on

-Press for more than 0.3 seconds
and try again. Check whether batteries
are in good contact and correct polarity,
or the adaptor is well plugged.

-You may also take off the batteries for
10 mins and then put back again.

-Open the battery cover
and use a small metal
tip to touch and reset
the meter.

TROUBLESHOOTING

? Fixed readings

Check whether data hold function was
activated. (HOLD icon at the left top)

? Slow response

Check whether the air flow channels on
the rear were blocked.

CO

CAL

SET

ON/OFF

NOTE: It is allowed to adjust the CO
calibration point from 385~415ppm
(400+15ppm)

CO

CAL

Fig.36

Fig.37

18

Reset point

19

PC CONNECTION

Connect the logger to PC, users can do
logging setting and data transmission
with the included software.

Plug the USB cable into the socket at
the right side of the meter and the other
port to PC. Then install the software in
your PC with the following procedure.

1.Insert the CD Rom and run installation.
Select a preferred directory and click
“Next” step by step and finish it.

2. After the software installation is
completed, it will run USB driver
installation next.

20

Software Operation

Start the software and it will detect
logger connection automatically and
indicate the COM Port information at
the bottom of the main screen as well
as the COMPort setting column.

Logger Settings

To set up logging plan, click “Setting”
icon and select “Logger”. The setting
page is opened.

Users can set up the logger identifier
number. Click OK for setting and Exit
the screen to confirm the settings.

AutoConnect

Data Transmission

To transmit auto recorded data from the
meter, click “Download” icon on the left
top side of the main screen. All auto­recorded data in the logger will be
transmitted. The raw data with time
stamp will display at the lower part of
the screen and the graph in the middle.

In the Graph display, the Y-axis indicates
Temp, RH,DP, WBT, CO2&CO level in
different line colors. And the X-axis can
be switched to show Time or Recorded
No. Stamp.

Data Review Function

The following functions help to view
the GRAPH data in more detailed way.

Under View function, there are 4 tools
to enlarge the Graph data for detailed
data review.

Zoom in: Hold down “Ctrl” key on the PC
keyboard and click any target point on the
graph. It enlarges the point in each click.

21

22

Zoom Xaxis: Hold down “Ctrl” key and
drag click the left button of the mouse to
select an area on the Graph and the
X-axis of the selected area will be
enlarged.

Zoom Yaxis: Hold down “Ctrl” key and
drag click the left button of the mouse to
select an area on the Graph and the
Y-axis of the selected area will be
enlarged.

Three icons on the right top side of the
main screen:

Redraw: After any review and zooming
on the Graph, click “Redraw” to reset it
to original format.

Clear: Click “Clear” to delete all data
and Graph on the window. A warning
box shows up for confirmation. Press
“Yes” and all data will be cleared.

Cursor: Switch Cursor ON and it shows

the raw data with the cursor. In any click
on the graph, the digital data displayed.
Switch OFF to disable the function.

Zoom window: Hold down “Ctrl” key and
drag click the left button of the mouse to
select an area on the Graph and the
selected area will be enlarged .

Data Processing
The downloaded data can be Saved or

Printed via “File” processing functions.
Load: To retrieve saved files, just click

“Load” and select a desired file and it
will be loaded in the main screen with
the file details at the left top side.

SPECIFICATION

23

Measuring range

o o

-20~60 C (-5~140 F)

CO2

Temperature

Accuracy
CO2

Temperature

o o

+0.6 C/+0.9 F

30 seconds

CO2 Warm-up time
Response time
CO2

Tair

LCD / Meter size (mm)
Operating condition

(avoid condensation)
Storage condition
Power supply

Weight
Standard package

<30 seconds(90% step change)

<2 mins (90% step change)

26(H)x44(L), 205(L)x70(W)x56(H)

-20 to 50 °C (CO2 sensor),0 to 50 °C (CO sensor)

-20 to 60 °C (for the rest parameters)

o

-20~ 60 C,10~90%RH(avoid condensation)
AA x 4pcs or 9V adaptor

200g

Meter, manual ,AA bat.,USB cable &CD, carry case

77597

77596

0~9999 ppm, 0~9999 ppm,

(5001~9999 ppm out of scale range)

+30ppm+5% of reading( 0~5000ppm)

Other ranges are not specified

Battery life

> 24 hours (Alkaline battery)

Resolution

o o

1ppm , 0.1 C/ F, 0.1%RH

Relative Humidity
DP(Dew point temp.)
WB(Wet bulb temp.)

0.1%~99.9%RH

o

-20.0~59.9 C

o

-5.0~59.9 C

Relative Humidity

o o

+3%RH (at 25 C, 10~90%RH) ; +5%RH ( at 25 C , other range )

RH

<10 minutes ( 90% step change)

(5001~9999 ppm out of scale range)

CO

0~1000 ppm, 0~1000 ppm,

N/A
N/A
N/A

CO

+/-10 ppm for less than 100 ppm
+/-10% or reading for 101~500 ppm
+/-20% of reading for 501ppm and above

CO

<60 seconds(90% step change)

24

CO2 LEVELS AND GUIDELINES

EPA Taiwan: 600ppm and 1000ppm
Type 1 indoor areas such as department

stores, theaters, restaurants, libraries,
the acceptable CO2 concentration of 8
hours avarge is 1000ppm.
Type 2 indoor areas with special requirements
of good air quality such as schools,
hospitals, day care centers, the
suggested CO2 level is 600ppm.

NIOSH recommendations
250-350 ppm: normal outdoor ambient

concentrations

600 ppm: minimal air quality complaints
600-1000 ppm: less clearly interpreted
1000 ppm: indicates inadequate ventilation;

complaints such as headaches,
fatigue, and eye/throat irritation
will be more widespread. 1000
ppm should be used as an upper
limit for indoor levels.

Non-Enforced Reference levels

Regulatory exposure limit

ASHRAE Standard 62-1989: 1000ppm

CO2 concentration in occupied building should

not exceed 1000ppm.
Building bulletin 101 (BB101):

UK standards for schools say that CO2 at

1500ppm

averaged over the whole day(i.e. 9am to 3.30
pm) should not exceed 1500ppm.

OSHA: 5000ppm
Time weighted average over five 8-hour work
days should not exceed 5000ppm.

Germany, Japan, Australia, UK...: 5000ppm
8 hours weighted average in occupational
exposure limit is 5000ppm.

ppm

Symptoms and applicable standard

9

Maximum indoor air quality level:
Maximum allowable concentration per
ASHRAE Residential standards
62-1989 for living area.

25

Maximum limit 8 hrs of continuous
exposure per California OSHA
workplace standards.

35

Maximum 8 hrs average exposure
level per US OSHA workplace standards.

50

Maximum concentration for continuous
exposure in any 8 hrs average level per
OSHA standards.

100

Remove employees from enclosed
space if the CO concentration exceeds
100ppm per OSHA exposure limit.

400

Frontal headache, life threatening
after 3hrs. Maximum concentration
in flue gas per the US EPA and AGA
standards.

1600

Nausea w/i 20 min.,death w/i 2-3 hrs

200

Mild headache, fatigue, nausea and
dizziness w/i 2-3 hrs.

Dizziness, nausea, convulsions, death
w/i 2-3 hrs.

0-1

Normal background levels

800

CO LEVELS AND GUIDELINES

25

26

WARRANTY

The meter is warranted to be free from
defects in material and workmanship
for a period of one year from the date
of purchase. This warranty covers
normal operation and does not cover
misuse, abuse, alteration, neglect,
improper maintenance, or damage
resulting from leaking batteries. Proof
of purchase is required for warranty
repairs. Warranty is void if the meter

has been opened.

RETURN AUTHORIZATION

OTHER RELATED PRODUCTS

Authorization must be obtained from
the supplier before returning items for
any reason. When requiring a RA
(Return Authorization), please include
data regarding the defective reason,
the meters are to be returned along
with good packing to prevent any
damage in delivery and insured against

possible damage or loss.

Other related CO products:

2

a.Model 7721 Wall mount Temp./CO

2

meter, general purpose.
b.Model 77231 Wall mount Temp./CO

2

meter, high performance.
c.Model 7722 Wall mount Temperature/RH/

Co meter, general purpose.

2

d.Model 77232 Wall mount Temperature/RH/
Co meter, high performance.

2

Accuracy, the Zenith of
Measuring / Testing Instruments !

More products available !

Hygrometer/Psychrometer
Thermometer
Anemometer
Sound Level Meter
Air Flow meter
Infrared Thermometer
K type Thermometer
K.J.T. type Thermometer
K.J.T.R.S.E. type Thermometer
pH Meter
Conductivity Meter
T.D.S. Meter
D.O. Meter
Saccharimeter
Manometer
Tacho Meter
Lux / Light Meter
Moisture Meter
Data logger
Temp./RH transmitter

Wireless Transmitter ..........

2012/03 V03