Major tech MT941 User manual

MT941
Professional Multifunction
Enviroment Meter

2

1. Introduction …………………………………………………………………… 4
2. Features ………………………………………………………………………… 4
3. General Specifications …………………………………………………….. 5
4. Manometer Specification ….………………………..………………….… 5
5. Button Specifications …………………………………………………….… 6
6. Display Icon Description ………………………………………………….. 7
7. Changing Setup Options ……………………………………………….…. 8
7.1. Setup Options …………………………….……….............……. 8
7.2. Entering or exiting Setup …........…………………………….. 8
7.3. Changing a Setup Option …........…………………………….. 8
7.4. Temperature Unit …………........……………………….…….... 8
7.5. Light Unit ……………………........……………..……….……….. 9
7.6. Sound Unit ……………………........……………….....…………. 9
7.7. Offset ……………………………........…...........………..………. 9
7.8. Velocity Unit ……………….….........……………………….……. 10
7.9. Flow Unit …………………………........……..………….…….….. 10
7.10. Area Unit ………………………........……………….….……….. 11
7.11. Area Size ………………………........………….…….….….…… 11
7.12. Auto Power Off Mode ……………........………….……..…… 12
7.13. Measuring RH% &Temperature ……........…………….…. 12
7.14. Measuring K-Type Temperature ……….........….…………. 13
7.15. Measuring Sound ……………….…………........…………..... 13
7.16. Measuring Light ………………………………........…………… 13
7.17. Measuring Air Velocity & Air Flow ………........………….. 13
7.18. Holding the Displayed Reading ……………........………… 14
7.19. Viewing the MIN, MAX, and AVG Reading ….........…… 14
8. Replacing the Batteries ……………………………………………….…… 14
Contents Page
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1. Introduction
ŸThe 5 in 1 digital Multifunction Environment Meter has been
designed to combine the functions of a Sound Level Meter, Light
Meter, Humidity Meter, Temperature Meter and CFM/CMM Thermo-
Anemometer. It is an ideal Multifunction Environment Meter with
scores of practical applications for professional and home use.
ŸThe Sound level function can be used to measure noise in factories,
schools, offices, home, etc, checking acoustics of studios,
auditoriums and hi-fi installations.
ŸThe Light function is used to measure luminance in the field. It is
fully cosine corrected for the angular incidence of light. The light
sensitive component used in the meter is a very stable, long life,
silicon diode.
ŸThe Humidity/Temperature uses a humidity/semiconductor sensor
and K-type thermocouple.
ŸCFM/CMM Thermo-Anemometer is suitable for use in a wide variety
of applications, including plant maintenance operations,
environmental analysis, fume hood testing, and HVAC system
assessments.
2. Features
Congratulations on your purchase of the MT941 Professional Multifunction
Enviroment Meter
ŸLarge LCD display with backlight.
ŸMAX, MIN and AVG measurements.
ŸDisplay shows Sound, Light, K-Type Temperature, Humidity &
Temperature as well as Air Velocity & Air Flow simultaneously.
ŸElectronic Offset function allows compensation of thermocouple
errors to maximize overall accuracy.
ŸThe device measures air velocity, it features 5 selectable units of
velocity measure: m/s, ft/min, km/h, MPH, knots, and it features 2
selectable units of flow measure: CFM, CMM.
ŸEasy to set Area dimension (up to 6 points) for air flow
measurement.
ŸUSB interface, USB to UART Bridge Controller.
ŸLow battery indication, Auto Power Off (Sleep mode) adjustable.
4

Operating Conditions
Storage Conditions
Power Supply
Low Battery Indicator
Accessories
0 to 50 °C
-10 to 60 °C
1 x 9V Battery
Yes
9V Battery and K-Type temperature, humidity probe,
light probe, sound probe, anemo probe and carrying
case.
3. General Specifications
Function Range Resolution
Accuracy
Sound Level
Light
Humidity and
Temperature
K type
Temperature
Air Velocity
Air Flow
30dB-130dB
20000Lux
5%-98%RH
10~30°C
(50~86°F)
-30~9.99°C
(-22~50°F)
31~60°C
(88~140°F)
-99.9~99.9°C
(-148~212°F)
-100~-200°C
(-148~-328°F)
100~1372°C
(212~2502°F)
(0.40~30)m/s
(196~5900)ft/min
(3.6~108.0)km/h
(2.2~67.0)MPH
(1.9~58.0)Knots
(0~999900)CFM
(0~999900)CMM
0.1
0.1,1,10
0.1
0.1
0.01
1
0.1
0.1
0.1
0.001~100
0.001~100
0.1,1
0.1,1
±3.5dB at 94dB Sound level 1KHz sine wave
±(5+10d)
±3.5%RH
±1°C/±1.8°F
±3%±0.20m/s
±3%±40 ft/min
±3%±0.8 km/h
±3%±0.4 MPH
±3%±0.4 Knots
accuracy is function of velocity and area
±2°C /±3.6°F
± [1.5%rdg +2°C(3.6°F)]
± [1.5%rdg + 1°C (1.8°F)]
4. Manometer Specification
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1. Press the button to turn the meter ON/OFF.
2. Press the button to step through the maximum, minimum, and
average readings. To exit the MAN/MIX/AVG mode, press the button
for 2 seconds to return to normal operation.
3. Press the button to switch between the temperature (humidity
Probe) and the K-Type temperature settings in the primary.
4. Press the button to freeze or unfreeze the displayed readings. The
meter is in area setup option, press the button to change the station
of flashing digit.
5. Press the button to switch between the Light, Sound, Air Flow and
Humidity settings in the secondary display.
6. Press the button to turn on the backlight. Press it again to turn
off the backlight. Press the button for 2 seconds to start or exit
Setup. (See "Changing Setup Options.")
7. When secondary readings show the Sound, press the button to
switch between FAST and SLOW mode. When secondary readings show
the Light, press the button for 2 seconds to zero the Light. When the
meter is in Setup mode, press the button to enter a setup option and
press the button again to store the displayed setting in memory.
8. Press the button to change the units of the primary display. In Setup
mode, press the button to scroll to the Setup option you want to
change or press the button to increase the displayed setting.
9. Press the button to change the units of the secondary display. In
Setup mode, press the button to scroll to the Setup option you want
to change or press the button to decrease the displayed setting.
5. Button Specifications
HOLD
HOLD
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1. Temperature (Humidity Probe), K-Type Temperature and Air Velocity
modes are active in primary display
2. Area Indication
3. Light, Sound, Air Flow and Humidity Modes are active in Secondary
Display
4. The Secondary Display
5. Sound of Fast or Slow Mode
6. Data Hold Indicator
7. REC, MAX, MIN and AVG Indicators.
8. Units of Sound (dBA/ dBC) in Secondary Display
9. Units of Light (LUX/ FC) in Secondary Display
10. K-Type Temperature Offset Option, OFFSET Display.
11. Entering or Exiting Setup Mode
12. Multiplier (x 10 orx 100)
13. Units of Flow (CFM/CMM) in Secondary Display
14. Units of Humidity in Secondary Display
15. The Indication of Meter Communicating to PC
16. Units of Area
17. Units of velocity
18. Multiplier (x10)
19. Units of Temperature
20. Low Battery Indicator
21. Auto Power OFF Mode Indicators
22. The Primary Display
6. Display icons Description
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Use Setup to choose Temperature, Light, Sound, Air Velocity, Air Flow,
Area, K-Type offset and sleep mode setting. The meter stores the settings
in its memory.
Function
Temperature Unit
Function Function
TEMP Unit Set Temperature Unit (°C or °F)
Light Unit LIGHT Unit Set Light Unit (LUX or FC)
Sound Unit SOUND Unit Set Sound Unit (dBA or dBC)
Offset K-Type OFFSET K-type Temperature offset
Units of velocity VEL Unit Set Velocity Unit(five unit)
Units of Flow FLOW Unit Set Flow Unit (CFM or CMM)
Units of Area AREA Unit Set Area Of Unit (in² or cm² or ft²)
Size of Area AREA Size Set Area Of Measuring Air Flow
Sleep Mode SLP Yes or No
7.2. Entering or Exiting Setup
7. Changing Setup Options
7.1. Setup Options
When the meter is in Setup mode, the display shows SETUP
Press the button for 2 seconds to start or exit Setup.
7.3. Changing a Setup Option
7.4. Temperature Unit
To change the temperature unit, enter TEMP Unit setup
operation. Press the or button until the display show °C or °F.
Press the button, to store the new setting in the memory.
1. Press the or button to scroll to the setup option you want to
change.
2. Press the button to change the setting.
3. Press the or button until the setting you want to use appears on
the display. Press to store the new setting in the memory.
Note: Setup is disabled in MIN MAX/AVG mode.
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To change the Light unit, enter LIGHT Unit setup operation.
Press the or button until the display shows LUX or FC,
Press the button, to store the new setting in the memory.
7.5. Light Unit
To change the sound unit, enter SOUND Unit setup operation.
Press the or button until the display shows dBA or dBC.
Press the button, to store the new setting in the memory.
7.6. Sound Unit
The secondary display shows the temperature and the offset.
The primary display shows the offset. You can store individual offsets for
K-Type temperature. Press the or button to increase or decrease offsets.
Press the button, to store the new setting in the memory.
7.7. Offset
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To change the velocity unit, enter VELOCITY Unit setup operation.
Press the or button until the display shows the unit you want to change.
Press the button, to store the new setting in the memory.
7.8. Velocity Unit
To change the flow unit, enter the FLOW Unit setup operation.
Press the or button until the display shows CFM or CMM.
Press the button, to store the new setting in the memory.
7.9. Flow Unit
Note: ● m/s — meters per second ● km/h — kilometers per hour
● ft/min — feet per minute ● MPH — miles per hour
● knots — nautical miles per hour
Note: ● CFM (ft3/min) = Air Velocity(ft/min) x Area(ft2)
● CMM (m3/min) = Air Velocity(m/s) x Area(m2) x 60
● CFM: cubic feet per minute
● CMM: cubic meters per minute
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To change the area unit. Enter area Unit setup operation.
Press the or button until the display show the unit you want
to change.
Press the button store the new setting in the memory.
7.10. Area Unit
1. When the meter is in Setup mode, Press the or button to
scroll to the area size setup option.
2. Press the button. The secondary display shows the area number
and area unit. The primary display shows the area being used. Such
as "S-3", that is "the three number of area size setting", The
numbers change circularly from 1 to 6.
3. Press the or button to scroll and choose the area that you
want to change.
4. Press the button to indicate the area number with a flashing digit.
5. Press the or button to change the flashing digit from 0 to 9.
6. Press the button to change the station of flashing digit and
press the or button to change the number, the adjust order is
from right to left.
7. Press the button to store the new area in the memory.
7.11. Area Size
HOLD
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The meter will automatically shut off after 20 minutes of inactivity.
When the meter is in Setup mode, the display shows SETUP.
Press the or button to scroll to the " SLP " page.
Press the button to indicate "ON" or "OFF". Press the or button
until the setting you want to use appears on the display.
Press the button to store the new setting in the memory.
7.12. Auto Power off Mode
1. Connect the "RH% &Temperatures of Probe to the Probe Input
Socket.
2. Press the button to toggle showing the Temperature in the
primary display.
3. Press the button to toggle showing the humidity in the
secondary display.
4. Press the button to change the temperature units between °C
and °F.
7.13. Measuring RH% &Temperature
Note: ● On (sleep mode on)
● OFF (sleep mode off)
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1. Hold or attach the thermocouple(s) to the measurement location.
2. Press the button to toggle showing the K-Type Temperature in
the primary display.
3. Pressing the button will change the temperature units between
°C and °F
Note: The display shows "- - - -" when a thermocouple is not
connected.
The display shows OL or -OL (overload) when the temperature
being measured is outside the thermocouple's valid range.
7.14. Measuring K-Type Temperature
1. Press the button to toggle showing the Sound in the secondary
display.
2. Press the button to switch between FAST and SLOW mode.
3. Press the ▼ button to change the sound units between dBA
and dBC
7.15. Measuring Sound
7.16. Measuring Light
1. Connect the Light Probe to the "Probe Input Socket".
2. Press the button to change to the Light in the secondary
display.
3. If Light of Probe is closed, secondary readings of the Light number
is not "0.000", pressing the button for more than 2 seconds will
zero the light. The meter will reset and display " 0000 " from right
to left. 0.000 will be displayed.
1. Connect the sensor to the sensor input jack on the right hand side
of the meter.
2. Press the button to toggle showing the Velocity in the primary
display.
3. Place the sensor in the air current. The orientation, which
arrowhead falls on, is identical as air current (see blow picture).
4. Press the ▲ button to select the desired air velocity units.
5. View the air velocity readings on the the primary display.
7.17. Measuring Air Velocity & Air Flow
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1. Turn off the meter.
2. Loosen the screw and remove the battery cover.
3. Replace the 9V battery.
4. Replace the battery cover and tighten the screw.
8. Replacing the Batteries
8. If you want to change the area number after step 6.
Press the button for 2 seconds to start area setting option.
Press the ▲ or ▼ button to scroll to chose the area that you want
to change.
Then press the button to indicate that area number with a
flashing digit.
Press the ▲ or ▼ button to change the flashing digit from 0 to 9.
Press the button to change the station of flashing digit.
Press the ▲ or ▼ button to change the flashing digit.
The order is from right to left.
Press the button to show the air flow number.
6. Press the button to change the area in secondary display.
7. Press the button again to change the flow in the secondary
display.
1. Press the button to step through the maximum (MAX),
minimum (MIN), or the average (AVG) readings.
2. Press the button to show the MIN/MAX and AVG of air
velocity, Temperature (humidity probe), and K-Type Temperature.
3. Press the button to show the MIN/MAX and AVG of light,
sound, air flow and humidity value.
4. Press the button for 2 seconds to exit MAX/MIN/AVG mode.
Notes: HOLD, MIN/MAX/AVG and Setup can be used when measuring
7.19. Viewing the MIN, MAX, and AVG Readings
1. Press the button to freeze the readings on the display.
The display shows HOLD.
2. Press the button again to turn off the HOLD function.
7.18. Holding the Displayed Readings
HOLD
HOLD
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MAJOR TECH (PTY) LTD
T9 Industrial Village, Sam Green Road, 7
Tunney Ext. 9, , Elandsfontein
South Africa
P.O. Box 888, Isando 1600,
South Africa
Telephone: [phone]
National Contact Number: 08 61 62 5678
Sales Facsimile: [phone]
Admin Facsimile: [phone]
E-mail: [email protected]
www.major-tech.com