Pro's Kit MT-4617 User manual

MT-4617 Light Intensity Meter
User’s Manual
1st Edition,2018
© 2018 Prokit’s Industries Co., Ltd

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Introduction
Thank you for your purchase of the MT-4617 Light Intensity Meter
designed and manufactured by our company. This meter will with proper
use, provide years of reliable service; therefore, it is recommended that
the user read carefully the user manual before using the light meter and
keep it in right place for reference.
Open-package inspection
Upon receipt of the light meter, inspect it to ensure no damage happened
during shipping. If the user finds obvious damage or malfunction in
operation, please contact the supplier.
Safety information
Warning
Do not use the light meter in the environment full of dusts or having gas
substances and flammable steam substances!
Safety mark description
This manual contains basic information for MT-4617 safety operation and
maintenance. Please read carefully following safety information before
use.
Table 1: Safety information
Important information which the user
must read before using the light meter
Mark of conformity

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Table 2: Warning message
Warning
It indicates that incorrect operation will
lead to serious injury or even fatal
accidents
Notice
It indicates that incorrect operation or
negligence will lead to meter damage or
wrong measurement results, etc.
Tips
Operation suggestions or prompts
Operation considerations
User should observe the following notices to guarantee safe operation
and obtain optimum performance.
Preliminary check
Before initial use, please check if the light meter operates normally and if
it is damaged during storage and transportation. In case of any damage,
please contact the supplier.
Placement
Operation
environmen
t
-10～50℃(14～122°F)
<80%RH(non-condensed)
Storage
environment
-10～+50℃(14～122°F)
<70%RH(non-condensed)

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To avoid faults, please DO NOT place the light meter in following
environments:
3:Use
Notice
1. The operation temperature range for the light meter is -10-50℃
(14-122°F).
2. In order to avoid damage, especially falling accidents, handling and
use should be avoided during severe mechanical vibration.
3. The light meter can only be calibrated and repaired by professional
personnel.
4. Before each use, the opto-sensor of light meter should be checked for
damage and dust. Make sure the meter is in good, smooth and clean
condition. If one or more functions of the light meter are irregular or not
ready for operation, avoid using the meter.
5. During the operation of the light meter, the meter measurement value
should not be at OL for a long time.

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6. Keep the meter out of direct sunlight to guarantee its normal operation
and long-term service life.
7. If the meter is subject to effect of intensive electromagnetic field, its
functions will be affected.
8. Only use batteries specified in technical data.
9. Batteries should avoid dampness. If the low battery symbol appears on
the display, the user should replace batteries.
Tips
1. The sensitivity of the optical detector will be lessened due to operation
conditions or time. It is recommended to make periodic calibration to
maintain the basic accuracy.
2. Please keep original package for future mailing (such as for light
meter calibration).
Introduction
Product description
Whether you are a professional or amateur photographer, while shooting,
you pay more attention to the surrounding illuminance rather than the
setting, because this will help you take the best shot. Although the
illuminance can be estimated by the photographer, there is a difference in
perception between human and camera about the requirement for
supplementing illuminance. This difference will lead to a big contrast of
the expected image effect against the actual one. In the face of this, do
you wish to possess a light meter? When you intend to buy a house, you
require both good location and indoor brightness during the day. So, do
you wish to possess a light meter to measure the illuminance in every
corner of the house?

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With the progress of human civilization, more and more people
emphasize low carbon life.Architects tend to figure out how to bring more
natural light into the house while putting up a residential building.
However, in many cases, fluorescent lights will be used when the natural
light is not enough. In response to the slogan of energy saving and
emission reduction advocated by the state, we should use the fluorescent
lamps based on the actual needs. So, a professional and convenient light
meter can provide you with a reference regarding illuminance.
The MT-4617 Light Intensity Meter has a friendly human-machine
interface and can be activated by a simple press of keys. The buzzer
activates upon key press to notify that it is effective. This light meter is
able to measure the visible light produced by fluorescent lamp,
metal-halide lamp, high voltage sodium lamp or electric incandescent
lamp for a vivid and intuitive image display.
Outstanding features of the MT-4617 multi-function light meter
Automatic and manual range switching;
Inquiry function for maximum and minimum values;
Data hold function;
Peak value measurement function;
Relative value measurement function;
Zero calibration function;
3 1/2 bit LCD display, with analog bar display;
Fc/Lux unit conversion function;

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Outrange indication (When the measured value exceeds the current
range, LCD will display the signal “OL” to indicate that the range is
overreached);
High precision. Measurement range (0.00~200000Lux);
Low battery indicator;
Key tone and mute selection;
Auto power-off function (The machine will be powered off
automatically keys are not operated for more than 10 minutes)
Compact design, durable, and portable.
Name and function of components
Plan view

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1. Opto-sensor protection cover
2. Opto-sensor
3. LCD display screen
4. Compound key for main power and touch tone:
Power on/off: Short press the key to activate the instrument and long
press for 1 second to shut it down.
Touch tone on/off: Under working mode short press the key to turn the
touch tone on and off. Default is key with tone.
5. max and min values inquiry key
6. Lux/Fc unit conversion key
7. Compound key for data hold and zero calibration:
Data hold: Short press the key to enter/exit data hold mode.
Zero calibration: Long press for 1 second to perform Zero calibration
function.
8. Compound key for relative value and peak value measurement:
Relative value measurement: Short press the key to enter/exit relative
value measurement mode.
Peak value measurement: Long press for 1 second to enter/exit peak
value measurement mode.
9. Key for manual range switching: Short press the key for 20.00Lux 
200.0Lux 2000Lux 20000Lux 200000Lux (or 20.00Fc 
200.0Fc 2000Fc 20000Fc) circulation; Long press for 1 second to
exit manual range switching mode.

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LCD display interface
1. Prompt for manual range switching mode
2. Prompt for data hold mode
3. The analog bar shows the current measurement value information.
4. The digit shows the current measurement value information.
5. Lux unit
6. FC unit
7. Prompt for auto measurement mode
8. Prompt for peak value measurement mode
9. Prompt for low battery
10. Prompt for relative value measurement mode
11. Prompt for max and min values inquiry
2 Measurement methods
Notices prior to measurement
Warning
1: Do not use the light meter in environments full of dusts or having gas
substances and flammable steam substances!
2: Do not use the light meter for measurement in the place with high
temperature and high humidity.

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3: Do not use the light meter in environments with intense infrared or
ultraviolet rays!
Tips
1: The opto-sensor of this meter is designed by simulating the sensitive
curve of light obtained through human eyes. The spectral coverage is
between 320mm and 730mm. When it is used for measurement within
the infrared range, there will be a large data deviation.
2: The opto-sensor is calibrated by common electric incandescent lamp
required by CIE under the color temperature of 2854°K; the provided
reading number may be different for the spectrum of other lamps.
3: The reference level of light source test is at the top of the spherical
surface illuminated.
4: The optical detector should be exposed to light for 2 minutes before
measurement.
5: Influence of tester's shadow and other factors on the optical detector
should be avoided.
Action principles
Concepts of illuminance scales
One lux (lumen) indicates the illuminance from a surface of one square
meter, all points of which are one meter from a uniform source of one
candela.
One foot-candle (Fc) indicates the illuminance from a surface of one
square foot, all points of which are one foot from a uniform source of one
candela.

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Unit conversion for illuminance scales
1 Fc = 10.764 Lux
1 Lux = 0.09290 Fc
Conversion formula for illuminance and light intensity
E = I / r 2
Wherein E --- illumination value (Unit: Lux)；
I --- Light intensity of the light source（Unit: cd）；
r --- Distance from the luminous surface of light source to the optical
detector (Unit: m）.
During the measurement, the minimum distance between the luminous
surface of light source and the opto-sensor should be more than 15 times
greater than maximum size of the luminous surface (or opto-sensor).
Typical practice cases
Remove the protection cover of the MT-4617 multi-functional light meter
sensor and place it at right angle to the light source.
Press and hold the MT-4617 power key ④for a short time to power on
the light meter. The LCD screen will illuminate（about 5 seconds）with the
buzzer beeping twice, and “AUTO” will appear on the middle of LCD
display. This indicates that the auto measurement mode is ON.
Press and hold the manual range switching key ⑨of the MT-4617 for a
short time, “MANU” will appear on the top left position of the LCD display,
indicating that the manual range switching mode has been activated. In
this mode, each time press and hold the key for a short time, the meter
will switch to 20.00Lux —>200.0Lux —>2000Lux —>20000Lux
—>200000Lux (or 20.00Fc—>200.0 Fc—>2000 Fc—>20000 Fc) in
sequence; pressing the key for one second will result in the inscription
“MANU” disappearing from top left position of LCD display, replaced by
“AUTO” appearing in the middle, to indicate that the meter has switched
the manual range switching mode to the auto range switchover.

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Press and hold the REL/PEAK key ⑧of the MT-4617 for a short time,
“REL” will appear on the top left position of the LCD interface, indicating
the activation of the relative value measurement mode. Press and hold
the key ⑧for a short time again, the device will exit the relative value
measurement mode and return to the original measurement mode, and
“REL” on the top left position of the LCD interface will disappear; pressing
the key for one second will lead to the peak measurement mode, “PEAK”
and “MANU” will appear on top right position of LCD display; press and
hold the key for one second once again, “PEAK” will disappear from the
top right position of the LCD interface, and “AUTO” will appear in the
middle of LCD, and the mode will return to auto measurement mode.
Press and hold max/min value inquiry key for a short time, “MAX” will
appear on top position of LCD interface, switching the device to the
max/min value inquiry mode; in this mode, each short press of the key
causes the mode to change from MAX to MIN or from MIN to MAX; press
and hold the “MAX/MIN” key ⑤for one second, “MAX/MIN” on top
position of the LCD interface will disappear, and the mode will exit. Press
and hold the data hold/zero calibration key ⑦of the MT-4617 for a short
time to enter the data hold mode, which will be indicated by the apparition
of “HOLD” on the top left position of the LCD interface; press and hold the
key for a short time once again, “HOLD” will disappear from the top left
position of the LCD interface, and the device will exit the data hold mode.
In any mode with sensor covered, press and hold data hold/zero
calibration key ⑦for one second, “ADJ” will appear on the LCD interface,
and the device will enter the zero calibration mode: several seconds later
“ADJ” will disappear from the LCD interface, and the device will exit the
data hold mode and return to auto measurement mode.

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Tips
1: The reference position of light source test is at top of sphere surface
under light.
2: In various measurement modes, analog bar in the middle of the LCD
screen will change with figures of Nixie tubes.
3: When reading, existing data can be locked by pressing and holding
“HOLD/ZERO” key for a short time;
4: In zero calibration mode, the opto-sensor must be covered by
opto-sensor visor before calibration.
5: After completing the test, the sensor protection cover should be put
back to protect light filter and sensor.
Specific Application
Application of manual switchover of range measurement mode
Press and hold the RAN key (range manual switchover key) for a
short time, “MANU” will appear on the top left position of the LCD
interface, and the meter will enter the manual switchover
measurement mode (as shown in figure 3-1-1);
When entering manual switchover of range function, press RAN key
for a short time each time, it will switch to 20.00Lux—> 200.0Lux—>
2000Lux—>20000Lux—>200000Lux (or 20.00Fc—> 200.0
Fc—>2000 Fc—>20000 Fc) in sequence;
Press and hold RAN key for one second, “MANU” on the top left
position of the LCD interface will disappear, and “AUTO” will appear
in middle of LCD interface, and manual range switchover function will
exit and the device will return to auto range switchover mode;

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Figure 3-1-1 20.00Lux interface
200.0Lux interface 2000Lux interface
20000Lux interface 200000Lux interface
Tips
1: Only in peak value measurement mode, relative value measurement
mode and max/min value inquiry mode, will it be effective to press RAN
key for a short time.

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2: In relative value measurement mode and max/min value inquiry mode,
press and hold the key for one second, it will return to auto switchover
of range.
3: In peak value measurement mode, data hold mode and zero calibration
modes, it will be effective to press and hold RAN key for a long time.
4: In this mode, when measurement value exceeds present range, “OL”
will appear on LCD interface to indicate over-range, and the user
should switch over the measurement range at this time.
Application of relative/peak value measurement mode
Press and hold REL/PEAK key for a short time (composite key for
relative/peak value measurement), “REL” will appear on the top left
position of the LCD interface (as shown in figure 3-1-2A), and the
device will enter the relative value measurement mode;
Press and hold REL/PEAK key for a short time again, “REL” on the
top left position of the LCD interface will disappear, and the device
will exit the relative value measurement mode and return to original
measurement mode;
Press and hold “REL/PEAK” key for one second, the device will enter
the peak value measurement mode, “PEAK”LCD will appear on the
top right position of the LCD interface, and at the same time, “MENU”
will appear on the top left position of the LCD interface (as shown in
figure 3-1-2B);
Press and hold the key once again for one second, “PEAK” on top
right position of LCD interface will disappear, and “AUTO” will appear
on the middle of LCD interface, and the device will exit the peak
value measurement mode and return to auto measurement mode (as
shown in 3-1-2C).

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Figure 3-1-2A Figure 3-1-2B Figure 3-1-2C
Tip
1: Only in auto measurement mode, peak value measurement mode,
max/min value inquiry mode and data hold mode, it will be effective to
press and hold REL/PEAK key for a short time.
2: In non-zero calibration mode, press and hold “REL/PEAK” for one
second, the device will enter the peak value measurement mode.
Application of maximum/minimum value inquiry mode
Press and hold “MAX/MIN” key for a short time, “MAX” will appear on
top LCD interface (as shown in figure 3-1-3);
In max/min value inquiry mode, press “MAX/MIN” key once, you will
switch MAX to MIN or MIN to MAX;
Press and hold “MAX/MIN” for one second, “MAX/MIN” on top LCD
interface will disappear, and the max/min value inquiry mode will exit.
Figure 3-1-3

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Tips
In non-zero calibration mode, press and hold “MAX/MIN” key for a short
time to use the max/min value inquiry functions;
Application of data hold and zero calibration mode
Press and hold “HOLD/ZERO” key for a short time, “HOLD” will
appear on the top left position of the LCD interface (as shown in
3-1-4A), then the device will enter the data hold mode;
Press and hold the key again, “HOLD” on the top left position of the
LCD interface will disappear, and the meter will exit the data hold
mode;
Cover the opto-sensor with the visor, and press and hold
“HOLD/ZERO” key for one second, “ADJ” will appear on LCD
interface (as shown in figure 3-1-4B), then the device will enter the
zero calibration mode. Several seconds later, “ADJ” on LCD
interface will disappear, and zero calibration mode will
automatically exit and return to auto measurement mode.
Notice
Before zero calibration, the opto-sensor must be covered with the
opto-sensor visor.
. Figure 3-1-4A Figure 3-1-4B

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Tips
1. In non-zero calibration mode, press and hold “HOLD/ZERO” key for
a short time to enter the data hold mode.
2. Zero-calibration can be made in any mode.
Other Functions
Auto power-off
If there is no action on keys of the MT-4617 for a long time, the meter will
automatically power off about 10 minutes later.
Technical Data
‧Temperature range:
Operation:-10～50°C, max 80 % HR（Non-Condensed）
Storage:-10～50°C，max 80 % HR (Non-Condensed)
(removing batteries)
‧Sampling rate: ≥2 times/s。
‧Display: 3½ digits, max reading of 1999, with analog bar display;
‧Sensor: silicon photoelectric diode
‧Measured spectral range: 320～730nm
‧Measurement ranges: 20, 200, 2000, 20000, 200000, Lux20, 200,
2000, 20000 FC
‧Operating environment: indoor use
‧Height: 2000m highest
‧Battery life: Approx. 200 hours
‧Power supply: 1×9 V，IEC 6LR61
‧Dimensions (H×W×D): 170 mm×85 mm×45 mm
‧Accuracy: ±3% (calibrated with incandescent lamps in 2854K) ±6%
other visible light source

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Cosine angle deviation characteristics
Cosine angle
Deviations
30°
±2%
60°
±6%
Tips: cosine angle is corrected in accordance with JIS C 1609:1993 and
CNS 5119 Grade A General Specification.
‧Luminous sensitivity characteristics:
Maintenance and Service
Service
Notice
When the meter seemingly fails during operation, following steps should
be followed to check the fault problem:
1: Check batteries. If “ ” appears on the LCD display, batteries
should be replaced.
2: Repair on the meter should be performed by service centers or other
qualified service professionals.
Cleaning
First wipe the meter with a damp soft cloth with clean water or neutral
detergent and then with a dry cloth.
Notice
1: Please make sure the light meter is turned off before cleaning.

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2: Do not use benzene, alcohol, acetone, ethyl ether, ketones, thinners
and gasoline, etc. in cleaning, because they will transform or fade the
light meter.
3: The light meter can only be used again when it is completely dry after
cleaning.
Battery replacement
If the battery symbol appears on the LCD accompanied by buzzer alarm,
batteries must be replaced.
Batteries should be replaced as follow:
Turn off the meter;
Remove the screw on the back of the meter and open the battery
compartment;
Remove exhausted batteries;
Replace new batteries observing polarity;
Replace the battery compartment cover and secure the
compartment screw.
Warning
1: Do pay attention to the right polarity of battery when putting in or
replacing batteries. In case of polarity reversal, the light meter will be
damaged, and can even cause explosion or fire.
2: Never connect one polarity of the battery to the other one with wire, nor
throw batteries into fire, or it will cause an explosion.
3: Do not attempt to dismantle the battery! The battery’s intensively
alkaline electrolyte is corrosive and endangers the user. In case of
contact of the electrolyte with skin or clothes, immediately rinse
touched parts with clean water; in case of contact of the electrolyte with
eyes, immediately rinse eyes with clean water and seek medical
advice.
Notice
1: The light meter should be turned off before replacing batteries.