DIGITAL LIGHT METER

Dr. Lim Jac Fang

Occupational Health Doctor

Department of Health, Sabah

1994

CT Lutron LX-105

LIGHT METER

FEATURES

Microprocessor circuit ensure high accuracy an also provide special function and features

Super large LCD display with contrast adjustment for viewing angel.

Dual function display

Heavy duty & compact case

Record Minimum, Maximum & Average readings

Data Hold

Auto power off saves battery life

Operates from 9V battery

FEATURES (cont..)

RS 232 PC serial interface

Spectrum of photo sensor meets C.I.E

Wide range measurement both LUX & foot candle units

Relative % light measurement

User selectable lighting type (Tungsten, Fluorescent, Daylight or Mercury)

Zero adjustment by push button

GENERAL SPECIFICATIONS

Circuit – Custom one-chip microprocessor LSA circuit

Display – 13mm with contrast adjustment

Lighting type – Daylight, Tungsten, Fluorescent, Mercury

Measurement range – LUX 0- 50,000 LUX , 3 ranges

- Foot candle 0 – 5,000 ft-cd, 3 ranges

- Relativity – 0 – 1999%

Sensor – Photo diode & color correction filter

Memory – Max, Min and Average readings

Sample Time – Approx 0.4 sec

Zero Adj. – By push button

Power off – manual off or auto shut off (after 10 min)

GENERAL SPECIFICATIONS (cont…)

Data output – RS 232 PC serial

Operating temperature - 0°C - 50°C (32°F - 122°F)

Operating Humidity – Max 80% RH

Power supply - 06P DC 9V battery (heavy duty)

Weight – 335g/0.77IB (Included batteries)

Size – 180 x 72 x 32 mm (7.1 x 2.8 x 1.3 inch)

Accessories - instruction manual

- Sensor cover

DIGITAL LIGHT METER

2001

CT Lutron LX-105

LIGHT METER

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2

34

567

89 10

16

11

12

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14

151- Display

2- Power Off/On

3- Data Hold Button

4- LUX/FC Button

5- Memory Record Button

6- Memory Call Button

7- Light Source Button

8- Zero button

9- % Button

10- Range Switch

11- LCD contrast adjust

12- Light Sensor

13- Sensor cover

14- Light sensor plug

15- Light sensor input socket

16- RS-232 Output

17- Battery compartment cover

17

MEASURING PROCEDURE

Push Power Off/On Button

Zero Adjust Procedures1. Cover the light sensor-using the Sensor Cover

2. Slide the Range Switch to the 2000 LUX Position

3. Push the Zero Button-display will show zero values

4. Upon completion, remove the sensor cover

Select the desired measuring unit by pressing the LUX/FC Button

Determine the lighting type by pressing the Light Source Select Button

L= Tungsten, F= Fluorescent, S= Day Light, C= Mercury

Select the max. Range using the Range Switch

If display shows “- - - -”, it indicates an overload condition, select the next higher range

If display shows “- - - -”, it indicates an out of range, select the next lower range

Position the Light Sensor directly under light source

-On the 20000 LUX range, the last digit will be shown on the lower line of LCD display

-On 50000 LUX range, the last two digit will be shown on the lower line of LCD display

For example:-

On the 20000 LUX range, if display show

1562 LUX

0

Data Hold

During measurement, pushing the “Data Hold Button will hold the display values and the LCD will show “D.H” symbol

To cancel the Data Hold function, press the Data Hold Button, once more

Relative % light measurement

During measurement, press the “%” Button. The current measured value will indicated as 100%

All the subsequent measurement will be indicated as percentage, relative to the value when the button was pressed

The formula used is as shown below:The new light valuesThe light values when the % button was pressed X 100

To de-activated- press “%” Button

Data Record (Max., min & Average reading

The DATA RECORD function displays the max, min & Average readings.

To start the Data Record function, press the “Record Button” once

With the “REC” symbol indicated on display

C. Push the “CALL Button” once more – average (AVG) values

A. Push the “CALL Button” once - maximum values (max)

B. Push the “CALL Button” once again – minimum (Min) values

To de-activate the Data Record function, Press the “Record Button” once again

BATTERY REPLACEMENT

When the left corner LCD display show “LBT”

-spec measurement may still be made for several hours after low battery indicator appears before the instrument become inaccurate

THANK YOU FOR YOUR ATTENTION