Gossen MetraWatt MAVO-SPOT 2 User manual

Operating Instructions
MAVO-SPOT 2 15365
Digital Luminance Meter with 1° Measuring Angle 2/05-13

2GOSSEN Foto- und Lichtmesstechnik GmbH
Table of Contents Page
1 Applications 3
2 Display Panel and Keys
2.1 The Display Panel and its Elements 5
2.2 The Keypad 6
3 Working with the MAVO-SPOT 2
3.1 Preparation 6
Replacing the Batteries 6
Self-Test 7
Battery Indicator 7
The Protective Filter 7
3.2 Changing Default Settings (DIP) 8
Unit of Measure, cd/m² or fL 8
Modes: Standard and Compact 8
Memory Display: Individual or Groups 9
4 Operation
4.1 Switching the Instrument On 9
4.1.1 Display On-Time 9
4.2 Measurements 10
4.2.1 Overflow / Underflow Display 10
4.3 Reference Quantity Measurement 11
4.3.1 Ratio A/B 12
4.3.2 Percentage Deviation %A 13
4.3.3 Difference A-B 14
4.4 Setting Correction Factors 16
Table of Contents Page
4.5 Memory Function 19
4.5.1 Saving Measured Values 19
4.5.2 Editing Measured Values 20
4.5.3 Saving Values with Correction Factor21
4.5.4 Reading Out Measured Values 21
4.5.5 Clearing Memory 21
4.5.6 Saving Measured Values (in groups) 22
5 Additional Applications 23
5.1 Contact Measurement Attachment 23
5.2 Stationary Use 23
6 PC Software –USB Port 23
7 Accessories
7.1 Included Accessories 24
7.2 Optional Accessories 24
7.3 Calibration Certificate 25
8 Service Notes 25
9 Technical Data 26
Declaration of Conformity

GOSSEN Foto- und Lichtmesstechnik GMBH 3
1 Applications
The MAVO-SPOT 2 is a high-precision measuring instrument with a measuring angle of 1°. Luminance
measurements at distances of 1 meter to infinity can be performed with the instrument. The MAVO-SPOT 2
features mirror reflex optics with a 15° field of view, a sharply marked 1° measuring circle at the center and a
focusing mechanism.
The close-up lenses available as accessories make it possible to shorten measuring distance to 34 cm. Luminance
can be measured directly at displays with the help of the attachment for contact measurements.
The light sensitive sensor is color corrected, that is its spectral sensitivity is matched to the spectral luminous
efficiency of the human eye in daylight V(). Classification of luminance meters is specified in DIN 5032, part 7, and
in DIN EN 13032, appendix B. The MAVO-SPOT 2 fulfills class B requirements in accordance with these
standards. The instrument is equipped with a measured value memory module with up to 1000 memory locations
which can be read out and processed either directly via the keypad and display, or via the integrated USB port with
the help of the included standard software.
Suitable for the measurement of, for example:
Monitors in consideration of ambient light,
for example approval and consistency testing in the field of medical
technology in accordance with DIN 6868-57 and IEC 61223-2-5 (quality
assurance guideline dated 20 Nov. 2003)
Street, tunnel and airport illumination
Illumination at sports facilities
Contrast measurements at workstations (ASR)
Illumination in museums and public buildings
Projection screens (inspection for uniform illumination)
Warning: Do not perform measurements with the instrument pointed towards sun.
Eye damage may result, and the light sensor could be damaged as well.

4GOSSEN Foto- und Lichtmesstechnik GmbH
Lens with protective
filter or close-up lens
and baffle
Focus ring
USB -
connector
Battery compartment
Tripod socket
Eyepiece with cup
Control panel
Photo of MAVO-SPOT 2

GOSSEN Foto- und Lichtmesstechnik GMBH 5
2 The Display Panel
2.1 The Display Panel and its Elements
1Memory location display
2Measured value and memory display
3Unit of measure
4Symbol for correction factors 1 and 2
5Difference symbol
6Ratio symbol
7Percentage deviation symbol
8Calculated value, memory group
9Plus or minus sign for calculated value
10 Low battery warning display
11 USB indicator
12 Measuring function
13 Correction factor function
14 Measured value memory function
15 Ratio function
16 Percentage deviation function
17 Difference function

6GOSSEN Foto- und Lichtmesstechnik GmbH
2.2 The Keypad
3Working with the MAVO-SPOT 2
3.1 Preparation
Inserting the Batteries
The battery compartment is located at the front of the grip. Push the battery compartment
cover in the grip down. Remove the battery holder with the help of the tab. Replace the
batteries assuring correct polarity (+ and -). Insert the battery holder into the instrument
and close the battery compartment with its cover.
Approximately 5000 measurements can be performed with a new set of batteries.
Attention: Use new batteries only in accordance with IEC LR6 (2 ea. 1.5 V, AA).
Measuring key
Function key
(Lumi –Corr –Mem)
Measuring key
Function / shift key
(A/B –%A –A-B)
Multifunction key (MFK)

GOSSEN Foto- und Lichtmesstechnik GMBH 7
Self-Test
After inserting the batteries, the microcomputer executes a self-test. All of the elements
included in the display panel appear at the display during this test. The display test can
be aborted by pressing any key.
Battery Indicator
The MAVO-SPOT 2 requires two 1.5 V AA batteries (alkaline manganese). The capacity display indicates the
current battery power level. Measured values are retained in memory when the batteries are changed.
= The batteries are fully charged.
= The batteries are partially discharged –be prepared to replace them.
= The batteries are depleted and must be replaced as soon as possible.
The Protective Filter
Screw the included protective filter or one of the close-up lenses or the attachment for
contact measurements (optional accessory) onto the lens of your MAVO-SPOT 2.
Either the protective filter, a close-up lens or the attachment for contact
measurements (optional accessory) must always be used.

8GOSSEN Foto- und Lichtmesstechnik GmbH
3.2 Changing the Default Settings
You can change the default settings for your MAVO-SPOT 2. The settings are selected with the
help of the DIP switches inside the battery compartment underneath the battery holder. The
default settings can be changed as desired in any combination.
Stand. - Comp. DIP switch –selection of standard or compact operating mode
The operating mode can be changed from standard to compact with the Stand. - Comp. DIP
switch. You can perform measurements and save measured values in the compact mode –the
calculation and correction values functions (Corr) are disabled; programmed correction values
are nevertheless taken into account (see also section 4.4 on page 16).
cd/m² - fL DIP switch –selection of a of a unit of measure: cd/m² or fL
The desired unit of measure, namely candelas per square meter or foot-lamberts, can be selected with the
cd/m² - fL DIP switch.

GOSSEN Foto- und Lichtmesstechnik GMBH 9
Linear - Page DIP switch –selection of 1000 individual memory locations or subdivision into groups (see
also section 3.5.2 on page 19)
You can select either consecutive storage of 1000 measured values or subdivision into 10 groups with 100
measured values each with the Linear - Page DIP switch. The pages are identified as P-01 through P-10.
Memory content is deleted automatically when the memory location display mode is switched.
4 Operation
4.1 Switching the Instrument On
The MAVO-SPOT 2 can be switched on by pressing any key.
The measuring instrument is activated and the display panel is illuminated.
The last measured values appear at the display (display memory).
4.1.1 Display On-Time
If none of the keys at the MAVO-SPOT 2 are activated for a period of 30 seconds, the instrument is switched off
automatically, i.e. the display goes blank but measured values and individual settings are stored to memory.

10 GOSSEN Foto- und Lichtmesstechnik GmbH
4.2 Measurements
Press the key to select the Lumi function.
Look through the eyepiece on the MAVO-SPOT 2, and sharply focus
your measuring field with the focusing mechanism at the lens. Now
align the measuring circle reflected into the viewfinder to the point to be
measured. This point should be uniformly illuminated, and as large as
possible relative to the measuring circle.
Press the key and read the measured value.
.
4.2.1 Overflow / Underflow Display
If the measuring range is exceeded, “----” appears at the display.
If the measuring range is fallen short of, “0.00” appears at the display.

GOSSEN Foto- und Lichtmesstechnik GMBH 11
4.3 Reference Quantity Measurement
You can compare two measured values with your MAVO-SPOT 2.
Press the key in order to select the Lumi function to this end.
Acquire measured value A as described in section 4.2; measured value A is used as a reference value for the
following functions.
Press the key in order to select the A/B, %A or A-B function.
Now align the measuring circle to the second point.
Press the key; the calculated value for the respective function appears at the upper part of the display.
.
After acquiring measured value B, calculated value A/B, %A or A-B can be displayed by pressing the key.

12 GOSSEN Foto- und Lichtmesstechnik GmbH
4.3.1 Ratio A/B
This function is used, for example, for contrast measurements and luminance distribution at workstations.
The larger of the two measured values is always used as a dividend; i.e. if measured value B is larger than
measured value A, the ratio of the two measured values is calculated as B ÷ A.

GOSSEN Foto- und Lichtmesstechnik GMBH 13
4.3.2 Percentage Deviation %A
This function is used, for example, for testing monitor screen uniformity (percentage deviation of screen corners
from the reference value at the middle of the screen).
Depending upon the respective results, the minus sign (-) must be observed.
etc.

14 GOSSEN Foto- und Lichtmesstechnik GmbH
4.3.3 Difference A-B
You can read the difference between reference value A and the second measured value (B) directly from the
display. This function is used, for example, for detecting deviations in manufacturing.
Depending upon the respective results, the minus sign (-) must be observed.
etc.

GOSSEN Foto- und Lichtmesstechnik GMBH 15
You can switch back and forth between measured values A and B with the MFK.
The reflectivity of ceilings, walls and floors can be measured with the MAVO-SPOT 2 in combination with the
reflection standard (optional accessory). Estimations made with reflection or gloss panels are thus eliminated.
The reference value is measured against the reflection standard by pressing the key in order to ascertain
reflectivity.
Further measurements executed with the key indicate deviation as a percentage at the upper portion of the
display.
etc.

16 GOSSEN Foto- und Lichtmesstechnik GmbH
4.4 Setting Correction Factors
As many as two different correction factors can be entered to the MAVO-SPOT 2.
As default values, Corr1 is set to a factor of 1.000 (no correction) and Corr2 to a factor of 3.142 (illuminance
measurement with GOSSEN reflection standard, optional accessory).
Press the key to select the Corr function.
Select the desired correction factor with the MFK (visible at the top of the display).
While setting the factor, any measured value shown in the display is correspondingly adjusted (visible at the
bottom of the display).
You can switch back and forth between correction factors 1 and 2 with the key.

GOSSEN Foto- und Lichtmesstechnik GMBH 17
With the Corr2 function (factor of 3.142) and the GOSSEN reflection standard (optional accessory), you can
indirectly measure illuminance (lux or footcandles) with your MAVO-SPOT 2.
The unit of measure is switched to illuminance (lx or fc) at the display while measurement is being performed.
The factor 3.142 is the relationship between illuminance (E) and luminance (L) for a perfect reflecting diffuser
LE *
 
For a real diffuser (like GOSSEN reflection standard) where reflectance is less than 100%, Corr2 must be
adjusted to the actual value. Use the specific value delivered with your standards calibration protocol.
You can’t change Corr factors permanently until you have cleared the entire memory. This precaution is for
preventing a mixup of measurements with different Corr factors in memory.
The individual factor is saved to correction memory by pressing the key.
The correction factor is now applied to all measured values shown at the
display, which can be saved to memory as well.
The Corr symbol appears at the upper right hand corner of the display panel
in order to indicate a programmed correction factor.

18 GOSSEN Foto- und Lichtmesstechnik GmbH
Save Corr changes permanently
Take readings with applied corr factors
Reset correction values to factory defaults by simultaneously pressing the and keys.
!!!!
Clear
Memory
first !!

GOSSEN Foto- und Lichtmesstechnik GMBH 19
4.5 Memory Function
In addition to its display memory, the MAVO-SPOT 2 is also equipped with a measured value memory with 1000
memory locations. This function allows you to perform measurements on-site, and to read them out at a later point
in time. Stored values are retained when the instrument is switched off, as well as when the batteries are replaced.
4.5.1 Saving Measured Values (basic function)
Press the key to select the Mem function.
Perform measurement as described in section 4.2.
The displayed value is saved to memory by pressing the key. STO (stored) appears briefly at the memory
location display. In addition to the stored value, the number of the memory location is also displayed. Each
additional stored value is saved to the next successive memory location and is assigned the next consecutive
location number. FULL appears at the display when measured value memory is full. It is not possible to save a
single measured value twice.
etc.

20 GOSSEN Foto- und Lichtmesstechnik GmbH
4.5.2 Editing Measured Values (Mem-Edit)
Stored measured values can be overwritten with the Mem function.
Select the memory location to be edited with the MFK.
Press the key in order to freeze the memory location.
“Edit” and the selected memory location is shown in the display
indicating that you are up to overwrite the current mem-cell
Acquire the new measured value as described in section 4.2.
The displayed value is saved to memory by pressing the key.
The memory location display jumps to the last stored measured value.