MIT GAL-2L-GAL-2H, GAL-3L User Manual

G O L D I L U X

L I G H T

M E T E R S

USER MANUAL

GAL - 2L, GAL - 2H,

GAL - 3L with GALP probes

GENERAL DESCRIPTION
EXTERNAL FEATURES AND CONTROLS
OPERATING INSTRUCTIONS
MAINTENANCE AND PRECAUTIONS
CALIBRATION
SPECIFICATIONS
WARRAN TY INF ORMATI ON

GENERAL DESCRIPTION

The GOLDILUX series of light meters are designed to
measure illuminance of the visible spectral radiation in the
units of lux or optionally in footcandles.
An external probe may be plugged into a light meter. In this
case the detector in the light meter is automatically
disconnected and the displayed reading corresponds to the
quantity and the units measured with the probe.

The liquid crystal display of the metres (GAL-2L, GAL-2H) is
auto ranging over one decade. External probes (e.g. GALP­1L) have a built-in probe gain selector switch with two
different gains and thus cover a wider measuring range than
the meters with built-in detector. The probe gain settings are
multiplied as indicated on the probe labels and the switch
setting indicated by the probe range factor. Probes
combined with a non-specific meter (display - GAL-3L) offer
the best combination with the widest possible measuring
range.

EXTERNAL FEATURES AND CONTROLS
Fig. 3 indicates the layout and function of the switches and
connectors and other features available on the light metres.

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The ON/OFF switch (A in Fig. 3) is located on the left side
of the meter housing. To switch ON move it forward. The
meter is OFF when the switch is in the lower position.

The HOLD button (B in Fig. 3) can be used to "freeze" the
display for convenient reading by the operator. This hold
button operation can be achieved for up to 5m distance
from the instrument by means of a remote hold cable
(optional extra) plugged into connector C in Fig. 3. A simple
contact closure between the two mono plug connector pins
activates the hold ("freeze") function.

The ANALOG OUTPUT of the meter is D in Fig. 3. It can be
used to supply a 2V output for a full-scale reading. It has an
output impedance of 10 k and can be used to record light
levels on a chart recorder or any other suitable data
acquisition system. A stereo plug should be used to
connect the equipment to the analogy output socket.

OPERATING INSTRUCTIONS

1. Remove the instrument from its case and mount or
place it in the desired measurement position.

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2. Switch on the instrument and check its zero with the
cap firmly on the detector. Should it be necessary to
adjust the meter reading to zero (e.g. for calibration
purposes) adjust it via the potentiometer accessible
through the latch opening in the open battery
compartment.

3. Remove the protective cap from the detector being
used.

4. Take readings. Check on the units (Kilolux or lux or
footcandles as indicated by the label).

N.B.: A 9V battery is necessary for operating the instrument
and this has to be inserted in the battery compartment at
the back of the meter as shown in Fig 3.

MAINTENANCE AND PRECAUTIONS
When not in use, always put the protective cap on the
detector and keep the instrument in a safe place.
There is a warning "battery low" on the LCD display when
the 9V battery needs to be replaced.
If necessary, clean the detector with a soft clean cloth or
tissue moistened with alcohol. Dry and polish lightly with a
dry tissue.

3

CALIBRATION

1) Meters
a) Meters with a built-in detector (e.g. GAL-2L): adjust the

meter reading to zero via the potentiometer accessible
through the opening in the open battery compartment.
and the cap firmly on the detector,

b) Expose meter to a known illuminance, emitted by a

light source of the type for which the calibration is
desired. Alternatively, produce a stable illuminance with
a suitable light source of the desired type and measure
it with a calibrated light meter.

c) Adjust the meter with the calibration adjustment (F in

Fig. 3) until it reads correctly.

d) Seal the hole (F in Fig. 3) with a suitable calibration

sticker.

2) Probes
a) Plug the probe into the meter. Set the probe’s range

selector switch (A in Fig 4) to the lowest setting.

b) With the dustcap firmly in place (D in Fig 4) check the

meter reading of zero. The potentiometer P5 indicated
on the rear label of the probe has been disabled.

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Return instrument for repair if zero reading cannot be

obtained.
c) Expose probe as in 1 b) above.
d) If required the reading is adjusted by turning the

potentiometer P1 as indicated on the rear label of the

probe, until the reading is correct.
e) Set the probe range factor to the highest range factor

and adjust P2 (as marked on the rear label) until a

reading of exactly 10 times lower is achieved than with

the selector switch in the lowest range factor setting.
f) For probes with integral dose option (e.g.GALP-2L) -

please refer to the manufacturer. This range has been

discontinued in favour of a microprocessor range of

instrumentation.
g) To make the adjustments on the potentiometers P1 and

P2 it is necessary to pierce the rear label of the probe.

Seal again with suitable plastic stickers after the

calibration is completed.

NOTE

: Calibrations should only be performed by

trained metrologists in a recognized calibration
laboratory.

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SPECIFICATIONS

Measurement

parameter : Illuminance
Dynamic range : 1:200 000.
Readout : 4½ digit LCD display.
Power source : 9V type PP3 battery. Battery life

approximately 200 hours for alkaline
battery

Detector : Silicon photodiode with photo-metric

filtering.

Angular
response : As indicated in Fig. 1 (nominal values).
Spectral
response : As indicated in Fig. 2 (nominal values).
Mass : Display unit : 220 g.
Accessories : Protective cover for detector,

instruction manual.

Re-calibration : Return unit to a recognized calibration

laboratory for re-calibration every 12-18
months (depending on frequency of
usage) or if calibration is in doubt for
any reason.

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CIE
parameters

**

:

V() match [f

1

'] <3%
UV response [u] <0.1%
IR response [r] <0.1%
Cosine response [f

2

] <1.5%
Linearity error [f

3

] <0.1%
Error of display
unit [f4] <0.1%
Temperature
coefficient [(T2=5OC)] <-0.2%/OC
Fatigue [f

5

] <0.1%
Modulated
radiation f7 <0.1%
Polarization f

8

<0.1%

Range change f

11

<0.1%
Crest factor C >2
Lower frequency
limit f

l

<40 Hz

Upper frequency

limit fu >50 kHz

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* International Commission on Illumination (CIE).
** In accordance with CIE publication 69 (1987),

"Methods of characterizing illuminance and
luminance meters".

Fig 1 Fig 2

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Fig. 3

Fig. 4

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WARRAN TY INF ORMATI ON

One (1) year limited warranty
The manufacturer warrants the light meters and probes against
defects in materials and workmanship for a period of one (1) year
from the date of original retail purchase (proof of purchase
required). If an approved distributor receives notice of such defects
during the warranty period, he will either, at its option, repair or
replace products which prove to be defective and receive a
replacement from the manufacturer.
Exclusions
The above warranty shall not apply to defects resulting from
improper or inadequate maintenance by the customer, customer­supplied software or interfacing, unauthorized modifications or
misuse, operation outside the environmental specifications for the
product, improper site operation and maintenance, an accident or
abuse.
Obtaining warranty service
To obtain warranty service, the products must be returned by the
purchaser to an approved distributor. Repair or replacement of the
instrument will be at the discretion of the technician at the
manufacturers. They have to be notified of the warranty claim and
the defective product returned to them. Replacement will be at no
charge if deemed to be necessary.
Shipping charges from the customer to an approved distributor
shall be to the account of the customer and shipping charges from

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the approved distributor to the manufacturer shall be paid by the
approved distributor.
The manufacturer shall pay for the return of the replacement
product to the approved distributor, who shall be responsible for the
shipping charges to the customer.
Warranty limitations
The manufacturer makes no other warranty, either expressed or
implied, with respect to these products. The manufacturer
specifically disclaims the implied warranties of merchantability and
fitness for a particular purpose. Some states or provinces do not
allow limitations on the duration of an implied warranty, therefore
the above limitations or exclusion may not apply to you. However,
an implied warranty of merchantability or fitness is limited to the
one (1) year duration of this written warranty.
This warranty gives you specific legal rights, and you may also
have other rights which may vary from state to state, or province to
province.
Exclusive remedies
The remedies provided herein are the customer's sole and
exclusive remedies. In no event shall the manufacturer be liable for
any direct, indirect, special, incidental or consequential damages,
whether based on contract, tort, or any other legal theory. Some
states or provinces do not allow the exclusion or limitations of
incidental or consequential damages, thus the above limitation or
exclusion may hot apply to you.

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