Extech 401021 Operating Manual

INSTRUCTION MANUAL

Models 401020 (Lux) and 401021 (Fc)

Light Meter Adapters

• Connects to standard DMM for

display

• Measures Tungsten,

Fluorescent, Sodium, Mercury,
and Daylight

• Status LED for power and low

battery

• Battery operated

1. INTRODUCTION

Congratulations on your purchase of Extech’s Light Adapter. This professional device, with
proper care, will provide years of safe reliable service.

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2. SPECIFICATIONS

2.1 Electrical Specifications

Accuracy
Sensor Exclusive photo diode & color correction filter

Operating
Temperature/humidity
Power Supply 006P DC 9V battery
Power Consumption Approx. 6 mA DC
Low battery indication Status LED on Front panel of Adaptor
Dimensions / Weight 3.9x1.9x1" (100x50x25mm) / 0.33 lbs. (150g)

2.2 Range Specifications

401020 401021
Range
1 0 to 2000 Lux 0.1mV per 1 Lux 0 to 200 Fc 1mV per 1 Fc
2 2000 to 20,000 Lux 0.1mV per 10 Lux 200 to 2000 Fc 0.1mV per 1 Fc
3 20k to 50k Lux 0.1 mV per 100 Lux 2000 to 5000 Fc 0.1mV per 10 Fc

2.3 Frequency Spectrum

3. FRONT PANEL DESCRIPTION

1 Power ON status LED

2 Low battery status LED

3 Power ON / Range select switch

4 Light sensor

5 Meter to sensor connect cable

6 DMM banana connector plugs

± (5% + 1mV)

Measurement

Output to DMM Measurement Output to DMM

spectrum designed to meet C. I. E.
32oF to 122oF (0C to 50oC) / <90% RH

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4. OPERATION

4.1 Insure that a fresh battery is installed in the adapter by moving the Power/Range
Select switch from the OFF position to one of the range select positions. If the Power
ON light doesn't glow or if the Low Battery LED does glow, check the battery.

4.2 Connect the adapter to the COMMON and VOLTAGE inputs of a multimeter via the
adapter's banana plugs. The polarity of the connection should be reversed if a negative
light level reading is indicated on the multimeter.

4.3 Set the mulitmeter to the mV or higher DC voltage position. Adjust the range to suit
your display needs. Do not use autorange if possible.

4.4 Select the maximum range via the Range Select Switch and move lower in range as
needed.

4.5 Hold the Light Sensor so that it faces the light source to be measured. The
multimeter's display will indicate light level readings. Refer to Sections 5 and 6 for
additional measurement considerations.

5. CORRECTION FACTOR FOR DIFFERENT TYPES OF LIGHTING

The light adapter is calibrated using a
precise "Standard tungsten light source

of 2856oK". If the meter is to measure
a different type of lighting, the
correction factor table, below, should
be applied to the readings. Multiply the
multimeter readings by the factors in
the right column for a particular lighting
type shown in the left column.

6. RANGE SELECTION

The meter has three measurement ranges (0-200, 0-2000, and 0-5000 Fc) or (0-2000, 0­20000, and 0-50000) Lux). The proper range selection will produce the most accurate
reading. Always select the range that produces the maximum number of digits without
exceeding the maximum count for that particular range. For example, a reading of 1456 Fc
should be read on the 0 - 2000 range, not the 0-5000 range.

7. BATTERY REPLACEMENT

When the Low Battery status LED glows, replace the battery as soon as possible. Open
the Battery Compartment by removing the rear screw. Remove the battery, replace it
with a fresh 9V battery and re-assemble the meter.

8. CALIBRATION / REPAIR SERVICES

Extech offers complete repair and calibration services for all of the products we sell. For
periodic calibration, NIST certification or repair of any Extech product, call customer
service for details on services available. Extech recommends that calibration be performed
on an annual basis to insure calibration integrity.

9. WARRANTY

EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects in parts and
workmanship for one year from date of shipment (a six month limited warranty applies on sensors and
cables). If it should become necessary to return the instrument for service during or beyond the warranty
period, contact the Customer Service Department at [phone] for authorization. A Return
Authorization (RA) number must be issued before any product is returned to Extech. The sender is
responsible for shipping charges, freight, insurance and proper packaging to prevent damage in transit.
This warranty does not apply to defects resulting from action of the user such as misuse, improper wiring,
operation outside of specification, improper maintenance or repair, or unauthorized modification. Extech
specifically disclaims any implied warranties or merchantability or fitness for a specific purpose and will not
be liable for any direct, indirect, incidental or consequential damages. Extech's total liability is limited to
repair or replacement of the product.
The warranty set forth above is inclusive and no other warranty, whether written or oral, is expressed or
implied.

Lighting Type Multiplication Factor

MERCURY LAMP x1.14
FLUORESCENT
LAMP
DAYLIGHT x1.00
SODIUM x1.22
METAL HALIDE x1.00

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x1.08

TYPICAL LIGHT LEVELS

Lux Foot

Candles

Lux Foot

Candles

Factories Home

20-75 2-7 Emergency Stairs, Warehouse 100-150 10-15 Washing

75-150 7-15 Exit/Entrance Passages 150-200 15-20 Recreational Activities
150-300 15-30 Packing Work 200-300 20-30 Drawing Room, Table
300-750 30-75 Visual Work: Production Line 300-500 30-50 Makeup

750-1,500 75-150 Typesetting: Inspection Work 500-1,500 50-150 Reading, Study

1,500-3,000 150-300 Electronic Assembly, Drafting 1,000-2,000 100-200 Sewing

Office Restaurant

75-100 7-10 Indoor Emergency Stairs 75-150 7-15 Corridor Stairs
100-200 10-20 Corridor Stairs 150-300 15-30 Entrance, Wash Room
200-750 20-75 Conference, Reception Room 300-750 30-75 Cooking Room, Dining

Table

750-1,500 75-150 Clerical Work 750-1,500 75-150 Show Window

1,500-2,000 150-2000 Typing, Drafting

Store Hospital

75-150 7-15 Indoors 30-75 3-7 Emergency Stairs
150-200 15-20 Corridor/Stairs 75-100 7-10 Stairs
200-300 20-30 Reception 100-150 10-15 Sick Room, Warehouse
300-500 30-50 Display Stand 150-200 15-20 Waiting Room
500-750 50-75 Elevator 200-750 20-75 Medical Exam Room

750-1,500 75-150 Show Window, Packing Table 750-1,500 75-150 Operating Room

1,500-3,000 150-300 Storefront, Show Window 5,000-10,000 500-1000 Eye Inspection

COMMON CONVERSION FACTORS

Illuminance (Visible Flux Density)

1 lm/m2 =

1 lux (lx)

10-4 lm/cm2

10-4 phot (ph)

9.290 x 10-2 lm/ft2

9.290 x 10-2 foot-candles

Luminance (Visible Flux Density per Solid Angle)

1 lm/m2/sr = 1 candela/m2
Luminous Intensity (Visible Flux per Solid Angle) 1 lm/sr = 1 candella
Luminous Flux ( Visible Flux) 1 lumen (lm) =

1.464 x 10-3 watts @ 555 nm

Copyright ©

1999 Extech Instruments Corporation. All rights reserved

including the right of reproduction in whole or in part in any form.

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