TFA Dostmann ST485 Operating Manual

Non-Contact Infrared Thermometers

ST485
Operating Manual

3p

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TABLE OF CONTENTS

INTRODUCTION………………………………………3
FEATURES……………………………………………3
WIDERANGEAPPLICATION ………………………… 4
SAFETY……………………………………………… 4
DISTANCE&SPOTSIZE……………………………… 5
SPECIFICATIONS…………………………………… 6
FRONTPANELDESCRIPTION……………………… 8
INDICATOR……………………………………………8
BUTTONS………………………………………………9
MEASURMENTOPERATION………………………… 12
BATTERYREPLACEMENT…………………………… 13
NOTES……………………………………………… 13
MAINTENANCE …………………………………… 17

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INTRODUCTION

Thank you for purchase of the IR Thermometer. This is
capable of non-contact (infrared) temperature
measurements at the touch of a button. The built-in laser
pointer increases target accuracy while the backlight LCD
and handy push-buttons combine for convenient, ergonomic
operation.
The Non-contact Infrared Thermometers can be used to

measure the temperature of objects’ surface that is improper

to be measured by traditional (contact) thermometer (such
as moving object, the surface with electricity current or the
objects which are uneasy to be touched.)
Proper use and care of this meter will provide years of
reliable service.

FEATURES:

 Rapid detection function
 Precise non-contact measurements
 Dual laser sighting
 Unique flat surface, modern housing design
 Automatic Data Hold
 ℃/℉ switch

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 Emissivity Digitally adjustable from 0.10 to 1.0
 MAX temperature displays
 Backlight LCD display
 Automatic selection range and Display Resolution 0.1º

C(0.1ºF)

 Trigger lock
 Set high and low alarms

WIDE RANGE APPLICATION:

Food preparation, Safety and Fire inspectors, Plastic
molding, Asphalt, Marine and Screen printing, measure ink
and Dryer temperature, HVAC/R, Diesel and Fleet
maintenance.

SAFETY

 Use extreme caution when the laser beam is turned on.
 Do not let the beam enter your eye, another person’s

eye or the eye of an animal.

 Be careful no to let the beam on a reflective surface

strike your eye.

 Do not allow the laser light beam impinge on any gas

which can explode.

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Distance & Spot Size

As the distance (D) from the object increases, the spot size
(S) of the area measured by the unit becomes larger. The
relationship between distance and spot size for each unit is

listed below. The focal point for each unit is 914mm (36”).

The spot sizes indicate 90% encircled energy.

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ST485

D:S= 20:1

D

S

20in.

2.0in @

10in.

1.0in @

50.8mm @

508mm

254mm

25.4mm @

1. SPECIFICATIONS

MODEL Temperature range D: S

ST485 -50 to 800 oC(-58℉ ~ 1472℉) 20:1
Display resolution 0.1 oC(0.1℉) <1000

1℉ >1000
Accuracy for targets:

Assumes ambient operating temperature of 23 to 25 oC (73
to 77℉)

-50 … -20℃(-58 t…-4℉): ±5℃(±9℉)

-20 … 538℃ (-4 … 1000℉): ± 2.0% or +2℃(±3.6℉);
538 … 800℃(1000 … 1472℉): ± 3.5% or ± 5℃(±9℉)

Repeatability

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-35~20℃(-31~68℉) : ±1.3℃(2.3℉)

20~800℃(68~1472℉): ±0.5% or ±0.5℃(0.9℉)

Response time 150ms
Spectral response 8~14um
Emissivity Digitally adjustable from 0.10 to 1.0
Over range indication LCD will show “----”
Polarity Automatic (no indication for positive polarity);

Minus (-) sign for negative polarity
Diode laser output <1mW,Wavelength 630~670nm,
Class II laser product
Operating temp. 0 to 50℃(32 to 122℉)
Storage temp. –10 to 60℃ (14 to 140℉)
Relative humidity 10%~90%RH operating,
<80%RH storage
Power supply 9V battery, NEDA 1604A or IEC 6LR61,
or equivalent
Safety “ CE ” Comply with EMC

Note:
 Field of View: Make sure that the target is larger than

the unit’s spot size. The smaller the target, the closer

you should be to it. When accuracy is critical, make

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sure the target is at least twice as large as the spot
size.

2. FRONT PANEL DESCRIPTION

① IR sensor
② LCD Display Laser

pointer beam

③ up button
④ down button
⑤ mode button
⑥ Measurement Trigger
⑦ Battery Cover
⑧ Handle Grip

3. INDICATOR

① Data hold
② Laser ” on” symbols
③ Lock symbol
④ High alarm and low alarm symbol
⑤ ℃/℉ symbol
⑥ Low power symbols
⑦ Emissivity symbol and value
⑧ Temperature values for the MAX
⑨ Symbols for MAX

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⑩ Current temperature value

4. Buttons

① Up button (for

EMS,HAL,LAL)

② Down button (for

EMS,HAL,LAL)

③ MODE button

(for cycling through the mode loop)

Functional Design

1. the switches of C/F sat in a cell switching

2. In the measuring time up, down keys to adjust the

Emissivity.

3. IN the hold time up keys to turn on or off the

laser
Down keys to turn on or off
the backlight

4. To set values for the High Alarm (HAL), Low Alarm (LAL)
and Emissivity (EMS), press the MODE button until the
appropriate code appears in the display, press the UP and
down buttons to adjust the desired values.

MODE Button Function

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Press the mode button
also allows you to access
the set
state,Emissivity(EMS),Lo
ck on/off,HAL on/off, HAL
adjustment LOW
on/off,LOW
adjustment,Each time you
press set you advance
through the mode cycle.
The diagram shows the
sequence of functions in
the mode cycle.
EMS adjustment. The
Emissivity(EMS) digitally

adjustable from 0.10 to 1.0, LOCK on/off. The lock mode

is particularly useful for continuous monitoring of
temperatures. Press the up button or down button to
turn on or off . Press the Measurement Trigger to
confirm the lock measurement mode. The ST485 will
continuously display the temperaure until press again

LOCK on/off

HAL on/off

HAL adjustment

LOW on/off

LOW adjustment

EMS adjustment

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the Measurement Trigger.

In lock mode, press the up button or down button
adjustable the Emissivity.HAL (LOW) on/off. Press
the up button or down button to turn on or turn off.
Press the Measurement Trigger to confirm the
High(Low)alarm mode.Hal(LOW) adjustment. The
high(Low) alarm adjustable form

ST485 -50 to 800 oC(-58℉ ~ 1472℉)

Switching C/F

Select the temperature units (oC or oF)
using the oC/oF switch ( ① )

Max indicate the max record that
displays between the pressing and releasing the "ON/OFF"
button each time

MEASUREMENT OPERATION

① Hold the meter by its Handle Grip and point it
toward the surface to be measured.

② Pull and hold the Trigger to turn the meter on and

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begin testing. The display will light if the battery is
good. Replace the battery if the display does not
light.

③ Release the Trigger and the HOLD display icon
will appear on the LCD indicating that the reading is
being held. In HOLD status, press the UP button to
turn on or off the laser. And press the DOWN button to
turn on or off the backlight.
④ The meter will automatically power down after
approximately 7 seconds after the trigger is
released.(Unless the unit is locked on)

Note: Measurement considerations

Holding the meter by its handle, point the IR Sensor
toward the object whose temperature is to be measured.
The meter automatically compensates for temperature
deviations from ambient temperature. Keep in mind that
it will take up to 30 minutes to adjust to wide ambient
temperatures are to be measured followed by high
temperature measurements, some time (several
minutes) is required after the low (and before the high)
temperature measurements are made.

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This is a result of the cooling process, which must take
place for the IR sensor.

5. BATTERY REPLACEMENT

① As battery power is not
sufficient, LCD will display

“ ” replacement with

one new battery type 9V is
required.

② Open battery cover,

then take out the battery from instrument and replace
with a new 9-Volt battery and place the battery cover
back.

6. NOTES:

 How it Works

Infrared thermometers measure the surface

temperature of an object. The unit’s optics sense

emitted, reflected, and transmitted energy, which is
collected and focused onto a detector. The unit’s
electronics translate the information into a temperature
reading, which is display on the unit. In units with a

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laser, the laser is used for aiming purposes only.

 Field of View

Make sure that the target is larger than the unit’s spot
size. The smaller the target, the closer you should be to
it. When accuracy is critical, make sure the target is at
least twice as large as the spot size.

 Distance & Spot Size

As the distance (D) from the object increases, the spot
size (S) of the area measured by the unit becomes
larger. See: Fig: 1.

 Locating a hot Spot

To find a hot spot aim the thermometer outside the area
of interest, then scan across with an up and down
motion until you locate hot spot.

 Reminders

① Not recommended for use in measuring shiny or

polished metal surfaces ( stainless steel, aluminum,
etc.).See Emissivity

② The unit cannot measure through transparent surfaces

such as glass. It will measure the surface temperature of
the glass instead.

③ Steam, dust, smoke, etc., Can prevent accurate

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measurement by obstructing the unit’s optics.

 Emissivity

Emissivity is a term used to describe the
energy-emitting characteristics of materials.
Most (90% of typical applications) organic materials
and painted or oxidized surfaces have an emissivity of

0.95 (pre-set in the unit). Inaccurate readings will result
from measuring shiny or polished metal surfaces. To
compensate, cove the surface to be measured with
masking tape or flat black paint. Allow time for the tape
to reach the same temperature as the material
underneath it. Measure the temperature of the tape or
painted surface.

Emissivity Values

Substance

Thermal
emissivity

Substance

Thermal
emissivity

Asphalt

0.90 to 0.98

Cloth (black)

0.98

Concrete

0.94

Human skin

0.98

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Cement

0.96

Lather

0.75 to 0.80

Sand

0.90

Charcoal
(powder)

0.96
Earth

0.92 to 0.96

Lacquer

0.80 to 0.95

Water

0.92 to 0.96

Lacquer
(matt)

0.97

Ice

0.96 to 0.98

Rubber
(black)

0.94
Snow

0.83

Plastic

0.85 to 0.95

Glass

0.90 to 0.95

Timber

0.90

Ceramic

0.90 to 0.94

Paper

0.70 to 0.94

Marble

0.94

Chromium
oxides

0.81

Plaster

0.80 to 0.90

Copper
oxides

0.78
Mortar

0.89 to 0.91

Iron oxides

0.78 to 0.82

Brick

0.93 to 0.96

Textiles

0.90

7. MAINTENANCE

 Repairs or service are not covered in this manual and

should only be carried out by qualified trained
technician.

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 Periodically, wipe the body with a dry cloth. Do not use

abrasives or solvents on this instrument.

 For service, use only manufacturer’s specified parts.