MARTINDALE DT85 User manual

DT85 DIGITAL THERMOMETER
Instruction
Manual
Check out what else you can get from Martindale:
Martindale Electric Company Limited
Metrohm House, Penfold Trading Estate, Imperial Way, Watford WD24 4YY, UK
Tel: [phone] Fax: [phone]
E-mail: [e-mail]
Website: www.martindale-electric.co.uk
© 2014 Martindale Electric Company Ltd.
Registered in England No. 3387451. E. & O.E. LITDT85 Document Rev1
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ALWAYS READ THESE INSTRUCTIONS BEFORE PROCEEDING
Thank you for buying one of our products. For safety and a full
understanding of its benefits please read this manual before use.
Technical support is available from 01923 441717 and
[e-mail].
CONTENTS
1 Safety Information 1
1.1 Meaning of Symbols and Markings 1
1.2 Precautions 2
2 Introduction 3
2.1 Inspection 3
2.2 Description 3
2.3 Accessories 3
2.4 Battery Installation 3
3 Operation 4
3.1 Low Battery Indication 4
3.2 Description of Press Buttons 4
3.3 Description of LCD Symbols 4
3.4 Power On/Off 5
3.5 Auto Power Off 5
3.6 Backlight 5
3.7 Set Mode 5
3.8 Measurement Mode 7
3.9 Relative Mode 7
3.10 Hold Mode 8
4 Maintenance 9
4.1 Battery Replacement 9
4.2 Calibration 9
4.3 Cleaning 9
4.4 Repair & Service 10
4.5 Storage Conditions 10
5. Warranty 11
Specifications
Specification
DT85
Digital thermometer
GENERAL
Display: liquid crystal display
Polarity: automatic, positive implied, negative polarity indication
Measurement rate: once per second
Power: 2 x 1.5V, AAA alkaline batteries (IEC LR03, NEDA 24A)
Continuous operating time: 250 hours approx.
Low battery indication: the symbol is displayed when the battery voltage
drops below the operating level
Auto power off: after approx. 10 minutes
Dimensions: 132.9(L) x 50.9(W) x 24.7(D) mm
Weight: 148g approx. including batteries
Includes: 2 x K-Type thermocouples, detachable carry strap, 2 x 1.5V AAA
batteries, protective cover and instructions
ENVIRONMENTAL
Operating environment: 0°C to 50°C, <70% R.H.
Storage environment: -20°C to 60°C, < 80% R.H. with batteries removed.
EMC
Conforms to BS EN61326-1
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1
1 SAFETY INFORMATION
REMEMBER: SAFETY IS NO ACCIDENT
These instructions contain both information and warnings that are
necessary for the safe operation and maintenance of this product. It
is recommended that you read the instructions carefully and ensure
that the contents are fully understood. Failure to understand and to
comply with the warnings and instructions can result in serious injury,
damage or even death.
Particular attention should be paid to the Warnings, Precautions and
Technical Specifications.
Please keep these instructions for future reference. Updated
instructions and product information are available at:
www.martindale-electric.co.uk
1.1 Meaning of Symbols and Markings
Caution - risk of danger and refer to instructions
Caution - risk of electric shock
Alternating current (AC)
Direct current (DC)
Equipment complies with relevant EU Directives
End of life disposal of this equipment should be in
accordance with relevant EU Directives.
Specification
DT85
Digital thermometer
All specified accuracies are at 23°C ± 5°C, <75% R.H. for 1 year.
Temperature coefficient: 0.1 x (specified accuracy) per °C, (0°C to 18°C, 28°C
to 50°C).
TEMPERATURE
Thermocouple type: K
Temperature scale: Celsius or Fahrenheit, selectable
Measurement ranges: -200°C to 1372°C
-328°F to 2501°F
Resolution: 0.1°C (-100°C to 1372°C)
1°C (-200°C to -100°C)
0.1°F (-100°F to 2000°F)
1°F (-100°F to 2000°F), (2000°F to 2501°F)
Accuracy (to ITS90):
-200°C to -60°C ± (0.1% of rdg + 2°C)
-60°C to 1372°C ± (0.1% of rdg + 1°C)
-328°F to 76°F ± (0.1% of rdg + 4°F)
-76°F to 2501°F ± (0.1% of rdg + 2°F)
Note: thermocouple error is not included in the above accuracy.
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2 11
1.2 Precautions
This product has been designed with your safety in mind, but please
pay attention to the following warnings and cautions before use.
Warnings
In order to avoid the danger of electrical shock, it is important that
proper safety measures are taken when working with voltages
exceeding 30V AC rms, 42V AC peak or 60V DC.
The Martindale DT85 must only be used by a skilled and competent
person who is familiar with the relevant regulations, the safety risks
involved and the consequent normal safe working practices, and
under the conditions and for the purposes for which it has been
constructed and specified.
Before use check the unit for cracks or any other damage. Make
sure the unit is free from dust, grease and moisture. Also check
any associated probes and accessories for damage. Do not use if
damaged.
To avoid electric shock, and damage to the instrument, do not use
this instrument and the associated temperature probe when voltages
at the measurement surface exceed 24V DC or AC rms.
Cautions
To avoid burns or damage to equipment, do not take temperature
measurements inside microwave ovens.
Avoid severe mechanical shock or vibration and extreme temperature.
To avoid possible corrosion from leaking batteries, remove the
batteries if discharged, or when the unit is not in use for an extended
period.
5. WARRANTY AND LIMITATION OF LIABILITY
This Martindale product is warranted to be free from defects in
material and workmanship under normal use and service. The
warranty period is 2 years and begins on the date of receipt by the
end user. This warranty extends only to the original buyer or end-
user customer, and does not apply to fuses, disposable batteries,
test leads or to any product which, in Martindale’s opinion, has been
misused, altered, neglected, contaminated, or damaged by accident
or abnormal conditions of operation, handling or storage.
Martindale authorised resellers shall extend this warranty on new and
unused products to end-user customers only but have no authority to
extend a greater or different warranty on behalf of Martindale.
Martindale’s warranty obligation is limited, at Martindale’s option, to
refund of the purchase price, free of charge repair, or replacement of
a defective product which is returned to Martindale within the warranty
period.
This warranty is the buyer’s sole and exclusive remedy and is in lieu
of all other warranties, expressed or implied, including but not limited
to any implied warranty of merchantability or fitness for a particular
purpose. Martindale shall not be liable for any special, indirect,
incidental or consequential damages or losses, including loss of data,
arising from any cause or theory.
Since some jurisdictions do not allow limitation of the term of
an implied warranty, or exclusion or limitation of incidental or
consequential damages, the limitations and exclusions of this warranty
may not apply to every buyer. If any part of any provision of this
warranty is held invalid or unenforceable by a court or other decision-
maker of competent jurisdiction, such holding will not affect the validity
or enforceability of any other provision or other part of that provision.
Nothing in this statement reduces your statutory rights.
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3
2. INTRODUCTION
2.1 Inspection
Examine the shipping carton for any sign of damage. Inspect the unit
and any accessories for damage. If there is any damage then consult
your distributor immediately.
2.2 Description
The Martindale DT85 has the following functions and features:
Temperature measurement from -200°C to 1372°C or -328°F to
2501°F using K type thermocouple
Selectable temperature scale, Celsius or Fahrenheit
Dual input
Relative, Hold, Max, Min, Max-Min and Average functions
Thermocouple offset adjustment
Auto power off
Low battery indication
LCD display with backlight
Pocket-sized, compact body
2.3 Accessories
The DT85 comes with the following accessories:
2 x K-Type thermocouples
2 x 1.5V AAA batteries
Protective cover for safe storage
Detachable carry strap
Instructions
2.4 Battery Installation
Refer to Section 4.1 (Battery Replacement) for the battery installation
instructions for the DT85.
10
4.4 Repair & Service
There are no user serviceable parts in this unit other than those that
may be described in section 4. Return to Martindale Electric if faulty.
Our service department will provide a quotation to repair any fault
that occurs outside the guarantee period.
Before the unit is returned, please ensure that you have checked the
unit, batteries, thermocouples and poor connections.
4.5 Storage Conditions
The instrument should be kept in warm dry conditions away from
direct sources of heat or sunlight, and in such a manner as to
preserve the working life of the unit. It is strongly advised that the
unit is not kept in a tool box where other tools may damage it.
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4
3. OPERATION
3.1 Low Battery Indication
If the is displayed, the battery needs replacing as measurement
accuracy can no longer be guaranteed (see section 4.1 Battery
Replacement).
3.2 Description of Press Buttons
Selects Set mode settings
Selects/deselects relative function
Turns on/off the DT85, turns on backlight
MODE Selects Set mode and Hold mode functions
3.3 Description of LCD symbols
APO Auto power off is active
Indicates low batteries
HOLD Hold mode is active
MAX Maximum recorded reading is displayed
MIN Minimum recorded reading is displayed
MAX-MIN The difference between maximum and minimum
recorded readings is displayed
AVG The average of recorded readings is displayed
T1 T1 input measured value
T2 T2 input measured value
9
4. MAINTENANCE
4.1 Battery Replacement
The battery compartment is on the rear of the unit.
Push the battery cover up towards the thermocouple inputs and lift
away from the back of the unit.
Replace with 2 new AAA batteries (IEC LR03, NEDA 24A), observing
correct polarity.
Replace the battery cover.
Note: Do not mix old and new batteries.
4.2 Calibration
To maintain the integrity of measurements made using your
instrument, Martindale Electric recommends that it is returned at least
once a year to an approved Calibration Laboratory for recalibration
and certification.
Martindale Electric is pleased to offer you this service. Please contact
our Service Department for details.
Email: [e-mail]
Tel: [phone]
4.3 Cleaning
If contamination is found, clean with a damp soft cloth and if
necessary a mild detergent. Do not use abrasives, abrasive solvents,
or detergents which can cause damage to the unit. If a mild detergent
is used, the unit should subsequently be thoroughly cleaned with a
water dampened soft cloth. After cleaning, dry and allow to remain in
a dry environment for 2 hours before use.
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8 5
T1-T2 Difference between T1 and T2 input measured
values
°C °F Selected temperature scale
Indicates press of button required
REL Relative function is active
ENTER Indicates press of MODE button required
3.4 Power On/Off
To power on in Measurement mode, press for less than 1
second.
To power on in Set mode, press for 2 seconds.
To power off the unit, press for 2 seconds.
3.5 Auto Power Off (APO)
If the unit is inactive for a period of 10 minutes it will automatically
power off.
To disable this function refer to section 3.7.
3.6 Backlight
Press for less than 1 second to turn on the backlight.
It will automatically turn off after 15 seconds if there is no further
operation of the unit.
3.7 Set Mode
This mode sets the following in the order shown:
Auto power off (APO);
Temperature scale;
Thermocouple input 1 offset temperature;
Thermocouple input 2 offset temperature.
Press to select the relative mode and set the current
measurement to zero. The LCD will display REL.
To store a new reference, press as required.
To exit the relative mode, press for 2 seconds.
3.10 Hold Mode
The DT85 has the facility to display the maximum reading, the
minimum reading, the difference between maximum and minimum
readings and the average of the recorded readings.
To enter the Hold mode press MODE while in Measurement mode.
The LCD will display HOLD and the last measured value will be
held on the display.
Successive presses of the MODE button will display the following in
sequence:
HOLD MAX - maximum recorded reading;
HOLD MIN - minimum recorded reading;
HOLD MAX-MIN - difference between max and min recorded
readings;
HOLD AVG - average of the recorded readings.
The unit will return to the Measurement mode at the end of the
above sequence.
To clear the recorded readings, press MODE for 2 seconds
at any point in the above sequence. The unit will return to the
Measurement mode.
Note: The Hold mode will not function until at least 3 measurements
have been stored to memory.
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76
The Set mode is selected by pressing for 2 seconds with the
unit powered off.
If the unit is switched off while in the Set mode, any changed
settings will not be saved, and the unit will revert to the previous
settings.
APO
The LCD will display SEt APO after entering the Set mode.
Press to select ON or OFF as required.
Press MODE to advance to the next function.
Temperature Scale
The LCD will display SEt Unit.
Press to select °C or °F as required.
Press MODE to advance to the next function.
T1 Offset
The LCD will display SEt OFSt and T1 and the right numerical digit
will flash.
Press to increment the digit from 0 to 9 as required. After 9 the
digit will step back to 0.
Press MODE to advance to the left numerical digit that will now flash.
Press to increment the digit from 0 to 9 as required.
If an offset has been entered, pressing the MODE button will allow
the selection of the offset polarity.
Press to select _ (positive offset) or – (negative offset) as
required.
Press MODE to advance to the next function.
T2 Offset
The LCD will display SEt OFSt and T2 and the right numerical digit
will flash.
Set the T2 offset in the same manner as the T1 offset.
Press MODE to save settings and return to the Measurement mode.
3.8 Measurement Mode
If the thermocouples are not fitted, are open circuit or the
measurement limits of the unit have been exceeded OL will be
displayed for the respective thermocouple input.
The maximum temperature measurement of the DT85 is 1372°C
(2501°F), but the thermocouple probe being used may be specified
to a lower temperature. Be sure that the thermocouple probe is
adequate for the measurement being made.
Connect type K thermocouple probes, suitable for the type of
temperature measurement and temperature range being made, to the
thermocouple input sockets T1 and T2.
Taking all necessary safety precautions, position the thermocouple at
the surface or in the medium to be measured.
Read the measured temperatures T1, T2 or T1-T2 from the display.
While in Measurement mode, all measured values are recorded at a
rate of once per second for use by the Hold mode (see section 3.10).
Note: Repeated flexing can break the thermocouple leads. To prolong
lead life, avoid sharp bends in the leads, especially near the
connector.
3.9 Relative Mode
Relative mode allows the current measurements to be zeroed and
stored as reference values.
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