Digi-Sense 20250-92 User manual

User Manual
THE STANDARD IN PRECISION MEASUREMENT
Dual-Input Data Logging
Thermometers
with NIST-Traceable Calibration
Thermocouple Meter,
Type J/K/T Input
Model 20250-92
Thermistor Meter
Model 20250-94
RTD Meter
Model 20250-96
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Introduction
The Digi-Sense Dual-Input Thermometers with Data
Logging (20250-92, -94, -96) offer fast response and
high accuracy. Advanced features include data logging,
USB interface, relative time clock, offset compensation,
temperature differential, data Hold, Max/Min/Avg readings,
and auto power-off. The instrument is fully tested and
calibrated to NIST-traceable standards. Careful use of this
meter will provide years of reliable service.
Unpacking
Carefully unpack the instrument and accessories from
shipping package. Check individual parts against the list
of items below. If anything is missing or damaged, please
contact your instrument supplier immediately.
1. Meter
2. USB cable
3. Software
4. Soft carrying case
5. Lanyard
6. One 9 volt battery
7. User manual
8. NIST-traceable calibration report with data
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Key Features
• Large backlit display shows any combination of
T1, T2, T1–T2; plus Max, Min, and Avg readings
• Relative time clock on Max/Min/Avg provides a
time reference for major events
• Electronic Offset function allows compensation of
probe errors to maximize overall accuracy
• USB interface
• Data logging capacity of 16,000 sampling points
• User-selectable readout in °C or °F
• Automatic power-off (sleep) mode conserves battery life
• Dual sensor inputs; accept a wide variety of probes
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Meter Description
1. Up () button
2. Down () button
3. MODE (Max/Min/Avg/Dif)
button
4. SET button
5. Backlight button
6. LOG (data logging) button
7. Data HOLD button
8. CAL (offset/calibration)
button
9. Power on/off button
10. LCD
11. Temperature sensor
inputs (2)
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Display Layout
1. Hold icon
2. Low-battery indicator
3. MAX icon
4. MIN icon
5. AVG icon
6. DIF icon
7. User-selectable tempera-
ture units (°C or °F)
8. Low alarm icon
9. High alarm icon
10. Real-time clock
11. Data logging icon
12. T2 temperature value
13. T2 input icon
14. T2 input type (J, K, T;
20250-92 only)
15. T1 temperature value
16. T1 input icon
17. T1 input type (J, K, T;
20250-92 only)
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Setup and Operation
Measuring Temperatures
1. Plug the probe(s) into the T1 or T2 input connector(s).
Make sure that the polarity is correct.
2. Press power on/off button to turn on the thermome-
ter. After one second the thermometer displays the
first reading. The screen will display the current
measured value and the maximum temperature.
3. If no probe is plugged into the selected input or the
probe is not connected properly, the display shows
"- - - -". If the temperature being measured is outside
the meter’s valid range, the display shows
“OL” (overload).
Thermocouple Input Function (20250-92 only)
1. Press SET button to enter setup mode.
2. Toggle through the setup options until the T1 or T2
input icon starts to flash.
3. Use the Up () and Down () buttons to select the
desired thermocouple input type J, K, or T.
4. Press the SET button again to exit.
Backlight Function
1. The backlight is automatically set to come on for
30 seconds when the meter is powered on.
2. Press Backlight button to turn on for 5 minutes
without activity.
3. Press Backlight button again to turn off the backlight
prior to the 5 minutes elapsing.
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Temperature Units Function
1. Press SET button to enter setup mode.
2. Toggle through the setup options until the
temperature unit of measure icon starts to flash.
3. Use the Up () and Down () buttons to select the
desired the temperature unit of measure °C/°F.
4. Press the SET button again to save setting and
exit mode.
Hold Function
1. Press the HOLD button to freeze the readings on the
display. The display shows the HOLD icon.
2. Press the HOLD button again to turn off the
Hold function.
3. The Hold function does not freeze the Max or Min
function or stop the meter from updating.
Max/Min Function
1. Press MODE button to enter the mode function.
2. Toggle through the mode options by pressing the
MODE button to select the MAX or MIN icon on the
display.
3. The T1 and T2 temperature values will display the
maximum (Max) or minimum (Min) readings.
4. To exit, toggle through the Mode options until the
mode types disappears.
5. Simultaneously press the Up () and Down ()
buttons to recalculate the stored maximum and
minimum values in the meter.
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Average (AVG) Function
1. Two probes must be inserted into channels T1 and
T2 for this function to work.
2. Press the MODE button to enter the mode function.
3. Toggle through the mode options by pressing the
MODE button to select the AVG icon on the display.
4. The T1 temperature value will display real-time
readings.
5. The T2 temperature value will display the real-time
average temperature between channels T1 and T2.
6. To exit, toggle through the Mode options until the
mode types disappears.
Differential (DIF) Function
1. Two probes must be inserted into channels T1 and
T2 for this function to work.
2. Press the MODE button to enter the mode function.
3. Toggle through the mode options by pressing the
MODE button to select the DIF icon on the display.
4. The T1 temperature value will display real-time
readings.
5. The T2 temperature value will display the real-time
differential temperature between channels T1 and
T2.
6. To exit, toggle through the Mode options until the
mode types disappears.
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Offset/Calibration Function
Using the Offset to Adjust for Probe Errors
Use the offset/calibration option to adjust the meter’s
readings to compensate for the errors of a specific
sensor. The allowable adjustment range is ±9.0°F or
±5.0°C.
1. Plug the probe into the meter’s input connector.
2. Place the probe in a known, stable temperature
environment (such as an ice bath).
3. Allow the readings to stabilize.
4. Adjust the offset until the primary reading matches
the calibration temperature.
Adjusting the Offset
The primary display shows the temperature plus the
offset and the secondary display shows the offset.
1. Press the CAL button for 3 seconds to enter user
calibration T1 mode (alarm will sound).
2. Press the Up () or Down () buttons to adjust the
offset by 0.1°. The max offset value is 5°.
3. Press the CAL button again for 3 seconds to enter
user calibration T2 mode (alarm will sound).
4. Press the Up () or Down () buttons to adjust the
offset by 0.1°. The max offset value is 5°.
5. Pressing the CAL button a third time will save the
settings and return to normal measurement mode.
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Alarm Function
1. The high and low alarm limits are set in the
software only.
2. The meter must be connected to your PC via
a USB cable.
3. Click on the Setup icon in the software to adjust the
alarm limits for both T1 and T2 channels.
4. By clicking OK in the software setup window, the
alarm limits are saved and downloaded to the meter.
5. To deactivate the alarm sound on the meter, press the
HOLD button for one second, then press Up () button.
6. To reactivate the alarm sound on the meter, press the
HOLD button for one second, then press Up () button.
7. The display will show a “Bell On” or “Bell Off” icon.
Data Logging Functions
Setting Sampling Rate
1. Press SET button to enter setup mode.
2. Toggle through the setup options until the LOG icon
starts to flash.
3. The clock function will change to show the current
data logging sampling rate.
4. To adjust the sampling rate, use the Up () and
Down () buttons.
5. Sampling rate can be adjusted from 1 second to
60 minutes.
6. Press the SET button again to save setting and
exit mode.
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Data Logging
1. Press LOG button to start recording data based
on the sampling rate set.
2. Pressing the LOG button a second time for 2 seconds
will end the recording function.
3. The sampling rate cannot be changed during data
recording.
4. When the sampling rate is set to 0 second or the mem-
ory is full, pressing the LOG button will not start the
recording function. The LOG icon will flash on the dis-
play for half a second and then disappear.
5. If data is being recorded over 15 minutes without any
other operation, the meter will enter sleep mode. Sleep
mode does not affect the recording of data.
Clearing Memory
1. Press the HOLD button for 1 second, then press the
Down () button to delete all stored data.
2. The display will show “d dAtA CLR”, and then return to
normal measurement mode.
3. If the user presses the HOLD button for more than
4 seconds and then presses the Down () button,
the memory will not be cleared.
Auto Power-Off (APO) Mode
1. The meter’s default mode is to automatically shut off
after 15 minutes of non-use.
2. If data is being recorded over 15 minutes without any
other operation, the meter will enter sleep mode. Sleep
mode does not affect the recording of data.
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Data Logging Functions (continued)
3. When data is being recorded, the recorded data is
automatically saved before the shutdown.
Note: The USB port serves as an external power supply and for data
transferring.
Recording/Data Logging Operation (Software)
1. First install software on PC following the setup
wizard (see the following “Software Installation”
section). Once software is successfully installed, the
software icon shortcut will be automatically placed
on your PC desktop.
2. Connect the meter to your PC via the supplied USB
cable.
3. Power the meter on.
4. Open the installed Data Logger Software by
double-clicking on the icon on your PC desktop.
5. On the menu bar, select the green download arrow
to download the recorded data from the meter to
the software.
6. In the Data Logger Setting menu, confirm the
sampling rate, unit of measure, probe type
(20250-92 only), and alarm limits, then select “OK”.
7. See the Help icon within the software for detailed
instructions on other software functions.
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Software Installation
1. Insert the CD into the PC.
2. Double-click the set up.exe file to launch the
software installation program.
3. Follow the installation wizard to complete the
installation.
4. If the USB driver needs to be updated or driver error
message is received, please go to the folder with driver
on the CD to update the driver.
5. Upon successful installation of the software, the software
icon shortcut will be automatically placed on your PC
desktop.
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Specifications
Sampling rate: Three times every two seconds (default rate)
Auto power-off: Unit shuts off automatically after 15 minutes
to preserve battery life
Operating temperature: 32 to 122°F (0 to 50°C)
Storage temperature: 14 to 122°F (–10 to 50°C)
Weight: 6.2 oz (177 g)
Dimensions: 7" x 21⁄4" x 1" (17.8 x 5.7 x 2.6 cm)
Power: One 9 volt battery
Range Resolution Accuracy
Thermocouple meter 20250-92
Type J: –328 to 1832°F
(–200 to 1000°C)
0.1°F (0.1°C) from –148 to
1832°F (–99.9 to 999.9°C);
1°F (1°C) outside range
±1 of reading + 1.8°F (1°C)
below –148°F (–99.9°C);
±1 of reading + 0.9°F (0.5°C)
above –148°F (–99.9°C)
Type K: –418 to 2501°F
(–250 to 1372°C)
Type T: –418 to 752°F
(–250 to 400°C)
Thermistor meter 20250-94
–40 to 257°F
(–40 to 125°C) 0.1°F (0.1°C)
±0.9°F (±0.5°C) from 32 to
158°F (0 to 70°C); ±2°F (1°C)
outside range
RTD meter 20250-96
–320 to 1562°F
(–200 to 850°C)
0.1°F (0.1°C) from –148 to
1562°F (–99.9 to 850°C);
1°F (1°C) outside range
±1.5°F (0.8°C) from –148
to 392°F (–99.9 to 199.9°C);
±2°F (1°C) + 0.5% of reading
outside range
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Maintenance, Recalibration, and Repair
Cleaning and Storage
• The meter should be cleaned with a damp cloth and
mild detergent when necessary. Do not use solvents
or abrasives.
• Store the meter in an area with moderate temperature
and humidity (refer to the operating and storage ranges
in the specifications chart earlier in this manual).
Battery Replacement
When the battery power falls low, the low-battery icon will
appear on the screen. Replace the one 9 volt battery by
removing the screw holding the rear battery compartment
cover to access the battery compartment. Ensure that the
compartment cover is securely fastened when finished.
Note: If you do not intend to use thermometer for a long time,
remove the batteries.
It is recommended that Digi-Sense products are calibrated
annually to ensure proper function and accurate measure-
ments; however, your quality system or regulatory body
may require more frequent calibrations. To schedule your
recalibration, please contact InnoCal, an ISO 17025 calibra-
tion laboratory accredited by A2LA.
Phone: 1-866-INNOCAL (1-866-466-6225)
Fax: [phone]
E-mail: [email protected]
Web: InnoCalSolutions.com
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For Product and Ordering Information, Contact:
Toll-Free: 1-800-323-4340
Phone: [phone]
Fax: [phone]
ColeParmer.com/Digi-Sense
Toll-Free: 1-800-358-5525
Phone: [phone]
Fax: [phone]
Davis.com/Digi-Sense
1065DGMAN_20250-92,-94,-96 Manual Part No. 00100-22
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