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Fluke Calibration 1523 Handheld Thermometer Readout

The 1523 Reference Thermometer from Fluke’s Hart Scientific Division measures, graphs, and records PRTs, thermocouples, and thermistors.

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  • Measure, graph and record three sensor types with one tool

    The 1523 Reference Thermometers from Fluke’s Hart Scientific Division measure, graph, and record PRTs, thermocouples, and thermistors. These thermometer readouts deliver exceptional accuracy, wide measurement range, logging, and trending, all in a handheld tool you can take anywhere.

    The 1523 lets you handle field applications, laboratory measurements, and data logging with ease. With the dual channel measurement capabilities of the model 1524, you can do twice the work in half the time.

    Three sensor types

    • PRTs: –200°C to 1000°C
    • Thermocouples –200°C to 2315°C
    • Precision thermistors: –50°C to 150°C


    • PRTs: up to ±0.011°C
    • Thermocouples: ±0.24°C for J,K,L,M
    • Precision thermistors: ±0.002°C

    Fast mode

    • PRTs: 0.45 seconds per sample
    • Thermocouples: 0.3 second per sample
    • Precision thermistors: 0.3 seconds per sample

    Two models

    • 1523: Single channel standard model; memory for 25 readings and statistics
    • 1524: Two channels; memory for logging 15,000 measurements; real-time clock for time and date stamps

    Graphical display

    • 128x64 backlit LCD graphic display
    • Plot and scale trends in real time
    • Simultaneous dual channel readings
  • Make accurate, consistent measurements… anywhere.

    You need accuracy for compliance, product yields, energy savings, and consistent results. The 1523 uses current reversal, a technique used in high-end instruments that eliminates thermal EMFs, for precision temperature measurements. Specifications are guaranteed from -10°C to 60°C ambient. Special precision resistors and a highly stable reference voltage source keep the 1523 accuracy virtually insensitive to environmental temperature.

    Like all Fluke handheld tools, the 1523 Reference Thermometers endure rigorous testing in temperature extremes and under harsh conditions of vibration, so you can take them anywhere you need to go.

    An optional magnetic hanger allows you to hang the thermometer for easy viewing while freeing your hands to focus on the job.

    INFO-CON connectors ensure correct temperature conversion

    Inside the INFO-CON, a memory chip keeps calibration information for the attached probe. Simply plugging in the probe uploads the information to the readout, ensuring the correct temperature conversion for accurate, hassle-free measurements.

    Probes may be locked by password to specific channels and readouts for security or for system calibration traceability. Plug any thermocouple with mini-thermocouple jacks into an optional universal thermocouple adapter for convenient measurement. Each thermocouple adapter or standard connector supports reference junction compensation (RJC) with its own internal precision thermistor.

    Monitor trends in the lab or in the field

    See trends graphically on the 1523 thermometer’s 128x64-backlit LCD display. You can change the graph’s resolution at the touch of a button. Now it’s easy to see when the temperature is stable, without statistics or long delays, or monitor processes over time to verify correct operation.

    Document on demand up to 25 readings and associated statistics for easy retrieval. You can view the data through the display or by uploading it to a PC via RS-232 connection and 9940 software, included free. To monitor and log more data over time, use a PC and optional LogWare II software.

    RS-232-to-USB adapters are available for those who prefer USB connectors. Battery power lasts at least 20 hours on three AA batteries, or use the dc power adapter for extended periods of measurement. Power saving features can be enabled or disabled for longer battery life or greater convenience.

    Two models let you make the best choice for your application

    The 1523 Reference Thermometer is a versatile single-channel thermometer that measures, graphs and records three sensor types with one tool. Support for PRTs/RTDs, thermocouples, and thermistors provides flexibility to choose the right probe for the job.

    The new 1524 Reference Thermometers help you do twice the work in half the time. Two channels and three sensor types and high-speed measurement make you more productive and make model 1524 the one reference thermometer you need to own. It has all the features of the 1523, and it’s a data logger too. A real-time clock and memory for 15,000 time and date stamped measurements mean everything you are going to need is in this package. Log up to three times per second, or once every hour or other options in between. Download the data to a PC for analysis when you need it.


    Calibration, loop checking, plant startup, troubleshooting, maintenance, and repair are some of the varied duties that need a 1523 thermometer. Use it for a handy temperature reference in baths, dry-block calibrators, thermowells, clean rooms, engines, heat exchangers, furnaces, freezers, or anything else that must be calibrated, checked, or maintained.

  • Specifications
    Input channels 1
    Logging 25 readings with statistics
    Sample interval
    1 second
    Sample interval (fast mode) 0.3 seconds (see technical manual for details)
    Sensor types PRTs, RTDs, Thermistors, and Thermocouples
    Thermocouple types C,E,J,K,L,M,N,T,U,B,R,S
    Operating temperature -10°C to 60°C (Best accuracy 13°C to 33°C)
    Power requirements 3 AA alkaline batteries
    Size 96 x 200 x 47 mm
    (3.75 x 7.9 x 1.86 in)
    Weight 0.65 kg (1.4 lb)
    Environmental conditions for best accuracy 13°C to 33°C
    Millivolt range and accuracy –10 mV to 75 mV ±(0.005% + 5 μV)
    Resistance range and accuracy 0 Ω to 400 Ω ±(0.004% + 0.002 Ω)
    200 Ω to 50 kΩ ±(0.01% + 0.5 Ω)
    50 kΩ to 500 kΩ ±(0.03%)
    Temperature coefficient, voltage (–10°C to 13°C , +33°C to 60°C) ±(0.001%/°C + 1 μV/°C)
    Temperature coefficient, resistance (–10°C to 13°C , +33°C to 60°C) 0.0008%/°C + 0.0004 Ω (0 Ω to 400 Ω)
    0.002%/°C + 0.1 Ω (0 Ω to 50 kΩ)
    0.06%/°C + 0.1 Ω (50 kΩ to 500 kΩ)
    Excitation current, resistance 1 mA (0 Ω to 400 Ω)
    10 μA (0 Ω to 50 kΩ)
    2 µA (50 kΩ to 500 kΩ)
    Thermocouple Equivalent Temperature Accuracies (readout only)
    Type B ±0.85°C from 600°C to 800°C
    ±0.68°C from 800°C to 1000°C
    ±0.57°C from 1000°C to 1800°C
    Type C ±0.32°C from 100ºC to 550°C
    ±0.71°C from 550°C to 2300°C
    Type E ±0.52°C from -200°C to 0°C
    ±0.22°C from 0°C to 950°C
    Type J ±0.52°C from -200°C to 0°C
    ±0.23°C from 0°C to 1200°C
    Type K ±0.61°C from -200°C to 0°C
    ±0.24°C from 0°C to 1370°C
    Type L ±0.36°C from -200°C to 0°C
    ±0.23°C from 0°C to 1370°C
    Type M ±0.26°C from -20°C to 0°C
    ±0.25°C from 0°C to 400°C
    ±0.22°C from 400°C to 1400°C
    Type N ±0.72°C from -200°C to 0°C
    ±0.28°C from 0°C to 1300°C
    Type R ±1.09°C from -20°C to 0°C
    ±0.97°C from 0°C to 500°C
    ±0.49°C from 500°C to 1750°C
    Type S ±1.05°C from -20°C to 0°C
    ±0.95°C from 0°C to 500°C
    ±0.56°C from 500°C to 1750°C
    Type T ±0.60°C from -200°C to 0°C
    ±0.25°C from 0°C to 400°C
    Type U ±0.54°C from -200°C to 0°C
    ±0.24°C from 0°C to 400°C
    Accuracies are based on internal Reference Junction Compensation. Refer to Technical manual for equivalent accuracies with an external reference junction.
    Accuracies with Selected Probes (±°C)
    -200°C 5616-12: 0.014
    5615-6: 0.025
    5627A-12: 0.027
    5610-9: n/a
    0°C 5616-12: 0.021
    5615-6: 0.021
    5627A-12: 0.049
    5610-9: 0.009
    100°C 5616-12: 0.027
    5615-6: 0.028
    5627A-12: 0.065
    5610-9: 0.009
    300°C 5616-12: 0.040
    5615-6: 0.043
    5627A-12: 0.103
    5610-9: n/a
    420°C 5616-12: 0.050
    5615-6: n/a
    5627A-12: 0.130
    5610-9: n/a
    Includes readout accuracy, probe calibration, and probe drift
    PRT Equivalent Temperature Accuracy (readout only)
    –100°C ±0.011
    0°C ±0.015
    100°C ±0.019
    200°C ±0.023
    400°C ±0.031
    600°C ±0.039
    Thermistor Equivalent Temperature Accuracy (readout only)
    0°C ±0.002
    25°C ±0.003
    50°C ±0.006
    75°C ±0.014
    100°C ±0.030
    • Models
      Model Name Description  
      Fluke 1523 Fluke Calibration 1523 Handheld Thermometer Readout
      1 Channel
      Fluke 1523-P1 Fluke Calibration 1523-P1 Handheld Thermometer Readout
      5616 PRT (–200°C to 420°C, 100 ohm (1/4 x 12 inch))


      • Universal TC INFO-CON Connector
      • TPAK
      • Case
      Fluke 1523-P2 Fluke Calibration 1523-P2 Handheld Thermometer Readout
      5628 PRT (–200°C to 660°C, 25 ohm (1/4 x 12 inch))


      • Universal TC INFO-CON Connector
      • TPAK
      • Case
      Fluke 1523-P3 Fluke Calibration 1523-P3 Handheld Thermometer Readout
      5627A PRT (–200°C to 420°C , 100 ohm (12 x 1/4 inch))


      • Universal TC INFO-CON Connector
      • TPAK
      • Case
    • Cases & Holsters
      Model Name Description  
      Fluke TPAK Fluke TPAK ToolPakTM Magnetic Meter Hanger Fluke Store
    • Options
      Model Name Description  
      Fluke 1930 Fluke 1930 System Calibration, PRT with Readout, Accredited
    • Temperature Accessories
      Model Name Description  
      Fluke 80PJ-1 Fluke 80PJ-1 Bead Probe Fluke Store
      Fluke 80PK 1 Fluke 80PK-1 Bead Probe Fluke Store
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