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    FLUKE BT521 Advanced Battery Analyzer 24.8 x 11.5 x 9.4 inches

    # BT521

    • Measure the voltage of the battery under test
    • Measures unwanted residual ac component of the rectified voltage in dc charging and inverter circuits.
    • Measures the resistance of the intercell connection between batteries in a string.

    Reduced testing complexity, a simplified workflow and an intuitive user interface provide a new level of ease-of-use in battery testing.


    • The ideal test tool for maintenance, troubleshooting and performance testing of individual stationary batteries and battery banks used in critical battery back-up applications
    • The intuitive user interface, compact design and rugged construction ensure optimum performance, test results and reliability
    • Covers a broad range of battery test functions ranging from DC voltage and resistance tests to full condition testing using automated string function testing and the test probe integrated infra-red temperature measurement system
    • Designed for measurements on stationary batteries of all types.

    Voltage and Resistance Thresholds


    Fluke Battery Analyzers allow you to quickly and easily define upper and lower measurement thresholds or tolerance ranges. During the testing process, measured values are automatically compared to the predefined threshold levels producing a PASS, FAIL or WARN indication after each measurement. A maximum of 10 sets of thresholds can be stored and threshold indications are determined based on the following criterion:

    > Voltage Lower< Voltage Lower< Reference> Reference and Reference x (1+Warning %)> Reference x (1+Fail)

    Fluke Battery Management Software

    Fluke Battery Management Software Easily allows you to quickly and easily import data from the battery analyzer to a PC. The measurement data and battery profile information is stored and archived with the Management Software and can be used compare results, switch results between conductance and resistance readings and perform trend analysis. All measurement data, battery profile and analysis information can be used to easily generate reports.

    • Quick view saved readings
    • Profile management
    • Histogram of a battery string with end user defined threshold
    • Historical trend data of batteries
    • Multiple rounds of discharge voltage
    • Quick Report Generation
    • Upgrade Fluke Battery Analyzer firmware
    • Switch measurement results between conductance and resistance readings

    Fluke Battery Analyze mobile app

    The BT521 offers wireless communication for data download and remote display while measuring via the dedicated Fluke Battery Analyzer mobile app (note: the Fluke BT521 is not currently Fluke Connect compatible). Using the Fluke Battery Analyze mobile app you can:

    • Browse profile
    • Review sequence testing data
    • E-mail sequence testing data

    Fluke BT500 key features:


    • Battery Voltage – During the internal resistance test, Fluke Battery Analyzers also measure the voltage of the battery under test
    • Discharge Volts – The Discharge mode collects the voltage of each battery multiple times at a user defined interval during a discharge or load test. Users can calculate the time a battery takes to drop to the cut-off voltage and use this time to determine the capacity loss of the battery
    • Ripple Voltage Test – Measures unwanted residual ac component of the rectified voltage in dc charging and inverter circuits. Allows users to test ac components in dc charging circuits and find one of the root causes of battery deterioration
    • Meter and Sequence Modes – The Meter mode is used for a quick test or troubleshooting. In this mode you can save and read the readings in a measurement or time sequence. The Sequence mode is for maintenance tasks with multiple power systems and battery strings. Before a task starts, users can configure a profile for the task for data management and report generation
    • Threshold and Warning – Users can configure a maximum of 10 sets of thresholds and receive a Pass/ Warning/ Fail indication after each measurement
    • Intercell Strap Resistance Test and Data Management – Measures the resistance of the intercell connection between batteries in a string.
    • AutoHold – When AutoHold is turned on, a reading is captured when it remains stable for 1 second. The reading is then released when a new measurement starts
    • AutoSave – When AutoSave is turned on, measured values are saved to internal memory automatically after an AutoHold reading is captured
    • Fluke Battery Management Software – Easily import data from the Product to a PC. The measurement data and battery profile information is stored and archived with the Management Software and can be used for comparison and trend analysis. All measurement data, battery profile and analysis information can be used to easily generate reports
    • Comprehensive logging – All measured values are automatically captured during testing and can be reviewed on the instrument before downloading for on the-go analysis
    • Optimized user interface – Quick, guided setup ensures you’re capturing the right data every time
    • Battery life – 7.4 V 3000 mAh lithium-ion battery for more than eight hours continuous operation.
    • USB port – For fast data download to supplied data analysis and report management application software.
    • Highest safety rating in the industry – CAT III 600 V, 1000 V dc max. rated for safe measurements all around the battery power supply equipment.

    Fluke BT521 Key features: (Designed for users who need to incorporate temperature measuring)


    • Wireless capability works with Fluke Battery Analyze mobile app (Fluke BA Mobile)*
      • View profile and associated test results from the Battery Analyzer
      • Send out the profile and test results via Email with (.csv) data format
    Battery Resistance / Strap Resistance13 mΩ0.001 mΩ1% + 8
    1% +68
    30 mΩ0.01 mΩ0.8% + 6
    300 mΩ0.1 mΩ0.8% + 6
    3000 mΩ1 mΩ0.8% + 6
    VDC6 V0.001 V0.09% + 5
    60 V0.01 V0.09% + 5
    600 V0.1 V0.09% + 5
    1000 V1 V0.09% + 5
    VAC (45 Hz to 500 Hz with 800 Hz filter)600 V0.1 V2% + 10
    Frequency (displayed with VAC and AAC)2500 Hz0.1 Hz0.5% + 8
    AC voltage ripple (20 KHz  Max)600 mV0.1 mV3% + 20
    6000 mV1 mV3% + 10
    ADC/AAC (with accessory Fluke i410)400 A1 A3.5% + 2
    Temperature0°C to 60°C1°C2°C (4°F)
    Meter mode999 records for each measurement position with time stamp
    Sequence modeUp to 100 profiles and 100 profile templates (Each profile stores up to 450 batteries) with time stamp
    1. The measurement is based on AC injection method. The injected source signal is < 100 mA, 1 kHz.
    2. Trigger level VAC: 10 mV, AAC: 10 A
    Measurement ModesBT510BT520BT521
    Resistance (mΩ)
    Battery voltage
    Voltage DC
    Voltage AC and frequency  (Hz)
    Ripple volt
    Temperature of negative battery post (using BTL21 straight probes)
    DC and AC current (and frequency)
    DMM mode
    Sequence mode
    Discharge measurement mode
    Automatic measurement  save
    Wireless commumcation
    Memory view
    General Specifications – Battery Analyzer
    Size (H x W x D)22 x 10.3 x 5.8 cm (9 x 4 x 2 in)
    Weight850 g (1.9 lb)
    Screen dimensions7.7 x 5.6 cm (3 x 2.2 in)
    InterfaceUSB mini
    Warranty3 years
    General Specifications – BTL20ANG Angled Measurement Probe
    Long angled probe (overall length)242.2 cm (95.38 in)
    Short angled probe (overall length)216.8 cm (85.38 in)
    Overall span (coil relaxed)10.1 cm (4 in)
    Overall maximum span (coil extended)109.2 cm (43 in)
    BTL20ANG probe tip angle20 degrees from horizontal
    Environment Specifications
    Operating temperature0°C to 40°C
    Storage temperature-20°C to 50°C
    Lithium-ion  battery charging temperature0°C to 40°C
    Operating humidityNon-condensing (10°C)
    ≤ 80% RH (at 10°C to 30°C)
    ≤ 75% RH (at 30°C to 40°C)
    Operating altitudeSea level to 2000 meters
    Storage altitudeSea level to 12,000 meters
    IP ratingIP40
    RadioFCC Class A
    Vibration  requirementsMIL-PRF-28800F: Class 2
    Drop test  requirements1 meter
    Temperature coefficientsAdd 0.1 x specified accuracy for each degree C above 28°C or below 18°C
    Safety  compliance600 V CAT III
    EMCIEC 61326
    ROHSChina, Europe
    Protection class 2Pollution Degree II
    Battery complianceUN38.3
    2 G per IEC68-2-26, 25 G, and 29
    • Battery analyzer
    • 4-wire test pin (set)
    • BTL10 Basic Test Lead (set)
    • TL175 TwistGuardª Test Leads with adapter
    • BTL21 Intelligent Test Probe Set, with extender and temperature sensor
    • i410 AC/DC Current Clamp
    • BP500 lithium-ion battery
    • BC500 AC charger
    • mini-USB cable
    • Shoulder strap
    • Belt strap
    • Magnetic hanging strap
    • FlukeView¨ Battery Management Software
    • Soft carrying case
    • Spare fuses (2)
    • Battery tags
    • Zero Ohm Calibration Resistor

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      *Demonstrations can only be scheduled within the UAE

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