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Fluke BT521 Advanced Battery Analyser

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£4,798.80 £3,999.00
Lead Time: 2-3 Weeks Free UK Delivery* Delivery Options

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UK - Highlands & Islands

Includes Northern Ireland (excludes Gibraltar).

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Fluke's most advanced BT500 series battery analyser, the BT521 performs more testing procedures, includes more accessories and is the most comprehensive solution for testing batteries of any type.

Designed with portability in mind and shaped like most common digital multimeters, the BT521 makes battery testing simple. It even includes integrated user-help systems which will guide you through every aspect of configuring a test and audio/visual feedback cues when using the tester's comparison function.

The BT521 comes supplied as standard with Fluke's intelligent test probe. This uniquely designed, long-reach probe includes its own LCD screen for easy viewing of measurement results, can test battery temperature using infrared non-contact technology and also performs voltage, resistance and temperature testing automatically.

Once you're done testing the BT521 stores all of the information directly on the tester in its 999 record internal memory. You can then connect it directly to PC via the USB port/USB cable to download testing information into Fluke's included software package to create reports, quickly compare trends and much more.

This is also the only tester in the range that can be used to measure AC/DC current using the included clamp.

Fluke BT521 Battery Analyser Key Features

  • Suitable for use in testing stationary batteries and battery backup systems of all types
  • Tests resistance, battery voltage (AC/DC), ripple voltage and frequency
  • Comprehensive logging - the BT510 automatically captures data and stores it in its memory
  • Optimised user interface with guided setup and audio/visual feedback cues
  • Use the included battery logging software to analyse results and create reports
  • Powered by rechargeable batteries
  • USB port for download to PC
  • CAT III 600V rated
  • Sequence measurement mode using the included intelligent test probe
  • Threshold comparison - configure multiple reference values and thresholds for resistance and voltage

What's Included?

  • Fluke BT520 Battery Analyser
  • 4-Wire Test Pin (Set)
  • BTL10 Basic Test lead (Set)
  • TL175 TwistGuard Test Leads with Adapter
  • 2x L300 Attachable LED Torches
  • BTL21 Intelligent Test Probe Set with Extender and Temperature Sensor
  • i410 AC/DC Current Clamp
  • Lithium Ion Battery
  • AC Charger
  • Mini USB Cable
  • Shoulder Strap
  • Belt Strap
  • Magnetic Hanging Strap
  • FlukeView Battery Management Software
  • Soft Carrying Case
  • 2 x Spare Fuses
  • 100 x Paper Battery Tags

Fluke BT500 Series Technical Specifications

Functions Range Resolution Accuracy BT510 BT520 BT521
Battery resistance1 3 mΩ 0.001 mΩ 1% + 8
30 mΩ 0.01 mΩ 0.8% + 6
300 mΩ 0.1 mΩ 0.8% + 6
3000 mΩ 1 mΩ 0.8% + 6
Vdc 6 V 0.001 v 0.09% + 5
60 V 0.01 v 0.09% + 5
600 V 0.1 v 0.09% + 5
1000 v 1V 0.09% + 5    
Vac (45 Hz to 500 Hz with 800 Hz filter) 600 v 0.1 v 2% + 10
Frequency (displayed with Vac and Aac)2 500 Hz 0.1 Hz 0.5% + 8
AC voltage ripple (20KHz Max) 600 mV 0.1 mV 3% + 20
6000 mV 1 mV 3% + 10
Adc/Aac (with accessory Fluke i410) 400 A 1 A 3.5% + 2    
Temperature 0°C to 60°C 1°C 2°C (4 °F)    
Meter mode 999 records for each measurement position with time stamp
Sequence mode Up 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 Modes BT510 BT520 BT521
Resistance (mΩ)
Battery voltage
Voltage dc
Voltage ac and frequency (Hz)
Ripple volt
Temperature of negative battery post    
DC and ac current (and frequency)    
DMM mode
Sequence mode
Discharge measurement mode
Automatic measurement save
Wireless commumcation    
Memory view


General Specifications
Size (HxWxD) 22 cm x 10.3 cm x 5.8 cm (9 in x 4 in x 2 in)
Weight 850 g (1.9 lb)
Screen dimensions 7.7 cm x 5.6 cm (3 in x 2.2 in)
Interface USB mini


Environment Specifications
Operating temperature 0°C to 40°C
Storage temperature -20°C to 50°C
Lithium-ion battery charging temperature 0°C to 40°C
Operating humidity Non-condensing (10°C)
<=80% RH (at 10°C to 30°C)
<=75% RH (at 30°C to 40°C)
Operating altitude Sea level to 2000 meters
Storage altitude Sea level to 12,000 meters
IP rating IP40
Radio FCC Class A
Vibration requirements MIL-PRF-28800F: Class 2
Drop test requirements 1 meter
Temperature coefficients Add 0.1 x specified accuracy for each degree C above 28°C or below 18°C
Safety compliance 600 V CAT III
EMC IEC 61326
ROHS China, Europe
Protection class 2 Pollution Degree II
Battery compliance UN38.3
2G per IEC68-2-26, 25G, and 29
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Additional Information
Manufacturer Part Code 4489996
Country of Origin China

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