The Fluke 1550C performs digital insulation testing up to 5 kV, and makes data collection easy through the Fluke Connect™ wireless app. Remote operation lets you spend as little time as possible in potentially hazardous zones. Real-time trending shows a live graph on your phone, rather than a hard-to-read set of changing values. And you can create reports quickly, using pre-designed templates that you can customize with company logos. It’s the perfect tool for preventive or predictive maintenance programs designed to identify potential equipment failures before they occur. And it comes with a three-year warranty and CAT IV 600 V safety rating.
Other useful features
• Automatic calculation of Dielectric Absorption (DAR) and Polarization Index (PI) with no additional setup
• Guard system eliminates the effect of surface leakage current on high-resistance measurements
• Selectable test voltages in 50 V steps from 250 V to 1000 V, and 100 V steps above 1000 V
• CAT III 1000 V, CAT IV 600 V safety rating
• Warning function alerts the user that line voltage is present and gives the voltage reading up to 600 V AC or DC for increased user safety
• Measurements can be stored in up to 99 memory locations, with each location assigned a unique, user defined, label for easy recall
• Long battery life gives the user over 750 tests between charges
• Large digital/analog LCD for easy viewing
• Capacitance and leakage current measurement
• Ramp function for breakdown testing
• Resistance measurements up to 2 TΩ
• Timer settings up to 99 minutes for timed tests
• 3-year warranty

Key Features
• Quickly configure, start and stop tests remotely, a safe distance away from any operating, energized equipment, using Fluke Connect® and a smart phone
• Real time trending gives you easy-to-see visual cues
• Report creation using Fluke Connect desktop saves time and makes test results easier to understand
• Fluke Connect saves test results to the cloud for analysis and preventive maintenance

• Save time by seeing voltage and current measurements at the same time
• Visual Continuity™ – the screen automatically turns green for continuity, perfect when it’s too loud to hear the beeper
• FieldSense™ technology for ac voltage, current and frequency, all without making electrical contact to live voltage

• Be aware of voltage easily - the tip glows red and a beeper sounds when voltage is detected
• Continuous self-test so you always know it’s working
• Voltage detection range for wide application use - 90 V to 1000 V AC or 200 V to 1000 V AC
• Audible/Silent mode for added convenience

The Fluke 1535 and 1537 2,500 V Insulation Resistance Testers are engineered to simplify frontline troubleshooting whether you’re on the factory floor or working in the field at a solar installation. With user selectable test voltages from 250 V to 2,500 V and resistance measurements up to 500 GΩ these testers allow you to cover more workload with a single tool. Equipped with an intuitive user interface, a short circuit current of up to 5 mA and a CAT IV 600 V rating these portable high-voltage insulation testers can deliver rapid and stable resistance measurements no matter where you take them. The 1537 Insulation Resistance Tester also allows you to store measurements for later review or PC transfer, using the provided software.
• Selectable Voltage Tests: Tailor your tests with user-selectable voltages of 250 V, 500 V, 1000 V, and 2500 V to cover both industrial and solar applications.
• Extended Insulation Resistance Measurement: Reach up to 500 GΩ in insulation resistance measurement for a thorough analysis.
• Intelligent Calculations: Automatically calculate Polarization Index (PI) and Dielectric Absorption Ratio (DAR), minimizing the influence of environmental factors.
• High Measurement Capacity: Execute up to 1,300 measurements at 2,500 V or 6,500 measurements at 250 V on a single charge, enhancing productivity.
• Enhanced Safety Features: Benefit from a CAT IV 600V rating and a built-in voltage alarm function for heightened safety during operations.
The Fluke 1537 has these additional features:
• Extended Measurements: The Fluke 1537 enhances your testing capabilities with AC/DC voltage and resistance measurements.
• Stable Resistance Measurements: Achieve faster, more stable insulation resistance measurements with a short circuit current up to 5mA.
• Fine-tunable Test Voltage: Adjust the test voltage from 250 V to 2500 V in 100 V increments to meet specific testing requirements.
• Dielectric Discharge Rate Calculation: Automatically calculate the dielectric discharge rate (DD) to aid in identifying elusive insulation issues.
• Ramp Test Mode: Linearly increase the applied test voltage 100 V/s to help identify potentially hard to identify fault conditions.
• Visual and Audio Continuity Indicator: Verify continuity visually on the screen display or with the audible indicator so you can focus on your testing procedure without looking at the display.
• Customizable Testing Parameters: Set user-defined labels, adjust test duration, and store measurement results for a tailored testing experience.
• Effortless Data Management: Download and manage data effortlessly with the provided PC software.
• Extended Warranty: Enjoy peace of mind with an extended 3-year warranty.

Key Features
• User-selectable voltages of 250 V-2500 V
• Up to 500 GΩ insulation resistance measurement
• Short circuit current up to 5mA for fast, stable measurements
• Automatically calculate PI and DAR
• Perform 1,300+ insulation tests on a single charge