• Pre-set test voltages of 250V, 500V, 1000V and 2500 V to cover both industrial and solar applications
• Insulation resistance measurement from 200kΩ to 500GΩ
• Polarization Index (PI) measurement
• Dielectric Absorption Ratio (DAR) measurement
• PI and DAR are automatically calculated while minimizing the influence of environmental factors

The Fluke 1535 and 1537 2500 V Insulation Resistance Testers are engineered to simplify frontline troubleshooting whether you are on the factory floor or working in the field at a solar installation. With user selectable test voltages from 250 V to 2500 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 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 Fluke 1537 offers several additional features and testing functions not found on the 1535.

Features found on the 1537, but not on the 1535 include:

• 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

The chart below outlines several main differences between them.