Fluke 1537 Insulation Tester, 250 V Min, 2500 V Max, 500 GΩ CAT IV

This insulation tester is a handheld instrument for assessing electrical insulation integrity in industrial and field environments. It offers selectable test voltages from 250V up to 2500V and is intended for technicians working on machines, installations and renewable-energy systems. The unit features an LCD for clear readouts and runs from AA alkaline cells for portable operation.

• 500GΩ measurement range delivers detection of very high insulation resistance
• 250–2500V selectable test voltages support diverse system requirements
• Short-circuit current up to 5mA enables fast, stable readings
• Automatic PI and DAR calculations reduce environmental measurement influence
• CAT IV 600V rating provides elevated overvoltage protection during testing
• Stores and exports results for workflow traceability and analysis

• Suitable for insulation testing on solar PV arrays and inverters
• Ideal for preventative maintenance on motors and generators
• Used for commissioning high-voltage distribution equipment
• Can be used for fault tracing on electrical switchgear and control panels

With eight AA alkaline cells installed, you can perform over 1,300 insulation tests at the highest test voltage and many more at lower voltages before replacement is required.

The Advanced variant measures AC/DC voltage and resistance ranges to 600V and up to 60kΩ, Plus capacitance and leakage current within specified ranges.

Test voltage accuracy is specified as −0% and +10% at 1mA load current, and charging/discharging rates for capacitive loads are provided to predict test timing.

It meets IEC 61557 insulation measurement standards, IEC 61010 safety requirements, Pollution Degree 2 classification and an IP40 enclosure rating.