OTC 3990 Hybrid Insulation Multimeter, 1000V CAT III, True RMS, Auto Ranging

OTC 3990 Hybrid Insulation Multimeter, 1000V CAT III, True RMS, Auto Ranging

• OTC 3990 is a hybrid insulation multimeter for diagnosing insulation leakage on hybrid and electric vehicles. It combines insulation resistance testing with full multimeter functions, including True RMS and auto ranging, to deliver accurate results in professional service environments.
• Features:
  • Insulation resistance testing with selectable test voltages enables detection of leakage paths on hybrid and EV systems for safer, faster troubleshooting.
  • True RMS and auto ranging provide accurate readings on complex waveforms while simplifying setup for technicians.
  • Comprehensive DMM functions include diode test, continuity buzzer, data hold, min max, backlight, sleep mode, and low battery display for efficient workflow.
  • 1000V CAT III safety category supports shop practices for vehicle electrical diagnostics on high voltage systems.
  • Supplied kit components allow immediate use without purchasing extra leads or adapters.
• Includes:
  • Heavy duty CAT III test leads with alligator clips
  • Short lead
  • K type temperature adapter
  • User manual
• Specifications:
  • Manufacturer: Bosch OTC
  • Part Number: 3990
  • Product Type / Function: Hybrid insulation multimeter with full DMM functions
  • Insulation Test Voltages: 50V, 100V, 250V, 500V, 1000V
  • AC Voltage Ranges: 6V, 60V, 600V, 1000V
  • DC Voltage Ranges: 6V, 60V, 600V, 1000V
  • Safety Category: 1000V CAT III
  • Alternate Part Numbers / Cross References: OTC 3990; OT3990
  • System Compatibility or Application: Insulation and electrical testing on hybrid and electric vehicle systems
  • Color: Black
• The hybrid insulation multimeter can also be referred to as automotive insulation multimeter, hybrid vehicle multimeter, 1000V CAT III multimeter, True RMS insulation tester, and Bosch 3990 multimeter.

Bosch provides professional diagnostic equipment, electrical test instruments, and service solutions for automotive, commercial, and industrial technicians worldwide.

Q: What distinguishes the 3990 from a standard multimeter?
A: It adds selectable insulation resistance test voltages up to 1000V for locating insulation leakage on hybrid and EV systems, alongside full True RMS multimeter functions.

Q: What comes in the box?
A: Heavy duty CAT III test leads with alligator clips, a short lead, a K type temperature adapter, and the user manual.

Q: Is it suitable for high voltage vehicle diagnostics?
A: Yes. It carries a 1000V CAT III safety rating and is designed for hybrid and electric vehicle electrical testing.