HIOKI Insulation Testers for Maintenance
Reliable insulation testing for motors, cables, PV systems, and electrical installations
Insulation testers are used wherever insulation resistance must be checked quickly, safely, and with the appropriate test voltage: in electrical installations, equipment testing, maintenance, troubleshooting, periodic inspections, and commissioning.
Choose the right HIOKI insulation tester from our two main product families:
- High-voltage insulation testers up to 5 kV – for high-voltage testing on cables, transformers, motors, and PV systems, including PV insulation testing during power generation (IR5051, IR5051-90)
- Digital insulation testers up to 1000 V – for electrical installations, equipment testing, motors, control cabinets, and quick field checks
Developed and Made in Japan, HIOKI insulation testers offer the right test voltage range, safety category, and functions for professional field use.
3490 - Analog Insulation Tester, 250 V to 1000 V, up to 4000 MOhm
HIOKI IR4057-90 Digital Insulation Tester with Bar Graph and Bluetooth, 50 V to 1000 V
HIOKI IR5051 - Portable high voltage insulation tester with PV function
IR4053 - Digital Insulation Tester with PVΩ Function, 50 V to 1000 V
IR4017 - Analog Insulation Tester
IR5050 - Portable 5 kV high voltage insulation tester
HIOKI IR4059 - Digital Insulation Tester with Bar Graph and Remote Switch, 50 V to 1000 V
IR4057-50 - Digital Insulation Tester with Bar Graph, 50 V to 1000 V
IR5051-90 - Portable high voltage PV insulation tester with Z3210
HIOKI IR4056 - Digital Portable Insulation Tester, 50 V to 1000 V, up to 4000 MΩ
High Voltage Insulation Testers up to 5 kV
HIOKI high voltage insulation testers are designed for insulation measurements on cables, transformers, motors, and PV systems requiring test voltages above the 1000 V range of standard insulation testers. With selectable test voltages from 250 V to 5 kV and insulation resistance measurement up to 10 TΩ, they support high voltage insulation testing and advanced diagnostics.
In this product group, IR5051 and IR5051-90 include a dedicated PV measurement function for insulation resistance testing on PV systems during power generation, enabling daytime testing without waiting until nightfall. The IR5051-90 includes the Z3210 Bluetooth adapter, while the IR5050 and IR5051 can be expanded with Bluetooth optionally.
| IR5050 | IR5051 | IR5051-90 | |
|---|---|---|---|
| Common features |
|
||
| PV function | N/A | Physically separate PV test section, PV testing up to 2000 V, up to 100 GΩ, during power generation | |
| Bluetooth | Optional with Z3210 Bluetooth adapter | Included | |
Digital insulation testers up to 1000 V
HIOKI digital insulation testers in this group are designed for electrical installations, motors, control cabinets, machinery, and routine insulation testing in maintenance and service. They are the right choice when a dedicated insulation tester is needed for fast, straightforward work in the field. Depending on the model, they provide test voltages from 50 V to 1000 V, insulation resistance measurement up to 4000 MΩ, protective conductor testing, PASS/FAIL evaluation, and voltage verification before insulation testing.
In this product group, the IR4053 adds PVΩ testing on live PV strings, while IR4057-50, IR4057-90, and IR4059 include a digital bar graph. Bluetooth is optional on selected models and included with the IR4057-90. Depending on the model, you can us include a remote switch test lead, integrated hard case, or compact protected housing for daily field use.
Last Call for HIOKI’s Analog Insulation Testers
Digital insulation testers may be the standard today, but analog needle displays still offer a clear advantage in certain insulation measurements. Read why HIOKI’s last analog models remain relevant for specific applications — and why this is the final chance to order them.