Hioki ST5520 Megohmmeter / Insulation Resistance Testers

• ST5520 Insulation Testers (with External I/O Output)
• Quick discharge of residual voltage
• Freely configurable test voltage (Set from 25 V to 1000 V, 1 V resolution)
• Contact check function (Prevents errors due to poor contact)
• Short-circuit check function (Stops potentional defects from reaching th

The Hioki electrical safety test instrument series is designed for insulation resistance and voltage withstand testing of electrical devices and components according to various safety standards. The ST5520 and ST5520-01 are the fastest insulation testers in the industry, delivering pass/fail assessment in as fast as 50 ms. 25 to 1000 V test voltage with 1 V resolution.

Rapidly assess in as fast as 50 ms
Testing is complete in as little as 50 ms — the fastest time in the industry. This is 700 ms faster than legacy Hioki models.

• Discharge time varies according to the sample's capacitance
• The pictured waveform reflects use of a test time of  45 ms
• The waveform shows the test result for a 9 MΩ, 10 pF sample

Quickly discharge residual voltage
The post-test residual voltage discharge time has been reduced significantly compared with legacy models. As a result, when comparing an identical sample under the following conditions, a takt time improvement of 990 ms is estimated.

• Discharge time varies according to the sample's capacitance
• The waveform shows the test result for a 9 MΩ, 10 pF sample

Prevents errors due to poor contact
The contact check function allows you to check that proper contact has been made with the device under test prior to the testing. This ensures that resistance testing is not carried out without proper contact, as this can result in erroneous assessment. There are two methods: 4-wire contact check and comparator contact check.