Insulation resistance tester KEW3127 250V-5000V, DAR, PI, RAMP 103911

Advanced insulation diagnostics in the field and laboratory

KEW3127 is a high-voltage insulation resistance tester from the Japanese brand Kyoritsu, designed for professional diagnostic and periodic measurements in electrical installations, industrial machinery, and energy infrastructure. The device supports five test voltages - 250 V, 500 V, 1000 V, 2500 V and 5000 V - allowing for the selection of the optimal load level for the object under test.

The resistance measurement range reaches up to 10 TΩ, and the test current goes up to 5 mA. This combination of parameters enables the inspection of the insulation state of large objects - high-power motors, power cables, or transformers - where low voltages might not excite a proper measurement.

Diagnostics and insulation condition assessment indices

In addition to the standard insulation resistance (IR) measurement, the meter determines a range of indicators that allow for assessing the condition of the dielectric over time:

• PI (Polarization Index) - polarization index calculated based on the ratio of results measured at a 10-minute interval,
• DAR (Dielectric Absorption Ratio) - dielectric absorption ratio for a shorter time interval,
• DD (Dielectric Discharge) - dielectric discharge index informing about leakage currents after disconnecting the voltage,
• SV (Step Voltage) - resistance measurement at a stepwise increasing test voltage, allowing for the detection of insulation degradation,
• RAMP - a test of gradually increasing voltage up to breakdown, enabling the assessment of dielectric strength.

Additionally, the device measures capacitance (5 nF - 50 µF for lower voltages), leakage current (range up to 5.50 mA), and AC/DC voltage in the range of ±30 V - ±600 V with a resolution of 1 V.

Communication and data logging

The KEW3127 is equipped with a Bluetooth module for wireless live transmission of results to a PC or Android devices. An optical USB connector enables wired communication with a PC. Built-in memory allows for recording a series of measurements with the possibility of later data export.

A large backlit display features an analog bar graph, which dynamically shows changes in resistance during the test - particularly useful during long dielectric absorption measurements. An interference reduction filter stabilizes readings even in environments with strong electromagnetic interference.

Robust construction and power supply

The meter is supplied in a hard carrying case providing an IP65 ingress protection rating. Power from the internal rechargeable battery allows for continuous operation for up to 10 hours at a load of 100 MΩ / 5000 V.

The device complies with the IEC61010-1 safety standard and is classified as CAT IV 600 V, meaning compliance with requirements for measurements at the source of the power installation. The manufacturer recommends calibration every 12 months.