They measure dielectric strength by applying up to 5kV on DC and 6kV on AC, injecting up to 30 or 100mA (500VA), insulation resistance up to 50GΩ, and electrical resistance from 1mΩ.  
Many wound components incorporate multiple coils, whether in three-phase systems or transformers with multiple windings. These testers can internally switch between the desired channels thanks to their built-in scanner. They also allow for pulse test measurements to determine potential insulation faults between turns. Prior to the test, they perform a check to ensure that the connections to the device under test are correct. These devices detect arc flash before it occurs.
Ensuring operator safety is paramount, and Chroma has designed a function to detect ground faults during dielectric strength tests using two current meters in differential mode. When the current difference exceeds the programmed value, the test stops, interpreting it as a current leak that could affect the user or the test environment.
The open/short circuit check before the electrical safety test ensures that a pass or fail result is truly due to the device under test and not to connection problems, such as those caused by wear, rust, or dirt on the contacts and/or wiring, which could lead to misidentifying good components as defective or vice versa.
Generally, each device to be tested offers a specific electrical capacitance, which is measured by the 19035 before the test. If this capacitance is not within the predefined range, the instrument interprets the connection as faulty and does not run the test.
The 19036 model incorporates a winding pulse test. This test applies a pulse that generates a damped resonant waveform based on the RLC components of the circuit. Analyzing this waveform identifies insulation failures or short circuits between the winding turns.
The 19035/6 series is designed to connect multiple devices or devices with multiple terminals, allowing for the selection and sequencing of measurements across different terminals/channels. For larger systems, external automatic switching devices with up to 40 channels, controlled from the meter itself, can be used.
It incorporates precise 2- and 4-wire resistance measurement by injecting DC current and can be used between channels, channels to ground, or even in star/delta configurations, eliminating the need for a dedicated device. Low-resistance measurements can incorporate temperature compensation to reduce the effect of resistance variations due to thermal changes. These meters
allow for checking the resistance balance in multi-phase devices. The DC resistance value is related to the inductance value. For example, when the three coils of a three-phase motor exhibit significant resistance differences, it causes irregular rotation and reliability issues. The Chroma 19035/6 testers detect the differences between the maximum and minimum resistance and whether these values ​​exceed the programmed value. In short, a valuable tool for detecting long-term reliability in engines.

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