LT400

LT400 is a system designed to perform Partial Discharge Measurements on components (wires, plastic insulators, ...), windings, processes, final products (coils, motors, generators, transformers, etc.). It is a very useful tool in all phases of development and production of a new product (Design, Life Tests, Process Control, Quality Controls in production).

e.d.c. is the first European Company to study (since 1998) and propose new tests that allow identification of insulation problems between windings to stack and between turns of the same winding that the standard High Voltage and SURGE tests cannot identify. These problems produce failure of motors after short operating times (hours, days or weeks) in particular when the motor is driven by Electronic Speed Regulator (Inverter).

In addition to the test of stator/motors driven by Inverter, the Partial Discharge Measurements (in particular the PDIV Test) are useful in improving the quality of production processes of any type of motor or winding.

The PDIV test can, for example, be used to test copper/aluminium wires or insulating materials of different suppliers.

Also, it can verify the impregnation process by measuring the same stator before and after the impregnation process. For more information on this topic, request the Technical Note TN146_EDC_Partial_Discharge_Impregnation_Test.pdf that shows the results of tests performed on 4 windings produced with 4 different impregnation levels: none impregnation, impregnation with standard set-up, impregnation using less resin then standard, impregnation with a reduced solidification time.

"Quantify" how much the insertion of a phase separator or of the impregnation process or both, improves the insulation windings quality. This study, besides improving the knowledge of your product, is mandatory to define which class to guarantee your motor for use with inverters as required by EN60034-18-41. For more information on this topic, request the Technical Note TN147_EDC_Partial_Discharge_Insulation_Test.pdf that shows the results of tests performed on 4 standard stators with/without Impregnation and with/without phase separator.

Filter manufacturing defects that the classic tests of Dielectric Strength and Surge Test fail to locate. For more information on this topic request the Technical Note TN148_EDC_Partial_Discharge_Production_Test.pdf that study how windings failure can be easily identify using Partial Discharge Measurements in Production Tests. For more information on this topic request the Technical Note TN148_EDC_Partial_Discharge_Production_Test.pdf that study how windings failure can be easily identify using Partial Discharge Measurements in Production Tests.

Verify during the life/endurance test of the stators/motors after as many hours of life/endurance tests the insulating material begins to exhibit a permanent "degradation" of their insulating qualities. The PDIV test, long before a product failure, is able to evaluate materials and processes by verifying who has the worst quality, starting to degrade first. This is a new concept applied by major industries on products that must have a high level of reliability.

A significant advantage of using the LT400 is that it can be used to define in the laboratory the test parameters and the limits to be applied to the various Partial Discharge Measurements present in the EDC Testing Production systems. This can be done because both the hardware and the software level have a perfect compatibility between the LT400 and the various test systems in production: AST320W for stator - AAT320W for armature - AMT320W for motors.

Several versions of LT400 are available to test products from 2 to 8 output leads. In the basic version LT400 is managed by a Notebook; with option 320/PC the Notebook is replaced with an industrial computer.