THZ AC Power Series Suitable for Harsh Environment Applications

THZ AC Power Series Suitable for Harsh Environment Applications

Following the increasing demand for components suitable for critical environmental operating conditions and after rigorous development and testing, ICEL S.r.l. added a brand-new AC-Power series to the existing range. The THZ series is a solution for power applications at operating conditions with high temperature and high humidity levels associated with harsh environments. 

 

Main Project Targets

  • Excellent performances in AC-Power applications with high voltage and current ratings
  • Additional high performance under high temperature and humidity
  • Slight size increase compared to standard AC power series
  • Competitive price - radial boxed execution

 

Related Development Guidelines

  • Special finishing materials for added protection
  • Special film metallization design
  • Innovative production processes
  • Dedicated machines
  • Proper testing equipment

 

The Importance of Designing for Harsh Environments

High operation temperature and high humidity levels combined, even more with AC voltage operation, are particularly dangerous: a critical condition for metalized film capacitors.

If humidity reaches inside the units, electrochemical corrosion phenomena may occur, driven by the applied voltage. This may cause faster aging of the capacitor, with related parameters variation, potential body distortion, decrease of the expected lifetime, and rise of failure probability.

The higher the energy density of the component, the higher the detrimental effect, making it difficult to combine critical environmental stresses withstanding within reasonable sizes. It is necessary to minimize the humidity penetration in the capacitor, so that the related aging effects remain negligible for a long time, compared to the component expected lifetime and reliability.

Biased high temperature and high humidity tests are not yet mandatory proofs in plastic film capacitors normative but are in use for other categories of components (among them the “85/85/1000” test). Nevertheless, they are, often unproperly, also required by capacitor users, since critical environmental stress usage, together with high power stress, is rapidly increasing.

 

Humidity Tests Performed on the THZ Series

The main biased humidity tests taken as a reference for THZ design are:

  • AEC Q-200 cockpit test, 40°C 93% RH 1000h at rated voltage
  • 70/70/1000, 70°C 70% RH 1000h at rated voltage
  • IEC60068-2-67 humidity load test (Test Cy), 85°C 85% RH 504h at rated voltage
  • AEC Q-200 85/85/1000 (Level 1), 85°C 85% RH 1000h at a derated voltage

The new THZ series passed the above special tests with a moderate impact on the electrical parameters, where standard power series may rapidly show signs of corrosion. The new materials and technologies developed by ICEL S.r.l. additionally improve the performances, the reliability and the global capacitors' behavior under “normal” operating conditions is acquired know-how that is fundamental to the design of new capacitors series.

More information: ICEL S.r.l.