Electrical Testing
In house electrical testing capabilities include ASTM D150 dielectric properties and ASTM D257 volume/surface resistivity. Both tests are typically non-destructive.
Volume/Surface Resistivity ASTM D257 is a convenient way of assessing electrical leakage at a component level. Standard chemical exposures (ASTM D543/D471), can be performed to evaluate the effects of disinfectants or humidity on the electrical leakage of the materials. MAP Labs utilizes a Keysight 16008B Resistivity Cell with a full complement of planar electrodes (26, 50, and 76mm Main Electrodes and 38, 70, 88mm guard electrodes). In Volume Resistivity mode an electric potential, typically 500V, is introduced across the thickness of the test specimen; the current flow through the sample is recorded and used to calculate the volume resistivity of the specimen. The standard reporting is to calculate the volume resistivity after 60 seconds of electrification. When in Surface Resistivity mode the test operates the same way except the electrical potential is applied between the main on guard electrodes on the same side of the test specimen.
Dielectric Properties ASTM D150 provides the dielectric constant and loss factor among other valuable metrics. The dielectric constant is a measure of how polarizable the material under test is relative to vacuum. The dielectric constant increases with dipole / ion / acid swell and can be used as an additional measure of chemical compatibility. In house testing is performed with a Keysight 16451B dielectric test cell with full range of electrode accessories and a Keysight LCR meter.
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Reference Charts: Volume and Surface Resistivity
Example Results: Volume and Surface Resistivity
Relevant Methods:
Specimen Conditioning:
- ASTM D257 - Standard Test Methods for DC Resistance or Conductance of Insulating Materials
- ASTM D150 - Standard Test Methods for AC Loss Characteristics and Permittivity (Dielectric Constant) of Solid Electrical Insulation
Specimen Conditioning:
- ASTM D618 - Standard Practice for Conditioning Plastics for Testing
- ASTM E104 - Standard Practice for Maintaining Constant Relative Humidity by Means of Aqueous Solutions
- ASTM D5032 - Standard Practice for Maintaining Constant Relative Humidity by Means of Aqueous Glycerin Solutions