Control—The following tests are useful for control purposes during the manufacture and use of varnishes, and for determining the uniformity of batches:

Specific gravity,

Viscosity,

Flash point, and

Nonvolatile matter by weight.

Performance—The following tests are useful for determining the performance of varnishes during application and use:

Drainage,

Time of drying,

Build,

Dielectric strength,

Thermal endurance,

Varnish compatibility,

Salt water proofness, and

Oil resistance.

1. Scope

1.1 These test methods cover tests for solvent containing varnishes primarily intended to provide electrical, mechanical, and chemical protection for electrical equipment. These test methods include tests for control and performance as follows:

1.2 Where the entire test method is included in this standard, the precision and bias are not known unless given in the stated method.

1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 5.

Note 1—There is no equivalent IEC standard.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

D56 Test Method for Flash Point by Tag Closed Cup Tester

D93 Test Methods for Flash Point by Pensky-Martens Closed Cup Tester

D149 Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at Commercial Power Frequencies

D202 Test Methods for Sampling and Testing Untreated Paper Used for Electrical Insulation

D287 Test Method for API Gravity of Crude Petroleum and Petroleum Products (Hydrometer Method)

D295 Test Methods for Varnished Cotton Fabrics Used for Electrical Insulation

D374 Test Methods for Thickness of Solid Electrical Insulation

D580 Specification for Greige Woven Glass Tapes and Webbings

D1475 Test Method For Density of Liquid Coatings, Inks, and Related Products

D1638 Method of Testing Urethane Foam Isocyanate Raw Materials

D1932 Test Method for Thermal Endurance of Flexible Electrical Insulating Varnishes

D2518 Specification for Woven Glass Fabrics for Electrical Insulation

D2519 Test Method for Bond Strength of Electrical Insulating Varnishes by the Helical Coil Test

D3145 Test Method for Thermal Endurance of Electrical Insulating Varnishes by the Helical Coil Method

D3251 Test Method for Thermal Endurance Characteristics of Electrical Insulating Varnishes Applied Over Film-Insulated Magnet Wire

D3278 Test Methods for Flash Point of Liquids by Small Scale Closed-Cup Apparatus

D3487 Specification for Mineral Insulating Oil Used in Electrical Apparatus

D5032 Practice for Maintaining Constant Relative Humidity by Means of Aqueous Glycerin Solutions

D5423 Specification for Forced-Convection Laboratory Ovens for Evaluation of Electrical Insulation

E104 Practice for Maintaining Constant Relative Humidity by Means of Aqueous Solutions

Keywords

build; dielectric strength; drainage; flash point; nonvolatile matter; oil resistance; solvent varnish; specific gravity; temperature index; time of drying; varnish; varnish compatibility; viscosity ; Viscosity--electrical insulating materials; Varnishes; Dielectric breakdown voltage; Drainage materials/systems; Drying time; Electrical insulating varnishes; Flexibility; Heating tests--electrical insulating materials; Nonvolatile matter content--paints/related coatings/materials; Oil resistance--electrical insulating materials; Specific gravity; Working viscosity

ICS Code

ICS Number Code 29.035.60 (Varnished fabrics)

Citing ASTM Standards

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