GB/T 1695-2005 Rubber, vulcanized - Determination of electrical breakdown strength and voltage resistant at commercial power frequency
Warning—— Persons using this standard shall be familiar with normal laboratory practice. 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 to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions.
1 Scope
This standard is applicable to the calculation of breakdown strengths by measuring the breakdown voltages of the specimens which are applied with AC power continuously in a continuous uniform or level-by-level boosting mode. The voltage is raised to a specified value by the rapid voltage boosting method, and then kept for a certain time. If the specimen is not broken, such specified value is set as the voltage resistant.
2 Normative References
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections) to, or revisions of, any of these publications do not apply to this standard. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition applies.
GB/T 2941 GB/T 2941 Rubber - Standard temperatures, humidities and times for the conditioning environmental and testing of test pieces (GB/T 2941-1991, eqv ISO 471: 1983)
GB/T 5723 Rubber, vulcanized or thermoplastic - Determination of dimensions of test pieces and products for test purposes (GB/T 5723-1993, eqv ISO 4648: 1991)
GB/T 9865.1 Rubber, vulcanized or thermoplastic - Preparation of specimens and test pieces - Part 1: Physical tests (GB/T 9865.1-1996, idt ISO 4661-1: 1993)
3 Terms and Definitions
For the purposes of this standard, the following terms and definitions apply.
3.1
voltage resistant
the voltage is raised to a specified value by the rapid voltage boosting method, and then kept for a certain time. If the specimen is not broken, such specified value is set as the voltage resistant, expressed in kV
3.2
breakdown voltage
the specimen is broken down under the action of a certain voltage, and the voltage value at this time is called the breakdown voltage, expressed in kV
3.3
electrical breakdown strength
ratio of the breakdown voltage of the specimen to its thickness, expressed in kV/mm
4 Test apparatus
See Figure 1 for the schematic diagram for test circuit.
K1—— Power switch;
T1—— Regulating transformer;
V—— Voltmeter;
T2—— High voltage transformer;
K2—— Overcurrent relay;
A—— Upper electrode;
B—— Lower electrode;
Rx—— Specimen.
Figure 1 Schematic diagram for test circuit
Foreword i
1 Scope
2 Normative References
3 Terms and Definitions
4 Test apparatus
5 Specimen
6 Time interval between vulcanization and test
7 Test medium
8 Test procedure
9 Test results
10 Test report