IEC 60702-2 pdf download

IEC 60702-2 pdf download Mineral insulated cables and their terminations with a rated voltage not exceeding 750 V — Part 2: Terminations
5.1.3Explosive atmospheres
A seal for use in potentially explosive atmospheres shall, in addition to complying with therequirements of this standard, also satisfy the appropriate requirements specified in IEC 60079-0.
5.1.4corrosion resistance
A seal or enclosure shall be made from material which will ensure freedom from corrosionarising from electrolytic action.
5.1.5Test requirements
The material used in the seal shall be such that the completed seal is capable of meeting thetest requirements specified in this standard.
5.1.6operating temperature
The conductor insulation shall be suitable for the range of operating temperatures stated forthe seal by the manufacturer.
5.2Glands
5.2.1 Material
A gland may be of any suitable material providing that it ensures freedom from corrosionarising from electrolytic action and meets the test requirements specified in this standard.
5.2.2Thread form
The gland entry threads shall have a preferred thread form in accordance with those specifiedfor conduit in iEC 60423.Other threads are permitted provided that the gland complies withall the other requirements of this standard.
5.2.3 Entry thread length
The length of gland entry threads shall be not less than 8 mm.
5.2.4Explosive atmospheres
Glands for use in potentially explosive atmospheres shall,in addition to complying withthe requirements of this standard，also satisfy the appropriate requirements specified inlEC 60079-o.
6Type tests
6.1General
The tests in this standard are type tests intended to establish termination design charac-teristics.Unless otherwise specified,all tests shall be carried out at an ambient temperatureof (20±10)c.
The test voltage shall be either a.c. of approximately sinusoidal waveform at a frequency inthe range 49 Hz to 61 Hz,or d.c.equal to the peak value of the alternating voltage,and shallbe applied gradually-
The seals and glands to be tested shall be fitted in accordance with the manufacturer’srecommendations to both ends of (300 ±50) mm lengths of cable complying with IEC 60702-1,of a size and rated voltage appropriate to the seals/glands under test.Each seal shall befitted as soon as possible after the end of the cable has been prepared, to minimize theingress of moisture.
New seals/glands shall be taken for each electrical and mechanical test.
6.2Seals
6.2.1Voltage test
The sample shall withstand the following test voltage applied between each conductorand every other conductor，and between all conductors bunched together and the sheath,for 5 min:
– 2 000 v r.m.s. for seals for 50o v cable;- 2 500 v r.m.s. for seals for 750 V cable.
6.2.2Insulation resistance test
The insulation resistance measured with a d.c. voltage between 80 V and 500 v appliedbetween each conductor and every other conductor,and between each conductor and thesheath shall be not less than 100 Mo2.
6.2.3 Insulation integrity test
This test shall be carried out，in addition to the insulation resistance test after the environ-mental tests specified in 6.2.4 and 6.2.5, as an indirect check that the insulation has notdeteriorated.
The insulation integrity test is a voltage test applied between each conductor and every otherconductor and between each conductor and the sheath. A voltage equal to the rated voltageof the cable shall be applied for 5 min. No insulation breakdown shall occur.