IEC 60227-2:2003 pdf download.PolyvinyI chloride insulated cables of rated voltages up to and including 450/750 V
3.1.2 Apparatus
This test shall be carried out by means of the apparatus shown in figure 1. This apparatus consists of a carrier C, a driving system for the carrier and four pulleys for each sample of cable to be tested. The carrier C supports two pulleys A and B，which are of the same diameter. The two fixed pulleys, at either end of the apparatus, may be of a different diameter from pulleys A and B, but all four pulleys shall be so arranged that the sample is horizontal between them. The carrier makes cycles (forward and backward movements) over a distance of 1 m at an approximately constant speed of 0,33 m/s between each reversal of the direction of movement.
The pulleys shall be made of metal and have a semi-circular shaped groove for circular cables and a flat groove for flat cables. The restraining clamps D shall be fixed so that the pull is always applied by the weight from which the carrier is moving away. The distance from one restraining clamp to its support, while the other clamp is resting on its support, shall be of 5 cm maximum.
The driving system shall be such that the carrier turns smoothly and without jerks when it reverses from one direction to another.
3.1.5 Voltage between cores
For two-core cables the voltage between the conductors shall be about 230 V a.c. For all other cables having three or more cores, a three-phase a.c. voltage of about 400 V shall be applied to three conductors, any additional conductors being connected to the neutral. Three adjacent cores shall be tested. In case of a two-layer construction, they shall be taken from the outer layer. This also applies when a low voltage current loading system is used.
3.1.6 Fault detection (construction of the flexing apparatus)
The flexing apparatus shall be constructed so that it will detect and stop if the following occurs during the flexing test:
interruption of the current;
一short circuit between the conductors;
一short circuit between the test sample and the pulleys (flexing apparatus).
3.2 Bending test
The requirements are given in 5.6.3.2 of IEC 60227-1.
A sample of cord of appropriate length shall be fixed in the apparatus as shown in figure 2, and loaded with a weight having a mass of 0,5 kg. A current of about 0,1 A shall be passed through the conductors.
The sample shall be bent backwards and forwards in a direction perpendicular to the plane of the axes of the conductors, the two extreme positions making an angle of 90° on both sides of the vertical.IEC 60227-2 pdf download.