BS EN 60974-12-2011 pdf download.Arc welding equipment Part 12 : Coupling devices for welding cables.
The coupling device shall withstand storage and transport at an ambient air temperature of —20 °C to + 55 C without any damage to function and performance.
5 Type tests
5.1 Test conditions
All type tests shall be carried out on the same new and completely assembled coupling device.
All type tests shall be carried out at an ambient air temperature between 10 DC and 40 °C.
The accuracy of measuring instruments shall be:
a) electrical measuring instruments: class 1 (± 1 % of full-scale reading), except for the measurement of insulation resistance and dielectric strength where the accuracy of the instruments is not specified, but shall be taken into account for the measurement:
b) temperature measuring devices: ± 2 K.
5.2 Test sequence
The type tests given below shall be carried out in the following sequence:
a) general visual inspection;
b) temperature rise, see 8.1;
c) crush strength. see 9.5;
d) insulation resistance, see 7.2;
e) dielectric strength, see 7.3.
The other type tests in this part of IEC 60974 not mentioned above may be carried out in any convenient sequence.
6 Designation
Coupling devices shall be designated by the range of cross-sectional area of the welding cable intended to be connected. The test current at an ambient air temperature of 40 DC is given in Table 1 based on maximum cross-section area. The welding coupling device shall accept the minimum cross-sectional area as given in Table 1. Minimum cross-sectional area may be reduced to extend the coupling device fitting range.
Conformity shall be checked by the following test.
The coupling device is wiped clean and tightly wrapped In a metal foil covering the external surface of the insulation.
The a.c. test voltage shall be of an approximate sine waveform with a peak value not exceeding 1,45 times the r.m.s. value, having a frequency of 50 Hz or 60 Hz, applied for 1 mm between the live parts and the metal foil.
7.3.2 Additional requirements for striking and stabilizing voltage rating
For couplers for use with arc striking and stabilizing voltage, the insulation shall withstand the rated peak arc striking and stabilizing voltage as rated by the manufacturer. The insulation shall withstand a high frequency voltage of pulse width 0,2 .is to 8 is, a repetition frequency of 50 Hz to 300 Hz and shall be 20 % higher than the rated peak arc striking and stabilizing voltage as determined by the manufacturer.
Conformity shall be checked by the following test.
For couplers intended for use with arc striking and stabilizing voltage, the couplers shall be subjected to the high-frequency test voltage. The full value of the high-frequency voltage is applied for 2 s between the electrode circuit and
a) conductive surfaces:
b) other isolated circuits.
Flashover or breakdown shall not occur. Any discharges unaccompanied by a voltage drop
(corona) are disregarded.
Alternatively, for couplers intended for use with arc striking and stabilizing voltage, an ac.
test voltage of approximately sine waveform at 50 Hz or 60 Hz may be used.
7.4 Protection of live parts against unintentional contact
Parts designed to carry welding current and likely to be live after disconnection shall be recessed to a depth of at least 10 % of the Internal diameter of the insulation with a minimum depth of 2 mm with respect to the insulating body.
As a consequence, insulation has to be able to withstand normal service conditions so that the protecting length is maintained during the life of the coupling device.
Conformity shall be checked by linear measurement and visual inspection,
8 Thermal rating
8.1 Temperature rise
The temperature rise caused by the current passing through a coupling device normally coupled and fitted with an untinned copper welding cable of maximum cross-sectional area as indicated in Table 1 shall not exceed 45 K at the hottest spot of the external surface.
Conformity shall be checked by the following test.
The coupling device Is normally coupled and fitted with at least 2 m long welding cables. The coupling device is suspended by its welding cables from two wooden laths 1 m apart, hanging between the two laths in the horizontal plane about 200 mm above the ground in a draught- free area.
A continuous d.c. current equal to 75 % of the test current (equivalent to approximately 60 %
duty cycle) is passed through the coupling device until the rate of the temperature rise does
not exceed 2 K/h. During the total test time, the d.c. current shall be kept constant with a
tolerance of ± 2 %.
8.2 Resistance to hot objects
The Insulation shall be capable of withstanding hot objects and the effects of a normal amount of weld spatter without being ignited or becoming unsafe.BS EN 60974-12-2011 pdf download.