BS EN IEC 60974-5:2019 pdf free download – Arc welding equipment
5.2 Measuring instruments
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 measuring instruments is not specified, but shall be taken into account for the measurement;
b) thermometer: ±2 K;
c) tachometer: ±1 % of full-scale reading;
d) pressure measuring instruments: class 2,5 (±2,5 % of full-scale reading).
5.4 Type tests
All type tests given below shall be carried out on the same WIRE FEEDER .
As a condition of conformity, the type tests given below shall be carried out in the following sequence:
a) visual inspection (as defined in 3.1 .7 of IEC 60974-1 :201 7);
b) insulation resistance (as specified in 6.1 .4 of IEC 60974-1 :201 7 (preliminary check));
c) enclosure (as specified in 1 4.2 of IEC 60974-1 :201 7);
d) handling means (as specified in 1 4.3 of IEC 60974-1 :201 7);
e) drop withstand (as specified in 1 4.4 of IEC 60974-1 :201 7);
f) protection provided by the enclosure (as specified in 6.2.1 );
g) insulation resistance (as specified in 6.1 .4 of IEC 60974-1 :201 7);
h) dielectric strength (as specified in 6.1 .5 of IEC 60974-1 :201 7);
i) visual inspection (as defined in 3.1 .7 of IEC 60974-1 :201 7).
The other tests included in this document and not listed here shall be carried out, but may be completed in any convenient sequence.
Adequate drainage shall be provided by the enclosure. Retained water shall not interfere with the correct operation of the equipment or impair safety. The quantity of water that may enter the enclosure during the following test is not limited. Conformity shall be checked by the following test: The filler wire shall be fed into the drive system and all external connectors shall be connected or covered. The WIRE FEEDER shall be subjected to the appropriate water test without being energized. Immediately after the test, the WIRE FEEDER shall be moved to a safe environment and subjected to the insulation resistance test, listed in 5.4 g) and to the dielectric strength test, listed in 5.4 h). When live parts at welding potential are protected against precipitation, the filler wire shall show no visual wetness after the test.
Connection of exposed conductive parts to the protective conductor is required if the WIRE FEEDER is rated for supply voltages above SELV. The protective conductor connection shall be secured to the frame or enclosure by a screw or fastening that shall not require removal during any servicing operation. Solder alone shall not be used for securing the protective conductor terminals. This terminal shall not be used for any other purpose (such as for clamping two parts of the casing together). The welding circuit and conductive parts connected to the welding circuit shall not be connected to the protective conductor.