BS EN IEC 60974-2 pdf free download
BS EN IEC 60974-2 pdf free download.Arc welding equipment.
6.4.10 Supply coupling device (attachment plug) If a supply coupling device is provided as a part of the LIQUID COOLING SYSTEM, its rated values shall be not less than the maximum effective supply current 1eff. For supply networks up to 125 V, the rated current shall, additionally, not be less than either a) or b): a) 70 % of the rated maximum supply current; b) 70 % of the supply current, as measured with the fan motor or pump stalled, whichever is greater. Conformity shall be checked by visual inspection, measurement and calculation. 6.5 Leakage current between welding circuit and protective earth With the cooling system flled with the cooling liquid specified by the manufacturer (see 12.1 e)), the leakage current from the torch to the protective earth connection of the cooling system shall not exceed 10 mA DC. Conformity shall be checked by applying a DC voltage of 500 V at room temperature between the protective earth connection and a copper pipe to simulate the torch connected to the outlet of the cooling system by a hose with a maximum length of 0,5 m as shown in Figure 1. The minimum inner diameter of the hose shall be 5 mm. The minimum length of the copper pipe shall be 10 cm with a minimum internal diameter of 5 mm. The cooling system and the simulated torch are flled with liquid for the test. The pump is operating.7 Mechanical provisions 7.1 General As specified in Clause 14 of IEC 60974-1:2017. The test shall be carried out with cooling liquid. 7.2 Cooling liquid overflow When flling the cooling system in accordance with the manufacturer’s instructions, overflow or spillage shall not result in electric shock. Conformity shall be checked by the following treatment and test. The liquid container is completely filled. A further quantity of liquid equal to 15 % of the capacity of the container or 0,25 , whichever is the greater, is then poured in steadily over a period not to exceed 60 s. Immediately after this treatment, the equipment shall pass the dielectric strength test of 6.1.5 between input circuits and exposed conductive parts. 7.3 Hose coupling devices and hose connections . If hose coupling devices or hose connections, which often have to be undone, are placed above or near to live parts, these live parts shall be protected from cooling liquid by splash proof enclosures, with drains or other appropriate measures. An exception is made for live parts of the welding circuit. 8 Cooling system 8.1 Rated maximum pressure The manufacturer shall determine the rated maximum pressure attainable by the cooling system (see 11.3 c), box 12). Conformity shall be checked by measuring the pressure when the outlet is blocked.9 Abnormal operation 9.1 General requirements A cooling system shall not break down and increase the risk of electric shock or fire under the conditions of operation of 9.2. These tests are conducted without regard to temperature attained on any part, or the continued proper functioning of the cooling system. The only criterion is that the cooling system does not become unsafe. These tests may be conducted on any cooling system that functions correctly. The cooling system， protected internally by， for example， a circuit-breaker or thermal protection，meets this requirement if the protection device operates before an unsafe condition occurs. Conformity shall be checked by the following tests. a) A layer of dry absorbent surgical type cotton is placed under the cooling system, extending beyond each side for a distance of 150 mm. b) Starting from the cold state, the cooling system is operated in accordance with 9.2. c) During the test, the cooling system shall not emit flames, molten metal or other materials that ignite the cotton indicator. d) Following the test and within 5 min, the cooling system shall be capable of withstanding a dielectric test in accordance with 6.1.5 b) of IEC 60974-1:2017.BS EN IEC 60974-2 pdf download.
