PRODUCT CONTROL   All our products undergo individual inspections at the end of the manufacturing line. Their dimensions, mechanical and electrical characteristics are checked to standard NFC 79-620. In addition, each constituent element of our products is subjected to cold testing. Dimensional inspections The tolerances are adapted to the intended use and are specified on the manufacturing drawings.   Electrical inspections Circuit power testing by cold resistance measurements. Tolerance allowed : -5% and +10% of the nominal resistance value Testing of insulation between live parts and the earth. The test is conducted under a direct voltage of 500 V. The minimum cold values upon release from the company are greater than 100 Megohms. Testing of dielectric insulation between live parts and the earth. The test is conducted under an effective alternative voltage which is equal to twice the nominal voltage plus 1000 V. No warping or perforation must be found during the test. Reading of the nominal operating temperature. (on request) The stray current and the hot dielectric rigidity can be measured on a sample. Specific conditions of utilisation (total power number of circuits in the assembly temperature) may lead to stray current values which require special measures.     Mechanical inspections Non destructive test Visual inspections of heating elements. Weld tightness inspections : in hydraulic chambers with a maximum diameter of DN 700 or 28 in. and maximum pressure equal to 40 bar helium tightness test with mass spectrometer dye penetrant testing X-ray inspections of welds where applicable.