Xenon arc or Fluorescent based UV weathering test chamber in compliance with ISO 4892-3 or ISO 4892-2.
These Lamps are mounted in two banks of four each, are rich in Ultra-Violet energy between 280-350 watts at an operating voltage of 220 volts
An electrical discharge within the tube generates Ultra-violet energy at 254 Nano meters which excites the Phosphor coating causing it to fluoresce & radiate approx. 85% of the lamp’s energy between 280-350 Nano meters. In the natural sunlight spectrum below 350 NM, accounts for only about 3% of the total radiant energy.
The UV below 310 NM produced by these lamps at sample face (50mm from the lamp) is several times greater than that of natural sunlight & is the principal cause for acceleration in a test.
The fluorescent sun lamp produces virtually no significant visible or infra-red energy. Lamp Intensity normally deteriorates by about 20% during 1600 hours of useful life & the lamps are changed on a rotation basis. Every 400 hours a new Lamp is installed in each bank of 4. This method ensures reasonably uniform radiation at the sample face.
✓ A Programme Timer automatically controls the UV & Condensation cycles of the UVCON & programming.
✓ Each has Programme Cycle typically 24 hours of UV followed by four hours of condensation.
✓ Temperature is measured & controlled by a solid state circuit. A PT-100 Sensor is mounted in a black aluminium panel on the specimen rack.
✓ The temperature is set by the Operator & monitored by Digital panel meter on the Control Panel.