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53

Wires & Cables

IEC 61034-1&2/ASTM E662 Smoke Density

This specifies a test for determination of smoke density. The “ 3 metre cube test ” measures the generation of smoke from electric cables during fire. A light

beam emitted from a window is projected across the enclosure to a photo cell connected to a recorder at the opposite window. The recorder is adjusted to

register from 0% for complete obscuration to 100% luminous transmission. A 1 metre cable sample is placed in the centre of the enclosure and is applied

with a fire. The minimum light transmission is recorded. The result is expressed as percentage of light transmitted. The specimen is deemed to pass this

test ( IEC 61034-1&2) if the value is greater than 60%. The higher the light transmittance, the less smoke emitted during a fire.

IEC 60754-2 Acidity

Acidity Test

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In this test, when the burner is heated to 800 C, 1g sample is placed inside and the HCl is absorbed into water inside the chamber fed with air flow. The water

is then tested with its acidity. If the hydrochloric acid yield is less than 5%, the cable is categorized as LSZH. If the hydrochloric acid yield lies between 5% to

15%, the cable is categorized as LSF. IEC 60754-1 cannot be used for measuring the exact HCl yield if it is less than 5% and thus cannot tell if the cable is

halogen free or not. To determine if the cable is halogen free, IEC 60754-2 should be used.

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This test specifies a method for the determination of degree of acidity of gases evolved during combustion of cables taken from the cable sample by measuring

its pH and conductivity. The specimen is deemed to pass this test if the pH value is not less than 4.3 when related to 1 litre of water and conductivity is less than

10 s/min. When the HCl yield lies between 2mg/g and 5mg/g, a cable specimen can pass IEC 60754-1 but its pH value may be less than 4.3 and therefore will

not pass the IEC 60754-2 test.

95% Visibility

No Visibility

(For example : EBXL - XLPO)

(For example : PVC)