Home > Technical data > UL yellow cards > Explanatory notes
 EXPLANATORY NOTES
UL Classification
Performance Level Class (PLC)
LATI. S.p.A. - updated February 2000

file LATI: E 54080 (M)

HWI HOT-WIRE IGNITION

HVTR HIGH VOLTAGE-ARC TRACKING RATE

Mean Ignition Time (sec) Assigned PLC Tracking rate (mm/min) Assigned PLC
>= 120       0 > 0 ÷ < 10 0
>= 60 ÷

<

120 1 >= 10 ÷ < 25 1
>= 30 ÷   60 2 >= 25 ÷ < 80 2
>= 15 ÷   30 3 >= 80 ÷ < 150 3
>= 7 ÷   15 4 > 150 ÷      
>= 0 ÷   7 5            

HAI HIGH-AMP ARC IGNITION

D495 ARC RESISTANCE

Mean Number of arcs to cause Ignition Assigned PLC Mean Time of Arc Resistance (sec) Assigned PLC
>= 120       0 >= 420       0
>= 60 ÷

<

120 1 >= 360 ÷ < 420 1
>= 30 ÷

<

60 2 >= 300 ÷ < 360 2

>=

15 ÷

<

30 3

>=

240 ÷ < 300 3

>=

0 ÷

<

15 4 > 180 ÷ < 240 4
            > 120 ÷ < 180 5
            > 60 ÷ < 120 6
            > 0 ÷ < 60 7
CTI COMPARATIVE TRACKING INDEX  
Traking Index (Volts) Assigned PLC    

>=

600

     

0

   

>=

400
÷ < 600 1    

>=

250
÷ < 400

2

   

>=

175
÷ < 250

3

   

>=

100
÷ < 175

4

   

>=

0
÷ < 100

5

   

Col: Colour
Indicates the specific colour of the plastic material on which the "recognition" is applied.
NC (Natural Colour) indicates that only the unpigmented material is covered by the "recognition". ALL (All Colour) means that any possible colour has been recognized.
Min Thk mm: Minimum thickness (mm)
It represents the thickness of the specimen subjected to tests. It is an important indication as a number of properties are strictly dependent on the specimen thickness (e.g. the flammability according UL 94; HWI...)
UL 94: Flame Class
It is the classification of the material based on burning tests conducted in accordance with UL 94 (gas-burner test on small-scale specimen).
R.T.I.: Relative Temperature Index
It is an investigation of material with respect to retention of certain critical properties (e.g. dielectric,tensile, impact) as part of a long-time thermal ageing program, conducted according UL 746B. The temperature index shown in the individual recognition, indicates the temperature (°C) above which the material is likely to degrade prematurely.
The printed value refers to the extrapolation to 100.000 h. approx., with the retention at least of 50 % of its original value, after the ageing test. There are three different expression of the R.T.I. depending on the property requirements for a given application:electrical (Elec), mechanical with impact (Mech with imp) and mechanical without impact (Mech w/o imp).
HWI: Hot Wire Ignition
Performance is expressed as the mean number of seconds needed to either ignite standard specimens or to burn through the specimens without ignition.
The speciments are wrapped with resistance wire that dissipates a specified level of electrical energy.
HAI: High Amp Arc Ignition
Performance is expressed as the number of arc rupture exposures (standardized as to electrode type and shape and electric circuit) which are necessary to ignite a material when they are applied at a standard rate on the surface of the material.
HVTR: High Voltage Arc Tracking Rate
Is denoted as the rate, is mm/min, that a tracking path can be produced on the surface of the material under standardized test conditions. Note is made if ignition on the material takes place. The results of testing the nominal 3 mm thickness are considered representative of the material’s performance in any thickness.
D-495: Arc Resistance
In accordance with ASTM D-495 is expressed as the number of seconds that a material resists the formation of a surface conducting path when subjected to an intermittently occuring arc of high voltage, low current characteristics. The results of testing the nominal 3 mm thickness are considered representative of the material’s performance in any thickness.
CTI: Comparative Tracking Index
Is expressed as the voltage which causes tracking after 50 drops of 0,1% Ammonium Chloride solution have fallen on the material.
The results of testing the nominal 3 mm thickness are considered representative of the material’s performance in any thickness.
REMARKS
LATI does not guarantee that the data contained in this list are current, complete and error-free.
To double check the values, users are kindly requested to contact LATI Technical Assistance or commercial network.
LATI Industria Termoplastici S.p.A. declines all responsibility
arising from any use of the information described in this document.

Copyright © 2007 - LATI Industria Termoplastici S.p.A. - Registered office: via F. Baracca, 7 - I - 21040 VEDANO OLONA (VA)
Varese Company Register and Tax Code number 00214880122 - Share Capital € 3.818.400 i.v.
Tel. +39-0332-409111 - Fax +39-0332-409307 - email: info@lati.com - P.IVA IT00214880122