Datasheet

622
PHOENIX CONTACT
IEC 60210-1/UL 746 B
Insulation material properties
In the following tests, an increased load
on the terminal block is simulated over a
longer period of time. The behavior of
plastics at constantly higher temperatures is
described with respect to their tensile
strength and insulation properties. IEC
60216 and UL 746 B specify a temperature
index that allows conclusions to be drawn
regarding the service life of plastics under
thermal loads. Characteristic values are
specified for both properties:
– Mechanically as a TI value according to
IEC 60216
– Electrically as an RTI value according to
UL 746 B
IEC 60216 – TI value
The tensile strength is measured over
5000 hours and the result is extrapolated to
20,000 hours. After 20,000 hours, the
temperature is recorded at which the
tensile strength decreased by half.
UL 746 B – RTI value
The RTI (elec.) indicates the highest
operating temperature before a disruptive
discharge occurs under certain test
conditions. The polyamides used by
Phoenix Contact are classified as follows:
Ceramic terminal blocks, for example, are
available for use at higher temperatures.
UL 94 V2 UL 94 V0
TI 105°C 125°C
RTI 125°C 130°C
ASTM E 162
Surface inflammability
The spread of a fire under the influence of
heat is tested and evaluated in the above
standard.
To evaluate the surface inflammability of
plastics, a “flame spread index” is devised
according to ASTM E 162 to provide
information on flame propagation under
given test conditions.
For this purpose, a sample (152 x 457 x
maximum 25.4 mm) is irradiated with a heat
source (815°C) at an angle of 30° and
ignited with a naked flame at the top end.
During the 15-minute duration of the test,
the time in which the flame front reaches
two measuring points that are 76 mm apart
is determined. The product of this flame
propagation time and a calculated heat
development factor yields the “flame spread
index”.
In the American railroad sector, the
maximum limit value is 35. In this test, the
drip behavior of the plastic is also observed
and evaluated.
The terminal blocks from Phoenix Contact
achieve a flame spread index of 5, drip
without burning, and are therefore well
below the maximum permitted values of
the Federal Railroad Administration (FRA)
of the US Department of Transportation.
Radiant heater
Flame
Plastic sample
Technical information
Quality tests