to determine the fire resistance by the fire hazard test
in accordance with IEC6 0695-2-10 :2000 ～ IEC6 0695-2-13 :2000
and further standards and regulations listed in the
STANDARDS SCHEDULE T 03e
The test procedure is used to examine the fire
resisting properties of products if, during the application
or in the case of a fault, heated or glowing parts could be considered as a short-time ignition source. Loose connections or bad contacts cause punctually high temperatures on electrical articles, their
components and their parts. Attention should also be paid to
the fire risk in connection with textile seat coverings,
tablecloths, or curtains.The PTL glow wire test apparatus is suitable for lighting equipment, low-voltage
electrical appliances, household electrical appliances, machine tool electrical
appliance, motor, electric tools, electronic instruments, electrical
instruments, information technology equipment, electrical business equipment,
electrical connections and accessories and other electrical and electronic
products and components of the research, production and
quality Inspection department, also suitable for insulation plastic
materials,
Test Apparatus
The ignition source is imitated by an electrically
heated wire loop against which the sample is pressed with
a constant force. A miniature jacket thermocouple
serves as a sensor for the loop temperature. The sample has to be fastened to a carriage on
which, by means of a tensioning cord, a weight with a force of 1 N is effective in the direction of
the wire loop. Scales enable the reading of the flame height and the depth of penetration. Approx.
200 mm below the wire loop a board of pine wood, covered with a layer of tissue paper, is
mounted. This device enables to judge the danger of a fire spreading through burning drops or
glowing parts falling from the sample.
Standard outfit :
1 wire loop of nickel-chromium, with clamping
mechanism,
1 carriage with Cardanic holding device for the
specimen, five-fold adjustable,
1 rail system with ground running surfaces,
1 fine rope pull mechanism with weights for loads
of 1 ± 0,2 N,
1 indicating device for the depth of penetration,
with maximum pointer and stop,
1 scale to measure the flame height, multiple
adjustable,
1 high current isolating transformer to heat the
wire loop, with series connected variable ratio transformer, to set the temperature
up to 960 °C,
1 miniature jacket thermocouple Chromel-Alumel,
with plug almost free from thermoelectric voltage and with compensating lead,
1 temperature indicating instrument to indicate the
temperature of the glow-wire loop, with digital display, measuring range 0...1000 °C,
class 0,5, built-in operable, see Fig.
1 and 3, can be recalibrated, with compensation of
the ambient temperature.
1 housing, desk shaped, with all necessary electrical components, with safety switct
PULSE TIMER WITH TIME DISPLAY
The pulse timer is started by a push button at the
same time as the specimen contacts the loop. By that, the indication of the time begins to run.
The minutes and the seconds appear on the display in numerals which are good to read. At the first
signal, the specimen has to be returned. At
each following signal, the flame height has to be
observed. The pulse timer can be switched off by pressing the button "STOP". By means
of a switch it is possible to preselect, if the glow-wire heating shall be automatically interrupted at the
first signal. See Fig. 1 and 3.
MOTOR DRIVE
for slowly moving up the specimen to the wire loop ,and for returning to the starting position at aconstant speed As soon as the specimen contacts the loop, a
coupling releases the carriage. After an operation time of exactly 30 seconds, the carriage is
automatically returned. The test results are better reproducible, and the laboratory technician's
attention is not diverted during the testing procedure by having to do various operation tasks. He can
fully concentrate on the observation of the specimen.
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