To confirm that unarmoured elastomeric and/or plastics insulated cables, with a semi-rigid or tough sheath, are suitable for use in metering pumps, dispensers and remote pumping units. Unless otherwise specified these tests are to be performed at (20 ± 5) °C. For criteria, see 5.3.2.4.
6.1.4.2 Solvent test
Samples of the cable shall be exposed for a minimum of 176 h to the vapours of solvents as listed below:
methanol;
ethanol;
unleaded petrol according to EN 228.
Separate samples shall be used for each solvent. Where a metering pump or dispenser is intended for use with biodiesel blends above 20 %,separate samples of the cable shall be immersed in 100 % FAME (biodiesel) conforming with EN 14214 for a minimum of 176 h.
The total exposure time shall be made up of one period of (66 ± 2) h and seven periods of (17 ± 1) h, in this order.
Each exposure period shall be followed by a drying period, where the sample is removed from the solvent vapour/fuel and is subjected to forced draft ventilation in fresh air for a minimum period of 6 h.
Inspect the cable and record findings.
6.1.4.3 Impact test
Within one hour of the completion of the (66 ± 2) h period solvent test, the sample shall be positioned on the steel base of the apparatus shown in Figure 7 and underneath the hardened steel intermediate piece.
Key
1 hammer 2 hardened steel 3 sample
Figure 7 — Test set-up for the impact test
A hammer with a mass of 1 kg shall be caused to fall onto the hardened steel intermediate piece through a height of h = 0,5 m. The sample shall be removed from the apparatus.
Examine sample under a magnification of × 10 and record findings.
A test voltage in accordance with Table 2, a) or Table 2, b) shall be applied for (600+5) s, between each conductor in turn and the remaining conductor or the remaining conductors connected together.
Verify if the sample withstands the voltage test and there is no breakdown of the applied voltage, record results.
Table 2 — Test voltages
Cable Voltage Rating Test Voltage
a) For electrical apparatus having a nominal supply voltage not exceeding 90 V peak 500 Vrms (0+5) % b) For electrical apparatus having a nominal supply voltage (Unrms) greater than 90 V
peak (1 000 + Un) Vrms (0+5) %
c) For electrical apparatus having a nominal supply voltage (Unrms) greater than 90 V
peak (1 500 + 2 Un) Vrms (0+5) %
6.1.4.4 Low temperature bend test
Within 2 h of the end of the final drying period of the solvent/fuel test, a sample of cable of suitable length shall be taken and shall be maintained at (-20 ± 2) °C, or at lower extended temperature as declared by the manufacturer, for a period of not less than 4 h. At the end of this period, and whilst still in the refrigerated compartment, the sample shall be bent through 90° round a bending mandrel, then bent through 180° in the opposite direction over a second bending mandrel and straightened to its original position, all the bending operations being carried out in the same plane.
This cycle of operations shall be performed twice.
NOTE For operator safety it is recommended the bending operation be performed using thermally insulated gloves.
After removal from the refrigerated compartment the sample shall be examined under a magnification of × 10 and the state of the sample shall be recorded.
6.1.4.5 Voltage and insulation resistance tests 6.1.4.5.1 General
The sheath of the cable sample used in the bend test shall be wrapped in a thin metal foil. To avoid voltage stressing, the foil should terminate at least 25 mm away from the end of the sheath at the end of the cable.
6.1.4.5.2 Voltage test
A test voltage in accordance with Table 2, a) or Table 2, c) as appropriate shall be applied for (600+5) s between each conductor in turn and the metal foil and remaining conductors.
Observe test voltage source for evidence of breakdown of the sample, record results.
6.1.4.5.3 Insulation resistance test
The insulation resistance of the sample used in 6.1.4.5.2 shall be measured immediately after the completion of test in 6.1.4.5.2.
The resistance of the insulation shall be measured between each conductor in turn and the metal foil and remaining conductors by means of a d.c. voltage of 500 V. Record the resistance values.
6.1.4.6 Flame transmission tests for cables 6.1.4.6.1 General
Any certified Ex d cable entry is suitable for the subsequent testing.
6.1.4.6.2 Test apparatus
An approximately cubic sealed vessel having a net volume in the range of 1 l to 10 l, but not less than that of the largest cable termination enclosure to be installed within the metering pump, dispenser or remote pumping unit, with a number of holes in the side walls adapted to suit the entry devices under test, or to permit blanking off if not required. The vessel shall be equipped with gas entry and exit ports and with an ignition device to ignite the gas centrally.
6.1.4.6.3 Test cables
If the tests are intended to apply to ranges of specified type of cable, the samples of cable used in the tests shall include:
3 cores of the largest cross-sectional area conductors that can be accommodated; and
the largest number of the smallest cross-sectional area conductors that can be accommodated.
If the tests are intended to cover unspecified cables, or cables where the cable cross section may be expected to have gaps or leakage paths, the test cable may be either as mentioned above or be a specially prepared test sample as described below, whichever is considered by the testing authority to be the most onerous.
The sample of test cable shall be prepared and fitted into the cable entry device in accordance with the entry device manufacturer's instructions, and to the dimensions shown in Figure 8.
Cable tails left unsecured shall be capped off to seal from hot gases. Length 2,5 × D1 where D1 = wire diameter including insulation. Total length of wires 25 × D1 ± 10 %. If screened wires screened part length is 2,5 × D1. Diameter of inner sheath is D2. Length of inner sheath shall be equal to D2 ± 10 %.
Cable outer diameter is D3.
The cable length outside the gland shall be 20 × D3 ± 10 %.
Figure 8 — Test set-up for flame transmission test 6.1.4.6.4 Test gases
The test gas mixtures shall be according to EN 60079-1:2007, 15.2 for equipment of Group IIA.
6.1.4.6.5 Temperature
The temperature of the cable cores shall be raised, by any convenient means, to 70 °C for the duration of the tests.
This requirement may be waived by the testing authority if it is satisfied that the materials and construction of the cable are such that elevation of the cable temperature will not increase the possibility of flame transmission during the test.
6.1.4.6.6 Procedure
The cable/cable entry combination shall be attached to the test vessel.
The test vessel shall be placed inside an outer chamber, and both the test vessel and the outer chamber are filled with the test gas.
The cable shall be raised to the test temperature.
The test gas within the test vessel shall be ignited.
The above test sequence shall be repeated 4 times.
Observe for ignition of the gas external to the test vessel and record findings.