UL 1676:2017 pdf free download – STANDARD FOR SAFETY Conductive-Path and Discharge-Path Resistors for Use in Radio-, Video-, or Television-Type Appliances.
5.4 Dielectric voltage-withstand test
5.4.1 Each resistor tested as specified in 5.1.1 — 5.3.2 shall be subject to the test specified in 5.4.2 —
5.4.5. The resistance of each resistor, measured at least 15 mm after the test and not more than 1 h after the test:
a) Shall be 12 MQ or less, and
b) Shall be within ±50 percent of the initial resistance measured. See 5.1.1.
5.4.2 The test potential applied to each resistor is to be 1000 V rms, sinusoidal, 60 Hz, and is to be applied across the resistor leads for 1 mm.
5.4.3 The test potential is to be obtained from a transformer that provides a variable output voltage. The applied potential is to be increased at a uniform rate from zero to the specified test value within 5 s. A manual or automatic means shall be used to control the rate of rise.
5.4.4 The sensitivity of the test equipment is to be such that when a resistor having a value of 120,000 2 is connected across the output, the test equipment indicates that the resistor has performed as intended for any output voltage less than the specified test voltage, and has not performed as intended for any output voltage equal to or greater than the specified test voltage.
5.4.5 In the event a resistor being tested dissipates more than rated power while the dielectric voltage-withstand potential is applied, cooling the resistor by artificial means complies with the requirement.
6 Conductive-Path Resistor Tests
6.1 General
6.1.1 The initial resistance of 10 as-received, conductive-path resistors is to be measured.
6.2 Humidity conditioning
6.2.1 Following the measurements specified in 6.1.1, the conductive-path resistors are to be subjected to the humidity conditioning as described in 5.2.2.
8 Strain Relief Test
8.1 One as-received resistor shall withstand, for 1 mm, without damage, a 22.2 N force applied in any direction possible to the leads or terminals.
9 Torque Test
9.1 A terminal, tab, or tang on one as-received resistor shall withstand, for 1 mm, without damage, a torque of 0.07 N.m applied at a right angle to the terminal, tab, or tang.
9.2 An axial wire lead on a resistor shall withstand the test specified in 9.3. The lead shall not break, and the resistor body shall not be damaged.
9.3 Each lead is to be bent through 90 degrees at a point 6.4 mm from the point of emergence of the lead. The radius of curvature of the bend is to be 0.8 mm. The free end of the lead is to be clamped to within 1.2 ±0.4 mm of the bend. The body of the resistor is then to be rotated through 360 degrees about its original axis. The rate of rotation is to be 2 — 5 s per 360 degrees. Successive rotations are to be in alternate directions. A total of three such 360 degrees rotations is to be performed after which the resistor is to be visually examined for evidence of lead breakage or damage to the resistor body.
RATING
10 General
10.1 A resistor shall be rated in ohms and watts.
10.2 For a discharge-path resistor only, the resistor intended for use in up to 125 V circuits shall not be rated less than 480 k2 or more than 12 MQ. A discharge-path resistor intended for use in 126 — 250 V circuits shall not be rated less than 960 kQ or more than 12 MQ.
10.3 For a discharge-path resistor only, the resistor shall be rated 1/2 W or greater.