MIL-PRF-22684 Resistors, Fixed, Film \(Insulated\) General Specification ForThis specification covers the general requirements for insulated, film, fixed resistors of 2- and 5- percent resistance tolerance. These resistors are capable of full-load operation at an ambient temperature of 70 degrees C and have a resistance-temperature characteristic of +200 parts per million per degree Celsius \(ppm/degrees C\), \(see 6.1\). Designers are CAUTIONED on using these resistors in high power pulse applications \(see 6.10\).

Pages 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14

MIL-PRF-22684F

4.6.5 Short-time overload (see 3.10).

a. Test conditions:

(1) Free space: In free space, resistors shall be mounted horizontally, with no object closer than 3 inches

(76.2 mm) to the protective coating except the mounting base that shall not be closer than 2 inches (50.8

mm) below the resistor.

(2) Still air: In still air, resistors shall be mounted with no circulation of air other than that created by the heat

of the resistors being operated.

b. Procedure: DC resistance shall be measured as specified in 4.6.2. Following this measurement, a potential

of 2.5 times the rated continuous working voltage but not to exceed twice the maximum voltage (see 3.1) shall

be applied for 5 seconds to the resistor terminals. Thirty minutes +5 minutes, -0 minutes after removal of the

test potential, the dc resistance shall again be measured as specified in 4.6.2.

4.6.6 Terminal strength (see 3.11). Resistors shall be tested in accordance with method 211 of MIL-STD-202.

The following details and exceptions shall apply:

4.6.6.1 Pull test (see 3.11.1). The following details shall apply:

a. Test condition letter: A

Apply load 5 pounds. Resistor shall be clamped by one terminal lead.

b. Initial measurement: DC resistance as specified in 4.6.2.

c. Examination after test: Resistors shall be examined for evidence of mechanical damage.

4.6.6.2 Twist test (see 3.11.2). After the test in 4.6.6.1, the following details shall apply:

a. Test condition letter: D.

b. Measurement after test: DC resistance shall be measured as specified in 4.6.2.

c. Examinations after test: Resistors shall be examined for evidence of breakage and other mechanical damage.

4.6.7 Dielectric withstanding voltage (see 3.12).

4.6.7.1 Atmospheric pressure. Resistors shall be tested in accordance with method 301 of MIL-STD-202. The

following details and exceptions shall apply:

a. Special preparations: Resistors shall be clamped in the trough of a 90� metallic V-block of such size that the

body of the resistor does not extend beyond the extremities of the block. The resistor leads shall be

positioned so that the distance between the resistor leads and any point of the V-block is not less than the

radius of the resistor minus the radius of the lead wire.

b. Initial measurement: DC resistance shall be measured as specified in 4.6.2.

c. Magnitude of test voltage: See 3.1.