MIL-R-93 Resistors, Fixed, Wire-Wound, Accurate, General Specification ForThis specification covers the general requirements for accurate, wire-wound, fixed resistors having a maximum resistance tolerance of 1 percent, with the winding protected against high humidity. The resistors are rated for continuous full load operation at any ambient temperature up to 125 Degrees C, and derated up to 145 Degrees C. They are not capable for application where alternating current ac characteristics are of critical importance. Performance characteristics are in accordance with table I.

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MIL-R-93F

4.3.2 Precautions. Adequate precautions shall be taken during inspection to prevent condensation of moisture on resistors except during the moisture resistance temperature cycling test. Precautions shall also be taken to prevent damage by heat when soldering resistor leads to terminals.

4.4 Qualification inspection. Qualification inspection shall be performed at a laboratory acceptable to the Government (see 6.3).

4.4.1 Sample. The number of sample units comprising a sample of resistors to be submitted for qualification inspection shall be as specified in the appendix A to this specification.

4.4.2 Test routine. Sample units shall be subjected to the qualification inspection specified in table VII, in the order shown. All coated or enclosed sample units with exception of group IA samples shall be subjected to the inspection of group I. The remaining 24 coated or enclosed sample units shall then be divided as specified in table A-I, for groups II to V, inclusive and subjected to the inspection for their particular group. The 2 uncoated or unenclosed sample units shall be subjected to the visual and mechanical examination of group VII only.

4.4.3 Failures. Failures in excess of those allowed in table VII shall be cause for refusal to grant qualification.

4.5 Retention of qualification. Every 12 months, the manufacturer shall verify the retention of qualification to the qualifying activity. In addition, the manufacturer shall immediately notify the qualifying activity whenever the group B inspection results indicate failure of the qualified product to meet the requirements of this specification. Verification shall be based on meeting the following requirements:

a. The manufacturer has not modified the design of the item.

b. The specification requirements for the item have not been amended so far as to affect the character of the item.

c. Lot rejection for group A inspection does not exceed the group A sampling. d. The requirements for group B inspection are met.

When group B requirements were not met and the manufacturer has taken corrective action satisfactory to the Government, group B retesting shall be instituted.