Downloaded from https://www.everyspec.com MIL-STD-810D 19”Ju1Y 1983 4.4.2 ~ci.lracvof.test ins rum entation calibratiou. The accuracy.of instruments and test equipment used to control or monitor the test parameters shall be verified prior to and following each teat and then calibrated in predetermined intervals and shall meet the requirements of MIL-STD-45662 to the satisfaction of the procuring activity. All instrument? and te?~ equipment used in conducting the teats specified herein ehall: a. Be calibrated to laboratory standards whose calibratioriis traceable to the National,Standards via primary standards, b.
Have an accuracy of at least one-third the tolerance for the variable to be measured. In the event of conflict between this accuracy and a require- ment for accuracy in any one of the test methods of this standard, the latter shall govern. 4.4.3 Stabilizat~ of test temuera~ 4.4.3.1 ~ item oDeratin~. Unless otherwise specified, temperature stabilization is attained when the temperature of the operating part of the test item considered to have the longest thermal lag ia changing no more than 2.00c (3.6oF) per hour. 4.4.3,.2,T~QQQoDe ratin~.
Unless otherwise specified, temperature stabilization is attained when the temperature of the operating‘partof the test item considered to have the longest thermal.lag reaches a temperature within test,tolerances of the nominal test temperature,except that any critical component (e.g., battery electrolyte for engine ‘startingtest) will be within 1° C (1.8° F). Structural or passive members are not normally considered for stabilization,purposesf When changing temperature, fOr”many teSt iteDIS,,.
the temperature of the chamber air may be adjusted beyond,the test cond+t.ion , lirnitato reduce stabilization time, provided the extended temperaturedoes.nOt induce response temperature in a critical component or area of the test item beyond the test temperature limits for tbe test item. ~.4.4 ~. Experience has shown definite advantages to performing certain tests immediate y before, in combination ,with,or immediately fOllOWing other tests, Where these advantages have been identified, guidance has been . put in I-3c of the test methods and shall be followed.
other sequences and combinations consistent with,1.2 and 4.2.1,of .GeneralRequirements may be used with the permission of the procuring agency. 4.4.5 ~. Guidance for choosing among the procedures of a method is found in section I of each ethod. 4.4.6 Test condl Ions .t. . Whenever practical, specific test levels, ranges, rates, and durations shall be derived from measurements made on actual or appropriately similar equipment (see 4.3). When specific measured data are not available, the test characteristics shall be tailored using tbe guidance found in section 5. ,., , 4.5 k! ~ 4.5.1 Jretest ‘uerformane r c ecord.
Before testing, the test item should be operated at standard ambient conditions (see 4.4) to obtain and record data for determining compliance with the requirements document(s) and for comparison 11 >