IEEE 515:2004 pdf free download – IEEE Standard for the Testing,Design, Installation, and Maintenance of Electrical Resistance Heat Tracing for Industrial Applications
Samples shall be terminated according to the manufacturer ‘s specifications, such that a heating length of atleast 600 mm or representative surface heating device dimensions are provided. The aging temperature ofthe test shall be the maximum declared maintain temperature of the heating device. The samplies shall beconditioned, while energized, at the aging temperature for 120 h主24 h. The initial output of the samples isthen to be determined by one of the three methods given in 4.1.11, with the exceptions of sample length andnumber of test temperature points for the procedure in item c) in 4.1.11.For this case, the samples shall beevaluated at rated voltage and at the manufacturer’s stated reference temperature for the rated output. Theoutput shall be within the manufacturer”s stated output range.
The samples shall be attached to a fixture or suitable heat sink as described in item c) in 4.1.11 and insulatedaccordingly. The pipe or heat sink temperature shall be set to the specified aging temperature andmaintained with ± 3 C plus 1% of the temperature reading in degrees Celsius. Circulating fluid or externalheating may be used to raise the fixture to the aging temperature. The samples shall be operated at ratedvoltage.The power supply shall be attached to a l5 min cycle timer such that the samples are energized forl2 min and de-energized for 3 min.The samples shall be exposed to this conditioning for 32 weeks (5376 h).
For heating devices with an intermittent temperature exposure rating, the samples are exposed to the sameconditioning for 32 weeks, except for an 8 h excursion once each week. At the beginning of the 8 h, thesamples shall be disengaged from the cycle timer. The pipe or heat sink temperature shall be increased to atemperature equal to the manufacturer’s stated intermittent exposure temperature. The time allowed toincrease the temperature should be no greater than l h.After 7 h from the beginning of the excursion, thepipe or heat sink temperature shall be decreased back to the aging temperature, again allowing no more thani h for the operation. Where the intermittent temperature rating is based on the heating device beingenergized, then the heating device shall be continuously energized during this temperature excursion, exceptduring cool down back to the maximum maintain temperature. Where the intermittent temperature rating isbased on the heating device being de-energized, the exposure cycle is conducted in a de-energized condition.At the end of the 8 h excursion, the samples shall be reengaged to the cycle timer.The excursions shouldoccur on the same day each week.
At the end of the 32 weeks of operation at the continuous rated temperature, the output of the samples shallbe determined by the same procedure as utilized for the initial readings. The heating device samples shallmaintain a power level within plus 20% or minus 25% of the initial measured output.
4.1.6.2 Alternative test
The test apparatus shall consist of a metal platen(s) with the ability to change temperature within specifiedlevels. The platen(s) shall be sized to expose all parts of the heating device samples，which would beexposed under normal installation conditions to the temperature levels required by this procedure.The testapparatus shall insure that the heating device samples are in intimate contact with the platen. The testapparatus may be supplied with a sample mounting fixture. Offsets may be built into the fixture or platen(s)to accommodate end termination/power transition fittings/boots,if provided，where their size profileexceeds the heating device profile. The apparatus shall allow energizing of the heating device samples asrequired during the test procedure.