IEEE Std 515 pdf free download

IEEE Std 515 pdf free download.Testing, Design, Installation, and Maintenance of Electrical Resistance Trace Heating for Industrial Applications.
4.1.5 Thermal stability of electrical insulating material
A sample of the trace heater shall be placed in a forced-circulation air oven. The oven shall be heated to, and maintained fbr a period of four weeks at a temperature of 20 °C above the maximum withstand temperature declared by the manufacturer.
The sample shall he removed from the air oven and cooled to room temperature. Trace heater samples shall be wound six close turns around a mandrel having a radius equal to six times the diameter or six times the thickness of the trace heater. Integral components and trace heater panels shall not be wound around the mandrel. Trace heater pads shall be wrapped on a mandrel with a radius equivalent to the manufacturer’s minimum recommended bending radius. While still on the mandrel, the sample. except at terminations or ends where the conductor is exposed, shall be submerged in tap water for 5 mm. While still in the tap water, the dielectric test 4.1.1 and the insulation resistance test 4.1.2 shall be conducted. Upon completion of the test, the sample shall have no visible cracks when examined with normal vision.
Terminations that improve the vapor tightness ofMI trace heaters with electrical insulation that is a hygroscopic material (for example, the cold end seals) are subjected to a temperature of 80 ± 2 °C for 4 weeks at not less than 90% relative humidity (R.H.). Compliance of the sample or prototype shall be verified by testing the electrical insulation in accordance with 4.1.1 and 4.1.2.
4.1.6 Thermal performance test
It is critical that the maximum sheath temperature of a trace heater is lower than the maximum ratings of the trace heater materials. This test demonstrates the thermal safety by verifying the power output stability for all parallel trace heater products with respect to time.
The test apparatus shall consist of a heated metal platen maintained at the specified high test temperature and a coolcd metal platen maintained at the specified low test temperature with the test samples being alternated between the platens, or the test shall consist of a metal platen with built in heating and cooling capability to change the temperature within the specified levels. The apparatus is intended to be located in a room temperature environment. The platen(s) shall be sized to expose all parts of the trace heater samples, which would be exposed under normal installation conditions, to the temperature levels required by this procedure. The test apparatus shall verify that the trace heater samples are in intimate contact with the platen. The test apparatus 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 profile exceeds the trace heater profile. The apparatus shall allow energizing of the trace heater samples as required during the test procedure.
The samples shall be thermally insulated on the side not facing the platen so as to improve effective heat transfer from the platen to the trace heater samples.
The temperature of the platen(s) shall be uniformly controlled to a maximum tolerance of ±5 °C for platen temperatures less than I 00 0Q or 5% of the maximum continuous operating temperature if above 100 0Q•
The platen described above may be a flat metal plate, a metal pipe, or a metal surface typical of the majority of applications for the trace heater being tested.
The trace heater samples shall be within the upper half of the manufacturer’s declared thermal output tolerance, as determined by 4.1.11 b). For trace heaters that are irregular in shape, and for surface heaters, the sample shall consist of at least one heating unit.IEEE Std 515 pdf download.