1.1 Ambient temperature:-
Temperature surrounding the workpiece including the trace heater and any thermal insulation or weather barrier that may be applied.
1.1.1 Maximum ambient temperature:-
Highest specified ambient temperature.
1.1.2 Minimum ambient temperature:-
Lowest ambient temperature specified at which trace heating is operable and performs according to specified requirements (and on which heat-loss calculations are based).
1.2 Branch circuit:-
Portion of the wiring installation between the overcurrent device protecting the circuit and the trace heater unit(s).
1.3 Connections (terminations)
1.3.1 Cold lead:-
Electrically insulated conductor or conductors used to connect a trace heater to a branch circuit and designed so that it does not produce significant heat.
1.3.2 End termination:-
Termination, which may be heat producing, applied to a trace heater at the end opposite to that where the power is supplied.
1.3.3 Power termination:-
Termination applied to the end of a trace heater at which the power is supplied.
1.3.4 Tee:-
Electrical connection of trace heaters, in series or in parallel, to accommodate a branch or a branch circuit.
1.4 Controlled design:-
Design where the set point of the applicable temperature controller or high-limit device is used in establishing the maximum sheath temperature
1.5 Dead leg:-
Segment of process piping segregated from the normal flow pattern for the purpose of providing a heat loss reference.
1.6 Design loading:-
Minimum power that meets the design requirements, in the specified adverse conditions, after voltage and resistance tolerances and appropriate safety factors have been considered
1.7 Factory fabricated:-
Assembled into units or sets, including the necessary terminations and connections
1.8 Field assembled:-
Supplied in bulk with terminating components to be assembled at the work site
1.9 Heat loss:-
Energy flow from a pipe, vessel or equipment to its surroundings.
1.10 Maximum continuous exposure temperature (trace heater de-energized):-
Highest allowable continuous temperature to which the trace heating system may be exposed as declared by the manufacturer
1.11 Maximum maintain temperature / Maximum continuous operating temperature (trace heater energized):-
Specified maximum workpiece temperature the trace heater operates at continuously as declared by the manufacturer
1.12 Maximum intermittent exposure temperature (trace heater energized or de-energized):-
Highest allowable intermittent temperature to which a trace heater may be exposed, as declared by the manufacturer
1.13 Maintain temperature:-
Specified temperature of a workpiece or process that the trace heaters shall be able to maintain.
1.14 Maximum sheath temperature:-
Maximum temperature of the outermost covering of a trace heater
1.15 Maximum withstand temperature:-
Maximum operating or exposure temperature that will not adversely affect the thermal stability of the trace heater and its component parts
1.16 Minimum installation temperature:-
Minimum temperature at which the trace heating system may be handled and installed
1.17 Operating voltage:-
Actual voltage applied to the trace heater when in service.
