IEEE 111:2000 pdf download.IEEE Standard for Wide-Band (Greater Than 1 Decade) Transformers.
1.1 General
IEEE 111 pertains to electronics wide-hand transformers transmitting power within a wide hand of frequencies covering typically at least one decade in the frequency spectrum. It is not intended to apply to transformers optimized to operate within a narrow hand of frequencies. Transformers used in. or in conjunction with, wire line communication facilities serving power stations are excluded due to the special protection requirements involved. Provision is made for including data for use in the design of feedback amplifiers and control networks, or other circuits in which the knowledge of the transformer amplitude and phase- frequency response is needed by the system designer. These transformers are required to transform voltage within specified tolerances of amplitude and phase when operating between specified impedances. Guides to application and test procedures are included. The annexes within this standard contain certain precautions and recommended practices.
This standard also pertains to hybrid transformers, primarily used in the telecommunications industry. The hybrid transformer is a wide-hand transformer used in a manner which makes it part of a capacitance, resistance. and/or inductance network. and it must have characteristics which permit it to match the network for proper overall performance.
1.2 Typical types of transformers to which this standard applies
1.2.1 Audio frequency transformers
Audio frequency transformers may cover a limited frequency range such as that used n voice communications. or may cover a part or all of the frequencies from 5 Hz to 10000 Hz when used in high fidelity or similar amplifiers. Voltages or signals correspond directly to speech or music amplitude and phase variations within this range of frequencies. Performance characteristics one or more octaves beyond the specified range may be of interest and specified. Feedback and other windings or taps may be incorporated in the design. The mode or class of amplifier operation (i.e., Class A, B, AB, etc.) must be recognized and taken into consideration.
1.2.2 Transducer service transformers
Transducer service transformers are stepdown ratio transformers having one or more secondary windings with or without center taps. The load impedance may be permitted to vary with frequency or with other parameters, hut the transformer performance is generally based on a specific load impedance.
1.2.3 Random noise transformers
Random noise transformers are used in vibration machine applications. They are subject to random signals of varying amplitude and duration. Response may be expressed in terms of the frequency spectrum but the amplitude variation allowable over the relevant frequency range is much greater than for audio-frequency transformers because of the Gaussian distribution of random noise. Random noise transformers are often included in feedback loops. When included in such a loop, their amplitude and phase response is of interest and all of the problems listed in 9.3 must be solved in addition to producing a transformer capable of handling the amplitude of random noise.IEEE 111 pdf download.