Hubner TDP 0,7 Series, Руководство по сборке

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D.C. tachometer generator TDP 0,7
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BETR-TDP0,7-en_R5(2018-12-20)ID74716 .doc
3.3.3 General technical data
General Information
Magnetic system - external field influence
The magnetic system of this machine consists of two permanent block magnets made from an AINiCo
alloy specially developed for this machine. The direction of magnetisation is determined by the
preferred magnetic orientation.
To guarantee non-ageing operation the permanent magnets are artificially aged until they reach their
optimum remanent density of magnetic energy. Avoid short-circuits because of the unfavourable
effects on the commutator; any burnouts can lead to additional harmonics.
Magnetisation - external field influence
To prevent voltage loss ensure the magnetic circuit of the machine is not interrupted after
magnetising.
Insulation
Insulation class B
Voltage
The listed voltages are detailed in the technical tables. Intermediate values and special voltages
are optional (Option).
Speed / voltage characteristic
n rpm
Terminal connection - polarity
Connecting a two-pole terminal board. When operating the machine in a clockwise direction
(viewing the shaft end) the Ai terminal is positive and the AU terminal is negative.
Carbon brushes / brush holders
The dimensional design and quality of the silver-graphite carbon brushes guarantee a long service
life and maintenance-free operations. The service life of the carbon brushes depends to a large
extent on the condition of the circulating air and the peripheral speed. Under normal operating
conditions the service life is approx. 15 000 operating hours.
Suitable, solid double-type brush holders with increased brush pressure (600 cN/cm2) for DC tacho-
generators subjected to vibration and shock loads.
Temperature compensation
There is a reduction in voltage when the temperature increases as a consequence of the temperature
course of the permanent magnet as well as an increase in the internal resistance of the windings. It is
possible to compensate the temperature course of the permanent magnet to a tolerance of
±0.5% per 10 K in the temperature range 0 to +100 °C (Option).
.
Harmonics
A low percentage harmonic content (distortion) across a large speed range is a significant
characteristic of a good tacho voltage. The r.m.s. value of the overall mix of harmonics is generally
measured using a thermionic voltmeter and considered in relation to the DC voltage.
This value is approx. 3‰ at a speed between 100 to 3000 rpm.
Machine related harmonics result from the construction, electrical design and utilisation as well as
production asymmetries.
Assembly related harmonics (single and double speed frequency) are caused by angular
misalignment and parallel displacement.
Ensure precisely centred assembly, in particular in conjunction with B 3.
Align added device referring to a harmonics oscillogram (<5‰).
U, U
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