Hubner TDP 1,2 Series, Operating And Assembly Instructions Manual

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D.C. tachometer generator TDP 1,2
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TDP1,2-MANUALen_R5(2018-12-19)ID74713 .doc
3.6
General technical data, electric implementation
Magnet system design
The magnet system of these machines consists of two permanent block magnets, developed especially
for these machines and manufactured in AINi Co alloy.
The direction of magnetization is determined by the material's optimum direction of magnetization. In
order to guarantee operation free of ageing problems, the permanent magnets are aged artificially until
they reach optimum remanent energy density.
CAUTION!
Short circuits should be avoided because of their bad effect on the commutator; any burn
marks can give rise to additional harmonics.
Magnetization, external effects
The machines are magnetised when mounted via an external power source.
The magnetising field strength required to saturate the permanent magnets is about 4000A / cm
CAUTION!
After magnetization, the machine's magnetic circuit must not be interrupted, otherwise a
voltage drop of approx. 25 % occurs. It is vital to follow precisely the dismantling
instructions of the machine (please ask for special leaflet, see page
32 ).
Any effect on the tacho voltage due to magnetic or electrical field stray is largely prevented by
strongly formed machine yoke.
Insulation
The standard insulation complies with Insulation Class B (VDE 0530). Special insulation types can
be provided to enable the tacho to operate in the following conditions:

Insulation Class F (ambient temperature to max. 100 °C). See temperature coefficient.

Humid and tropical condition

Limited resistance to acid and alkaline fumes Winding test: max. 1000 V on repeat test.