Hubner TDP 0,7 Series, Assembly Instructions Manual

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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
Linearity
The suitability of a tacho-generator for widely varying control tasks is determined by the linear
relationship between the output voltage and speed.
Optimum load current and armature reaction
The max. permissible load current for the respective machine type is detailed in the table, which with
the linearity error should not be exceeded.
Linearity error values can reach 5‰ if the tacho-generator is operated at max. current loads. For very
precise control tasks of applications requiring a speed deviation range of 1‰ it is recommended to
choose the value detailed in the table for optimum load resistance as terminal resistance. These
relatively high ohmic terminal resistances ensure that just 1/10 of the maximum current is allowed to
flow. As a consequence, the armature reaction, which acts as the flux-weakening component when
higher currents flow, will be weakened by a factor of 10. This in turn means there will be no noticeable
field distortion resulting from armature reaction.
Brush contact voltage
DC tacho-generators are generally fitted with silver-graphite carbon brushes, which exhibit a very low
brush contact voltage. The total voltage drop at the sliding contact of the carbon brush/commutator
depends on the peripheral speed, current density below the brushes, brush pressure and the
characteristic build-up of patina on the brush contact surface.
Degree of protection to DIN VDE 0530 Part 5
This machine is designed to degree of protection IP 55, is completely enclosed and protected against
low pressure jets of water from all directions and the build-up of harmful deposits of dust.
Special degree of protection IP 56 when the shaft is sealed with an axial sealing ring (extra
charge). Max. speed 4000 rpm.
Shaft ends - shaft seals
The cylindrical shaft ends with Ø11 are machined with a closed keyway to DIN 6885 Blatt 1 (key
included in scope of supply). Special shafts with Ø7 and Ø6 available.
It is possible to seal all tacho-generators with a sealing ring on the drive side ; this is generally fitted
when adding a speed increasing gear.
Bearings
All designs are equipped with sealed and lubricated for life deep groove ball bearings.
Design Fixed bearing DS (drive side)
B 3, B 5 6201 LLU
Coating - surface protection
Light-grey coating RAL 7030.
In addition to special insulation an appropriate protective coating is applied to tacho-generators
exposed to aggressive gases and vapours.
Accessories
To maintain the degree of protection class rating IP 55 and IP 56 we use skin-tight cable glands
SR-1109 Pg 11 for connection cables Ø 7.5-9 mm.