cybelec DNC 1200 Informations Techniques page 15

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Low voltage sensítíve
elements
~
.
.
Servo-ampli.
Transformers
switchíng power
supply
Power supply of the
numerícal control
A power servo-amp1i ís an ímportant source of
electromagnetíc ínterference.
Partícular attentíon should be taken for íts
connection and necessary protections.
They wí11 be placed as far as possible from the
sensítíve elements and "sensítíve" termínals.
Servo-amplís
Supply transformer
for the servo-amplis
The servo-amplífıer wí11 be covered by a metallíc
casíng whích acts as a Faraday cage.
By experience, ít ís recommended to place a
fılter oп the servo-amplifier power supply. The
filter and the power supply are placed as near as
possíble to the servo-amplifıers.
The connectíons of the motors to the servo-
amplífiers must be shielded.
The shíeld must cover the power cables, the
posítíon captor and the motors ínsíde the
electńcal cabínet up to the servo-amplífiers. The
power cables and the positíon captor must not be
interrupted.
The earthíng of the shíeld of these cables must be
done as near as possible to the servo-amplífier
(see further on Connection precautions, Basic
rules ).
If thesc measures prove ínsufficíent, ít wí]1 then
be necessary to place a filter at the servo-
amplífıer output.
Often in this case, the shíeld is no longer
necessary for the motor cables.
In the case of DC motors, the output filter
ímproves the motor capacíty and reduces overall
heatíng.
These elements should be placed as far as
possíble from the sensítíve zones.
The switchíng power supply wi11 comply wíth
the EMC standards.
In some countríes, the main power supply can be
subject to major varíatíons.
Such dísturbances can cause ínconveníences to
the numerícal control.
1n such cases ít ís recommended to install an
uninterruptíble power supply (UPS) on the
supply line of the DNC.
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