Installation
Manual Single Power Unit BUM64S/A/F
Document no.: 5.01056.03
55
6
h
do not arrange net filters of the same type in series - the damping characteristics are
not improved.
h
for each unit use a separate mains filter. If you must suppress all drives together - do
not interrupt the screening between the converter and the motor. This means that
screened cables must not be interrupted by fuses, circuit breakers and other.
6.7.2.2 Grounding
To meet EMC requirements, the classical star grounding is no longer sufficient to reduce
the disturbance of high frequencies caused by converter operation. Better results can be
achieved by a reference surface which must be linked to the unit’s ground (e.g. bare metal
mounting plate and housing parts).
h
to avoid earth loops, position all ground conductors and screens as close as possible
to ground.
h
if it is possible to ground the controller reference potential of unit, form the connection
with as large a cross-section as possible and short (< 30 cm) cable (if it is possible to
ground the controller reference potential).
h
remove insulating layers such as paint, adhesives etc. from the ground connections.
h
if necessary, use serrated lock washers (DIN 6798) or similar measures to ensure a
permanent, conductive contact.
h
to prevent corrosion on ground connections, use suitable metal combinations (in the
sense of the electrochemical series of metals).
h
keep conductive electrolytes away from the connection by the use of protective coating
(e.g. with grease).
h
connect screens at both ends over a large contact surface and with good conductivity.
Only this way you can suppress the effects of magnetic or high frequency disturbance.
h
if earth loops occur (e.g. double insulation of the setpoint conductor screen), apply the
receiver side galvanically and the sender side capacitively.
h
when routing external cable screens through panels separating different EMC areas,
ensure contact of the panels to the cable screens.
figure 19: contacting cable screens when routing through cabinet panels
Cables which are passed through the panels of screening housings without special mea-
sures (e.g. filtering), may impair the screening effect of these housings.
Summary of Contents for BUM64A
Page 1: ...E 5 01056 03 Manual Single Power Unit BUM64S A F ...
Page 119: ......
