ABB MT Série Manuel D'installation, D'exploitation Et De Maintenance page 6

Connection
Normal machine design has the terminal box on top with
cable entry possible from both sides.
Some machines are available with top mounted terminal
boxes rotatable 4 x 90°, and some with side mounted
terminal boxes.
Availability of these solutions is described in the product
catalogues.
Unused cable entries must be closed.
As well as main winding and earthing terminals, the
terminal box can also contain connections for
thermistors, standstill heating elements, bimetallic,
switches, or PT 100 resistance elements.
WARNING
Voltage may be connected at standstill inside the
terminal box for heating elements or direct
winding heating.
Connection diagrams for auxiliary elements are found
inside the terminal box cover.
WARNING
The capacitor in single-phase motors can retain
a charge that appears across the motor terminals,
even when the motor has reached standstill.
Connection for variable speed drive
Variable speed drives cause higher voltage stresses
than the sinusoidal supply on the winding of the motor
and may cause high frequency shaft voltages and
bearing currents. Therefore the winding and the bearing
insulation of the motor as well as the filter at the con-
verter output must be dimensioned according to "Selec-
tion rules for VSD applications/Insulation" (3GZF500930-
2), available on request from ABB.
In variable speed drives the motor (Pn > 30 kW) must
be cabled by using shielded symmetrical cables and
cable glands providing 360° bonding (also called EMC
glands). More information can be found in ABB's manual
"Grounding and cabling of the drive system"
(3AFY61201998).
In frequency converter applications motor frame
external earthing must be used for equalising the
potential between the motor frame and the driven
machine, unless the two machines are mounted on the
same metallic base.
For motor frame sizes above IEC 280, use 0.75 x 70
mm flat conductor or at least two 50 mm² round conduc-
tors. The distance of the round conductors must be at
least 150 mm from each other.
6
This arrangement has no electrical safety function; the
purpose is to equalise the potentials. When the motor
and the gearbox are mounted on a common steel
fundament, no potential equalisation is required.
Potential equalisation
V1
U1
W1
PE
3 ~ M
0.75 mm
Driven machinery
To comply with EMC-requirements, use only cables and
connectors approved for this purpose. (See instruction
for frequency converters.)
The highest permissible rotational speed of a cast iron
motor used in variable speed drive (M2BA/M3BP) must
not exceed maximum permissible speeds as stated in
the figure below or the speed stamped on the rating
plate. For information on the highest permissible rota-
tional speed for other motor sizes and types, please
contact ABB. Bearing lubrication should follow the
directions mentioned later.
Frame Speed r/min
size 2 pole
280 3600
315 3600
355 3600
400 3600
If there is uncertainty concerning the suitability of the
motor for the variable speed drive, please contact ABB.
WARNING
The maximum operating temperature of the
grease and bearings must not be exceeded.
Balancing
The rotor of the machine is dynamically balanced.
As standard, balancing has been carried out using half
key, and the shaft is marked with a RED tape, with the
text "Balanced with half key".
To avoid vibration the coupling-half or pulley must be
balanced with half key after the keyway has been
machined.
In the event of balancing with full key the shaft is
marked with a YELLOW tape, with the text "Balanced
with full key".
In case balancing without key, the shaft is marked with
a BLUE tape, with the text "Balanced without key".
ABB / Low Voltage Motors / Manual 11-2002
Plate/strip
Cables/wires
> 150 mm
70 mm
2
min 50 mm
4 pole
2600
2300
2000
1800