Connections For Different Starting Methods; Connections Of Auxiliaries; Terminals And Direction Of Rotation - ABB MT Série Manuel D'installation, D'exploitation Et De Maintenance

Minimum cross-sectional area of protective
conductors
Cross-sectional area of phase
conductors of the installation,
S, [mm ]
2
4
6
10
16
25
35
50
70
95
120
150
185
240
300
400
In addition, earthing or bonding connection facilities on
the outside of electrical apparatus must provide effective
connection of a conductor with a cross-sectional area of at
least 4 mm .
2
The cable connection between the network and motor
terminals must meet the requirements stated in the
national standards for installation or in the standard
IEC/EN 60204-1 according to the rated current indicated
on the rating plate.
NOTE!
When the ambient temperature exceeds +50 °C,
cables having permissible operating temperature
of +90 °C as minimum shall be used. Also all other
conversion factors depending on the installation
conditions shall be taken into account while sizing
the cables.
Ensure that the motor protection corresponds to the
environment and weather conditions. For example, make
sure that water cannot enter the motor or the terminal
boxes.
The seals of terminal boxes must be placed correctly in
the slots provided to ensure the correct IP class. A leak
could lead to penetration of dust or water, creating a risk of
flashover to live elements.
4.9.1 Connections for different starting
methods
The terminal box on standard single speed motors normally
contains six winding terminals and at least one earth
terminal. This enables the use of DOL- or Y/D –starting.
For two-speed and special motors, the supply connection
must follow the instructions inside the terminal box or in the
motor manual.
The voltage and connection are stamped on the rating
plate.
Standard_Manual_LV_Motors_ML_revF_Book.indb 9
Minimum cross-sectional area
of the corresponding protective
conductor, S , [mm ]
2
P
4
6
10
16
25
25
25
35
50
70
70
95
120
150
185
Low voltage motors manual, 3GZF500730-85 Rev F 02-2015 | ABB Motors and Generators 9
Direct-on-line starting (DOL):
Y or D winding connections may be used.
For example, 690 VY, 400 VD indicates Y-connection for
690 V and D-connection for 400 V.
Star/Delta (Wye/Delta) starting (Y/D):
The supply voltage must be equal to the rated voltage of
the motor when using a D-connection.
Remove all connection links from the terminal block.
Other starting methods and severe starting
conditions:
In cases where other starting methods e.g. converter or
soft starter will be used in the duty types of S1 and S2, it
is considered that the device is "isolated from the power
system when the electrical machine is running" as in the
standard IEC 60079-0 and thermal protection is optional.

4.9.2 Connections of auxiliaries

If a motor is equipped with thermistors or other RTDs
(Pt100, thermal relays, etc.) and auxiliary devices, it is
recommended they be used and connected by appropriate
means. For certain applications, it is mandatory to use
thermal protection. More detailed information can be found
in the documents delivered with the motor. Connection
diagrams for auxiliary elements and connection parts can
be found inside the terminal box.
The maximum measuring voltage for the thermistors is
2.5 V. The maximum measuring current for Pt100 is 5 mA.
Using a higher measuring voltage or current may cause
errors in readings or a damaged temperature detector.
The insulation of thermal sensors fulfills the requirements of
basic insulation.
4.10 Terminals and direction
of rotation
The shaft rotates clockwise when viewing the shaft face at
the motor drive end, and the line phase sequence - L1, L2,
L3 - is connected to the terminals as shown in figure 3.
To alter the direction of rotation, interchange any two
connections on the supply cables.
If the motor has a unidirectional fan, ensure that it rotates in
the same direction as the arrow marked on the motor.
6/2/2015 6:44:25 PM