Connecting The Ground Conductor - Siemens 1PH728 Series Operating Instructions Manual

Installation / Assembly
Internal equipotential bonding
The equipotential bonding between the earth terminal in the terminal box housing
and the motor frame is established via the terminal box mounting bolts. The
contact points underneath the bolt heads are bare metal and are protected against
corrosion.
The standard terminal box cover mounting screws are adequate as potential
bonding between the terminal box cover and terminal box itself.
Note
Connecting points are provided on the enclosure or end shield to allow an outer PE
conductor or equipotential bonding conductor to be connected (see section entitled

"Connecting the ground conductor").

Final checks
Before closing the terminal box, please check that:
the electrical connections in the terminal box are tight and are in full
–
compliance with the specifications above.
the clearances of 10 mm required are complied with.
–
no wire ends are standing proud.
–
the inside of the terminal box is clean and free of any cable pieces.
–
all seals and sealing surfaces are not damaged.
–
the connecting cables are laid in an open arrangement and the cable
–
insulation cannot be damaged.
cable entries which are not used are sealed and the plugs are tightly
–
screwed-in (i.e. so that they can only be removed using the suitable tools).
the right cable glands are fitted with respect to the correct degree of
–
protection, method of laying, permissible cable diameter etc., as stated in the
specifications.
Then close the terminal box.
Note
Tightening torque for the fixing screws of the lid: 22 Nm
3.5 Connecting the ground conductor
General
The cross-section of the ground conductor of the motor must comply with the
regulations for electrical installations, e.g. IEC / EN 60204-1.
3-8
SIEMENS AG - Operating Instructions
Three-phase induction motor 1PH728.