7
Siemens AG
ENGLISH
If the motor is
supplied by means of converters
, high-frequency
current and voltage harmonics in the motor supply leads can cause
electromagnetic interference to be emitted. Screened supply leads
are therefore recommended.
The following checks must be carried out prior to start-up:
- The rotor must be able to turn freely,
- The motor must be properly assembled and aligned,
- The output elements must be set correctly (e.g. belt tension of belt
drive) and be suitable for the intended field service conditions,
- All the electrical connections, the fixing screws and the connecting
elements must be designed and tightened in accordance with the
specified values,
- The PE conductor must be properly connected,
- Any supplementary devices (e.g. a brake) must be operational,
- Protection must be provided against electric shock for moving and
live parts,
- The cooling water is already circulating at the specified flow rate,
- The limit speed n
max
(see rating plate) must not be exceeded,
NOTE:
The limit speed n
max
is the maximum permissible peak
operating speed. It should be noted that the noise characteristics and
vibration response of the motor deteriorate as a result and that the
bearing replacement intervals are shortened.
The holding brake (if any) must be
checked after the motors have been
mounted, to ensure that it is
functioning correctly!
The holding brake is only designed for a limited number of
emergency braking operations.
It is not allowed to be used as a working brake.
This list of instructions makes no claims to completeness.
Other checks may also be necessary under certain
circumstances!
3
Repair
Safety precautions
The motor must be isolated in
accordance with standards prior to
carrying out any work on the system,
and especially before opening the covers of the core-and-
winding assemblies. Any auxiliary circuits must be isolated
in addition to the main circuits.
The usual "5 rules of safety" apply, e.g. as set out in DIN
VDE 0105:
- Isolate,
- Prevent from restarting,
- Verify isolation from supply,
- Earth and short-circuit,
- Cover or safeguard any neighbouring live parts.
These measures must not be reversed until all the repair
work has been completed and the motor fully assembled.
3.1
Temperature sensor
If the temperature sensor fails, it is possible to switch over to the
second (redundant ) temperature sensor by reversing the connections
in the terminal box.
Note the circuit diagram inside the terminal box!
3.2
Disassembly/assembly of the encoders
Caution! Encoder systems containing integrated
electronics (optical encoders, rotor position
encoders, gear wheel encoders, etc.) are
electrostatically sensitive components (ESDs).
The following rules must be observed when
working on ESDs:
- The place of work must be earthed,
- The connector pins must not be touched directly,
- No electrostatic charge must be transferred on contact (a
conductive object should be touched immediately before such
contact is made, for example),
- Suitable packaging must be used for transport (corrugated
cardboard boxes, conductive plastic bags -
not
ordinary plastic
bags, polystyrene, etc.).
Instructions for disassembling/assembling the encoders
- Remove/fit the cover,
- If necessary, secure a concentricity dial gauge to the encoder
casing and check whether the radial runout is less than the value
specified in the diagram (ROD431.001 / ERN 1381- Fig. 2) when the
rotor of the motor is turned one revolution. If this value is exceeded,
disassemble the encoder system again, clean the tapered surfaces
and reassemble the system, making sure it is properly aligned,
3.2.1 Disassembly/assembly of ERN1381 and
ROD 431.001
(8.50 - Fig. 2 and Fig. 3.1)
Disassembly
- Undo the screw
1
in the encoder and remove the cover,
- Remove the connector with the signal connector lead,
- Undo the screws (8.57) and the screw (8.51); the motor rotor must
be prevented from turning at the same time,
- Fit a grub screw (see Fig. 3.2), into the end of the shaft to protect the
centring bore and force off the encoder by inserting a screw .
Assembly
- Screw the torque arm (8.52) to the encoder with the screws (8.53)
(leaving a sufficient distance between the torque arm and the
encoder) and lock the screws, e.g. with Loctite 243,
- Position the encoder and the assembled torque arm on the taper of
the motor rotor and insert the screw (8.51); the motor rotor must be
prevented from turning at the same time. Note the maximum tightening
torque,
- Fasten the torque arm with the screws (8.57) and note the radial
runout on the encoder,
- Press the metal sleeve on the signal connector lead into the cover
- Plug in the connector with the word „TOP“ or nose facing inwards,
- Screw on the cover.
3.3
Changing bearings, lubrication
3.3.1 Bearing replacement intervals
NOTE:
Motor bearing types are subdivided into double D-end bearings,
and single D-end bearings driven motors!
75 % of the limit speed n
max
(see rating plate) must not be exceeded
during continuous operation.
Under normal operating conditions
, the replacement intervals t
LW
specified in Fig. 9 are recommended for the bearings of the 1PH4
motors.
The specified operating hours apply to a horizontal position, a coolant
temperature of +20 °C, a bearing temperature of +85 °C and vibrations
in accordance with vibration severity grade R (DIN VDE 530 Part 14).
The mean operating speed n
m
must be estimated if the motor speed
varies.
Under abnormal conditions
, e.g. a vertical position, operating
speed mostly above 75 % of the limit speed n
max
, severe vibration and
impact loads, frequent reversing, etc., the bearing replacement
intervals t
LW
must be reduced by up to 50 %.
