DC motor - Siemens, s.r.o.
DC motor - Siemens, s.r.o.
DC motor - Siemens, s.r.o.
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5.4 Special operating conditions<br />
Light-load operation<br />
Operation<br />
If a <strong>motor</strong> is operated permanently or for a lengthy period of time at approximately<br />
half rated current or less, high levels of brush wear or problems with the<br />
commutator may occur (cf. section headed "Faults").<br />
If it is intended to run the <strong>motor</strong> permanently in light-load operation, consultation<br />
with the manufacturer is recommended.<br />
Loading at standstill<br />
see also<br />
5.5 Stoppages<br />
When <strong>DC</strong> machines are at standstill, armature current may be applied for only a<br />
limited time so as to prevent damage to the commutator.<br />
The permissible current values and times for loading at standstill must be obtained<br />
from the manufacturer.<br />
[ID 561]<br />
Faults with the brushes [→ Page 5-6]<br />
Faults with the commutator [→ Page 5-7]<br />
Measures required for <strong>motor</strong>s at standstill but ready for operation<br />
Lengthy stoppages<br />
•= Keep the <strong>motor</strong> dry with the standstill heating.<br />
After longer periods of standstill and when starting up at very low ambient<br />
temperatures (≤ 0 °C), the interior of the <strong>motor</strong> should additionally be freed from<br />
ice and dried by heating the exciter winding with 30% of the rated field current<br />
without ventilation for at least 30 minutes. The built-in standstill heating alone is<br />
no longer sufficient for this.<br />
•= In the case of <strong>motor</strong>s with a water cooler, pay attention to the risk of corrosion<br />
and frost (cf. supplementary instructions).<br />
•= For longer periods where the <strong>motor</strong> is not being used, either energize the <strong>motor</strong><br />
regularly, approximately once a month, or at least spin the rotor.<br />
In standby operation (design with cylindrical roller bearings), damage to the<br />
bearings cannot be ruled out in the event of external vibrations acting on the <strong>motor</strong>.<br />
To clarify what remedial measures are suitable, consultation with the manufacturer<br />
is recommended.<br />
If the <strong>motor</strong> is not to be used for a lengthy period, suitable anti-corrosion,<br />
mothballing, packaging and drying measures must be taken.<br />
SIEMENS AG T61160347010001 (DMHO V9)<br />
Operating instructions 1GG6286-0NA4.-1VV1-Z 5-3
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