Table of Contents
Advertisement
s
When the check is over the whole aggregate can be launched according to operational instructions
designed for the whole set.
In case that the machine is not put out of operation for more than 3 months, only a visual inspection
(according by
Tab.
8) is sufficient before the connection starts.
4.4.2 Change of rotating direction
Change of rotating direction is possible only in generators equipped with a fan that can rotate in both
directions. Change of direction is performed by switching over the terminals k and l of current transformer
(Fig.
15). Change of rotating direction is accompanied with the change of phase sequence on the main
terminals. Rotating direction cannot be changed in generators that have got only one-way fan. The fan must
be exchanged.
4.4.3 Operation
! WARNING If any changes occur that are different from normal operation (higher input, temperature or
vibrations, unusual noise or smells, reaction of control devices etc.), it means that function is damaged.
Maintenance staff must be called immediately to prevent breakdowns that can directly or indirectly jeopardize
people or that can cause damage to property.
IN CASE OF ANY DOUBTS, IMMEDIATELY DISCONNECT APPROPRIATE DRIVING MECHANISM
Generator is able to be excited itself. But the following must be taken into consideration:
- Required terminal voltage in the extent of U
by external potentiometer after nominal revolutions are reached.
- Generator can be fully loaded after nominal speeds are reached
The following operational data must be checked again:
- Current, generator cannot be overloaded
- Symmetry of load of individual phases
- Frequency
- Increase of temperature in bearings, cooling of machine and mechanical operation
To prevent resonance, take heed of the following: own electromechanical frequencies of generator
must not be in accordance with mechanical exciting frequencies of driving machine.
4.4.4 Check of operation
The function of generator must be continuously observed during operation so as to avoid a breakdown.
Its course must be recorded in generator operational logbook, especially the changes that are unusual in
the course of normal operation. Any found imperfections must be repaired immediately. Above all,
generator must be clean, must be secured in accordance with the data on output name plate, running
must be centred without vibrations, perfect condition of bearings and good tightening of connection
terminals. During generator operation ventilation openings must not be covered in any way. If a generator
was out of operation for longer period, insulation resistance of winding, condition of lubrication in
bearings, tightening of terminal bolts and mechanical connection with driving machine must be inspected
prior to putting the machine into operation.
4.4.5 Intervals of preventive inspections
4.4.5.1
Preventive inspection I.
Is carried out regularly in the course of common operation of the machine after 500 and 5000 operational
hours from the beginning. The inspection consists of:
a) Inspection of cleanliness of cooling surfaces of machine.
b) Measurement of stator winding insulation resistance.
c) Inspection of bearings operation.
d) Inspection of function of additional equipment.
e) Measurement of rotor winding circuit insulation resistance.(rectifier have to be short-circuited –
all connectors of rectifier have to be connected, measuring voltage is 500V)
Any found imperfections must be repaired prior to putting the machine into operation.
Product documentation 1D 3.8.en
± 5% or according to technical specification can be set
N
Rev. E, 10/13
page 31/42
Advertisement
Table of Contents
