Table of Contents
Advertisement
10.
INSTALLATION AND MAINTENANCE
10.1
INSTALLATION
The relay should be installed in a clean, dry and dust-free place, with no vibrations. It should also be well lit to
facilitate inspection and testing.
Operational conditions as defined in section 5 must not be exceeded in any case.
The relay should be mounted on a vertical surface. Figure 3.2 shows the diagram for panel drilling for panel
mounting.
Given that the design of the MIF unit is based on high performance digital technology it is not necessary to recalibrate
the relay. However if the tests show that it is necessary to readjust the relay, it is recommended that the unit should
be returned to the manufacturer to have this done.
10.2
GROUND CONNECTION AND DISTURBANCES SUPPRESSION
Threaded plug labelled as GND
suppression circuits in the system work correctly. This connection should be as short as possible (preferably 25 cm or
less) to guarantee maximum protection. In this way the capacitors which are internally connected between the inputs
and ground divert high frequency disturbances directly to ground without passing through the electronic circuits, with
the result that the circuits are perfectly protected.
In addition this connection also guarantees the physical safety of the personnel who have to touch the relay, since the
whole casing is connected to ground.
10.3
MAINTENANCE
Given the important role that the protection relays play in the operation of any installation, a periodic program of tests
is highly recommended. The unit incorporates built-in diagnostic functions that permit immediate identification with
only the aid of the keypad and display, the detection of some of the most likely circuit failures. Testing the unit is
recommended at intervals of 2 years or more. Although the built-in diagnosis does not reduce the average time
between failures, it does increase the availability of the protection because it allows a drastic reduction in the average
interruption time involved in detecting and repairing the fail.
The set of tests that can be carried out to test that all the features of the MIF unit function properly is described in
detail in the chapter entitled COMMISSIONING.
10.4
CLEANING INSTRUCTIONS
In case of detecting accumulated pollution, the unit can be cleaned with a clean cloth dry or slightly dampened with a
cleaner containing alcohol.
Abrasive cleaners must be avoided, as these can damage the metallic surface or the electrical connection elements.
GEK-106273L
INSTALLATION AND MAINTENANCE
(refer to figure 3.5) should be connected to ground so that the disturbance
MIF Digital Feeder Protection
10-1
Advertisement
Table of Contents
