29
Checking of the readiness for operation can be carried out
as follows:
a) Load-dependent functional test on the current-
dependent transformer:
1. The current-dependent relay must be activated at a
value of 70% of the instrument transformer's rated
current.
2. The air vane with micro-switch is used for the
corresponding annunciation/monitoring.
b) Check for unimpeded normal running of the fan and
listen for any unusual bearing noise. Remove any dirt on
the fan rotor.
c) Check the unimpeded function of the wind vane and
microswitch by starting the fan several times.
d) Observe the circuit diagram and carefully reconnect the
wiring on completion.
• With regard to the switching devices, their
separate instruction manual should be observed
(GCEA670650 P0102 Rev 01)
• Check all switchgear accessories and auxiliary facilities
• No external discharge may occur on the surface of the
equipment at operating voltage. This can, for example,
be detected by characteristic noises, a clearly
perceptible smell of ozone, or visible glowing in the dark
• If irregular conditions are detected, then corresponding
repair measures should be initiated
7.3 Servicing
If, on the occasion of an inspection in accordance with 7.2,
the necessity of cleaning measures has been established,
proceed as follows:
• Before cleaning, where required, the working area must
be switched off and secured against reconnection in
accordance with the "Safety Regulations" specified by
IEC or another appropriate national standard
• Cleaning the surface in general:
- Weakly adhering dry dust deposits with a soft dry cloth
- More strongly adhering grime with mildly alkaline
household cleanser or with ETHANOL F 25M
• Cleaning insulating surfaces and conductive
components:
- Minor pollution with ETHANOL F 25M
- Strongly adhering pollution with ETHANOL F 25M
• Wipe down after cleaning, using clean water, and
dry properly
• Should external discharges occur as a result of
condensation, application of a thin silicone film on the
surface concerned is often effective as a temporary
remedy. It is advisable to request advice from the ABB
after-sales service department on permanent solutions
to such unusual problems
• Check that the bolt connections at the contact points in
the jumper system and the earth connections are tight
using torque wrench
• Top up grease or regrease with Isoflex Topas NB 52
lubricant when lubrication is inadequate or missing,
• Observe the maintenance instructions in the manuals for
the individual devices
7.3.1 I
S
-limiter
TM
device
Tripping device
No particular servicing of the I
S
-limiter
TM
tripping device is
generally necessary. Should dust deposits be noted on the
equipment installed despite the enclosure after a long
period of service in a relatively dusty environment, it is
advisable to clean these carefully with a soft brush, so as to
prevent the creation of tracking paths.
As with every other protection system, the I
S
-limiter
TM
tripping device should also be checked for perfect function
at relatively long intervals (e.g. every 12 months).
In order to conduct such a test, the I
S
-limiter
TM
is to be
deactivated and the I
S
-limiter
TM
insert replaced by
appropriate test insert. The test insert contains a glow lamp
as an indicator, which must flash when a tripping pulse is
received. If this occurs, it demonstrates that the tripping
circuit including the wiring and pulse transformer is
functioning correctly.
Apart from the test insert, other test are carried out which
can be used to check the most important functions of the
tripping device. Further instructions on performance of
these tests can be found in the relevant instruction manuals
GCEA670650 P0102 Rev 01.
Customer specific test procedures must also be referred
where ever applicable.
I
S
-limiter
TM
inserts
The I
S
-limiter
TM
inserts should be stored in a dry place.
To Next Page
Loading...
