Recommended sequence of operations
27
General instructions
cgmcosmos
system
Medium voltage switchgear and control gear, fully insulated in SF
6
gas up to 24 kV with external cable test device
IG-257-EN version 01; 03/02/2016
5 Recommended sequence of operations
Before carrying out any operation when
voltage is present, we recommend checking
the SF
6
gas pressure, using the manometer.
5.1 Checking the gas pressure
Each tank has a manometer for checking the gas pressure,
which can easily be seen from outside the cubicle. The
manometer scale is divided into different colours: red,
grey and green. For safe operation, the needle must be
in the green zone of the corresponding temperature band.
Fig. 5.1
Gas pressure manometer
5.2 Voltage presence indicator
Ormazabal
has two options to indicate voltage presence:
•
The
ekor.
vpis
unit for indicating voltage presence,
designed in accordance with the standard
IEC 62271-206. Therefore, the “voltage presence”
indication is displayed when the phase-earth voltage
is equal to or greater than 45% of the rated voltage
and is not visible when the phase-earth voltage is less
than 10% of the rated voltage.
•
The
ekor.
ivds
unit for detecting voltage presence,
designed in accordance with the standard
IEC 61243-5. Therefore, the “voltage presence”
detection is given when the phase-earth voltage is
between 45% and 120% of the rated voltage and is
not visible when the phase-earth voltage is less than
10% of the rated voltage.
Both units provide a clear visual indication for the user,
without needing an auxiliary power supply for its operation.
For each of the three phases, the presence of voltage is
indicated by intermittent flashing of the indicators.
The voltage detection unit has the following displays:
1
L1, L2, L3
Display each of the indicator phases.
The numbering corresponds to the order of the
phases, from left to right, seen from the front of the
cubicle. Each phase has a test point for checking
the phase balance between cubicles.
2
Voltage presence indicator. A flashing light
indicates the presence of voltage in that phase.
3
Phase test points. Each phase has a test point for
checking the phase balance between cubicles.
4
Earth test point. This is only used for comparing
the phases.
Fig. 5.2
Voltage presence indication unit
Summary of Contents for cgmcosmos-2lv
Page 47: ......
