IG-183-EN version 06; 31/03/2020
38
Recommended sequence of operations
General instructions
cgm
.3 system: medium voltage SF
6
gas-insulated
cubicles up to 38 kV according to IEEE and CSA standards
5. Recommended sequence of operations
Before carrying out any operation when voltage
is present, check the SF
6
gas pressure, using the
manometer.
Do not operate if SF
6
pressure is low.
For safety reasons, maintenance operations performed
directly on the driving mechanism must be performed
WITHOUT any actuating lever inserted.
Do not refill the switchgear.
5.1. Checking voltage presence and phase balance
Any universal comparator which complies with
specifications of standard IEC 62271-206 can be used for
checking that the medium voltage cables are correctly
connected to the transformer substations feeder cubicles.
On demand,
Ormazabal
can supply the
ekor
.spc
phase comparator unit.
Firstly, connect the red cables of the
ekor
.spc unit to the
corresponding phase test points on the
ekor
.vpis units,
and the black cable to the ground test point. This operation
must be repeated for all the phases L1, L2 and L3.
See section “
1.1.1. Voltage presence indication unit”
of
this general instructions document.