Ormazabal velatia transforma.earth, Общее руководство по инструкции

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Description and general features General instructions
transforma .earth
IG-286-EN version 01
1 DESCRIPTION AND GENERAL FEATURES
1.1 Design, manufacture, and testing
The earthing transformers manufactured by Ormazabal have
been designed and manufactured to meet mandatory standards
and testing regulations according to Medium Voltage (MV)
Electrotechnical Regulations in force at the time of its
manufacture, as well as specific customer specifications.
1 Expansion tank 9 Connection box
2 Oil level 10 Silica gel dehydrator
3 MV neutral terminal 11 Buchholz relay
4 MV phase terminals 12 Thermometer
5 Overpressure valve 13 Core and flange terminals
6 Upper filtering valve 14 Vacuum and lower filtering valve
7 Autovalves 15 Sampling valves
8 Current transformers connection boxes
Fig. 1.1: Detail of the transforma .earth components
1.1.1 Standard or routine testing
Earthing transformers are subjected to routine testing that
guarantees compliance with the following standards:
►
Measurement of winding resistance:
IEC
60076-1
►
Measurement of current vacuum loss:
IEC 60076-1
►
Measurement of earthing fault impedance:
IEC 60076-1
►
Electrical voltage applied at a power frequency test:
IEC
60076-3
►
Induced electrical voltage test:
IEC 60076-3
If the earthing transformer has a secondary function as an
auxiliary services transformer, the following routine tests are
also performed:
►
Measurement of the transformation relation and
verification of the connection group.
IEC 60076-1
►
Measurement of the short circuit impedance and load
loss IEC 60076-1
►
Voltage applied to auxiliary winding test
IEC 60076-3
For other standards, consult Ormazabal .
1.1.2 Testing protocol
All information related to testing to which the earthing
transformer has been submitted to is covered
in the "Testing Protocol", that accompanies the
documentation supplied together with the same.