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High Voltage Instrument Transformers | DDB/DFK/DDN/DFN
User manual
INTRODUCTION
FOREWORD/
This manual describes the construction, installation, commissioning and monitoring for safe use of a high-voltage instrument
transformer insulated by oil-paper.
SCOPE OF APPLICATION/
The manual applies to the following transformers:
› Capacitive Voltage Transformers, DDB Series, Models: DDB-72..170.
› Capacitive Voltage Transformers, DFK Series, Models: DFK-245..765.
› Coupling Capacitors, DDN Series, Models DDN-72..170.
› Coupling Capacitors, DFN Series, Models DFN-245..vvz765.
DESIGN/
Capacitive voltage transformers consist of 1 or more capacitor
units mounted on a tank containing the electromagnetic unit
(intermediate transformer, compensation reactance and
auxiliary elements).
The tank is fi tted with a box containing the secondary terminals
and the adjustment compensations (they are protected by a
sealed cover).
Oil volume variations in the capacitor unit(s) are compensated for
in one or more metal diaphragms located at the top of each unit.
In the inductive part (tank), the oil level is displayed by a direct
indicator. Each insulator is hermetically sealed and independent.
The coupling capacitors have the same characteristics as
previously indicated for capacitive voltage transformers but
without the electromagnetic unit (EMU).
1.
Primary terminal
2.
Oil volume compensating system
3.
Insulator
4.
Capacitors
5.
Intermediate voltage tap
6.
Inductive voltage transformer
7.
Secondary terminal box
8.
Upper Capacitor Unit
9.
Intermediate Capacitor Unit
10.
Lower Capacitor unit
11.
Electromagnetic Unit (EMU)
12.
Carrier accessories (on demand)
1
3
5
6
7
2
2
3
4
4
8
10
9
11
12