General Description; Service Conditions - ABB TDO 6 Instructions For Installation, Use And Maintenance Manual

1. General description

The voltage transformers are designed to supply measurement
and protection circuits in high voltage power networks (with
admissible voltage up to 40.5 kV and frequency 50 Hz or 60 Hz).
The instruction includes the following types of voltage
transformers:
– TJO 6, TJO 7, VOG-24– voltage transformers single-pole,
– TDO 6, VOL-24, VOL-40.5 – voltage transformers double-pole.
Design versions may differ depending on:
– dimensions,
– rated primary voltage (insulation level),
– secondary voltage,
– rated power in given accuracy class,
– thermal burden.
Examples of voltage transformers design (TDO 6, TJO 7 type) are
shown in the Figure No. 1 and 2.
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4
6
7
Figure 1. An example of the construction of a double-pole transformer
(based on transformer TDO 6)
4 Instruction manual
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1
2
3
7

2. Service conditions

The voltage transformers should be mounted in outdoor
conditions where the ambient air may be polluted by dust, smoke,
corrosive cases, vapours or salt. The voltage transformers are
designed for standard ambient temperature between -40°C and
+40°C and altitude lower than 1000 m above the sea level. The
average value of the ambient temperature, measured over a
period of 24 hours, should not exceed 35°C.
The transformers may be used also in higher or lower ambient
temperatures and higher altitudes when agreed between the
manufacturer and purchaser.
1 – Primary winding,
2 – Secondary Winding,
3 – Magnetic core,
4 – Epoxy resin housing, insulation
5 – Terminal primary winding,
6 – Terminal box of the terminals secondary windings,
7 – Steel baseplate with earthing terminal
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6
7
Figure 2. An example of the construction of a single-pole transformer
(based on transformer TJO 7)
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1
2
3