3
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Instructions for installation, use and
maintenance for current and voltage
transformers
1. Service conditions
The transformers should be mounted in dry indoor
conditions where the ambient air is not signifi-
cantly polluted by dust, smoke, corrosive gases,
vapours or salt.
The transformers are designed for standard ambi-
ent temperature between –5°C and +40°C. The al-
titude for use should be lower than 1000 m above
the sea level. The transformers may be used also in
higher or lower ambient temperatures and higher
altitudes when agreed between the manufacturer
and purchaser.
2. Technical details
The technical details for each individual trans-
former are mentioned on the rating plate fastened
on the transformer. Values mentioned on the rat-
ing plate must not be exceeded. Markings used on
the rating plate are as follows:
Where:
serial number + barcode
transformer type code
order number
rated frequency
first tap
second tap
accuracy classes
rated output
ext extension
Icth rated thermal current
Ith rated short time thermal current
ambient temperature
Idyn rated dynamic current
E temperature class
year of production
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01
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01 Example of current
transformer label
This installation, use and maintenance
guide is valid for current and voltage
transformers operating in indoor
conditions.
These instructions are valid for
Current transformer type:
Voltage transformers types: