3
1. Service conditions
The transformers need to be installed in dry and in-
door conditions where the ambient air is not sig-
nificantly polluted by dust, smoke, corrosive gases,
vapours or salts. The transformers are designed
for standard ambient temperatures between -25°C
and +40°C (it depends on each type) and altitudes
below 1 000 m above sea level. The transformers
can also be operated at higher or lower ambient air
temperatures and higher installation altitudes if
such are agreed with the manufacturer.
2. Technical details
Technical details and specifications of each of the
transformers are shown on a rating plate fixed to
the transformer body. It is not allowed to operate
the transformer at values exceeding the name-
plate data. Dimensional drawings of KOKM trans-
formers are defined in the Catalogue. Dimensions
of the KOKM transformers are defined by the type
marking, see the example:
KOKM 1 D C 10
Transformers width
10 = 100 mm (possibility -
6, 8, 10, 12, 14, 16, 18, 20,
22, 24,...30)
Outer diameter
C = 148 mm
Hole diameter
D = 60 mm
Rate voltage 1 = 1.2 V
Type KOKM - indoor use
—
01
Where:
1VLT5115001983
serial number
KOKM 1EB8
type code of transformer
50 Hz
rated frequency
S1-S2
terminal marking
600/1A
rated transformer ratio
Ext.120%
ratio extension
5 VA
rated output (burden)
5P20
accuracy class
1/6 kV
highest voltage for equipment/
power-frequency withstand voltage
Ith: 25(3s)kA
rated short-time thermal current
and duration
IEC 61869-2
corresponding standard (standards)
Idyn: 62.5kA
rated dynamic current
DE-15-M-PTB-xxxx
metrological standard
2015
year of manufacture
E
Insulating temperature class
40 °C
Ambient temperature
—
01 Example of cable
current instrument
transformer rating plate
—
Instuctions for installation, use and
maintenance for cable current instrument
transformers
These instructions apply for cable current instrument transformers intented for
indoor operation, where primary insulation is provided by primary conductor and its
insulation. KOKM transformers are designed for U
sys
> 1 kV.
The instructions refer to the following types: KOKM 06, KOKM 072, KOKM 1
