IG-267-EN versión 01; 07/04/2017
49
General Instructions
ekor
.rpa
Sensors
6.1.1. Functional characteristics of current sensors
The current sensors are toroidal-core current transformers
with a high transformation ratio and low rated burden.
These sensors are encapsulated in self-extinguishing
polyurethane resin.
Phase current toroidal transformers
Ratio
300/1 A
1000/1 A
2500/1 A
Metering range
Extd. 130 %
Extd. 130 %
Extd. 130 %
Metering class
0.5
0.5
0.2S
Low range metering
class
At 1 % of I
n
± 0.4 % in amplitude
and ± 85 min in phase
At 0.5 % of I
n
± 0.35 % in amplitude and
± 25 min in phase
At 0.5 % of I
n
at 12.5 A: ± 0.3 % in amplitude and
± 20 min in phase
Protection class
5P20
5P20
5P13
Burden
0.18 VA
0.2 VA
0.2 VA
Thermal current
31.5 kA – 3 s
31.5 kA – 3 s
31.5 kA – 3 s
Dynamic current
2.5 I
th
2.5 I
th
2.6 I
th
Frequency
50 – 60 Hz
50 – 60 Hz
50 – 60 Hz
Insulation
0.72/3 kV
0.72/3 kV
0.72/3 kV
External diameter
139 mm
139 mm
139 mm
Internal diameter
82 mm
82 mm
82 mm
Height
38 mm
38 mm
38 mm
Weight
1.350 kg
1.650 kg
1.225 kg
Polarity
S1 – blue, S2 – brown
S1–blue, S2–brown
S1–blue, S2–brown
Encapsulated
Self-extinguishing polyurethane
Self-extinguishing polyurethane
Self-extinguishing polyurethane
Thermal class
B (130 °C)
B (130 °C)
B (130 °C)
Reference standard
IEC 60044-1
IEC 60044-1
IEC 61869-2
Table 6.2.
Current sensors
Figure 6.2.
Phase toroidal transformer
These toroidal transformers are factory-installed in the
cubicle bushings, which significantly simplifies the on-site
assembly and connection. This means the installation
protection is operational once the MV cables are connected
to the cubicle. There are no sensor installation errors, due
to earthing grids, polarities, etc. since they are previously
installed and tested at the factory.
All the current sensors have integrated protection against
the opening of secondary circuits, which protects against
overvoltages.
Summary of Contents for ekor.rpa Series
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