Current transformers support type ТОЛ-20 (TOL-20)

Current transformers support type ТОЛ-20 (TOL-20)

Current transformer TOL-20Description

Transformers are intended for transmitting of measuring information signal to measuring instruments and protection and control devices, for insulation of secondary alternating current circuits from high voltage in factory assembled switchgears on indoor and outdoor type on voltage class up to 20 kV of 50 or 60 Hz frequency. Transformers are manufactured in climatic version "УХЛ" (outdoor mounting) location category 2.

Features:

  • primary currents from 5 up to 2500 A;
  • accuracy classes of measuring windings: 0.2, 0.2S, 0.5,0.5S;
  • number of secondary windings 2, 3 or 4;
  • separate sealing of secondary windings;
  • insulation is from epoxy compound poured on in vacuum;
  • insulation level "b";
  • transformers have two length dimensions: 295 and 350 mm;
  • can be manufactured mounted on steel plate;
  • uniform mounting and connection dimensions for all design versions;
  • insulating barriers allow to decrease the distance between phases (on condition that bus-bars outside transformer are insulated). 

Table 1. Technical data

Parameter

Value of a given design 

TOL-20-2
TOL-20-3
TOL-20-4

TOL-20-2 VV
TOL-20-3 VV

TOL-20-2 VV-1
TOL-20-3 VV-1
TOL-20-4 VV-1

TOL-20-2 VV-1
TOL-20-3 VV-1

Rated voltage, kV

20 or 24

Maximum operating voltage, kV

24 or 26,5

Rated AC frequency, Hz

50 or 60

Rated primary current, A

5; 10; 15; 20; 30; 40; 50; 75; 80; 100; 150; 200; 300; 400; 600; 750; 800; 1000; 1200; 1500; 2000; 2500

2500

2500; 3000

4000

Rated secondary current, A

1; 5

Number of secondary windings

2,3,4

2,3

2,3,4

2,3

Accuracy class of a winding:

for measurement
for protection



0,2S; 0,2; 0,5S; 0,5; 1; 3
5Р; 10Р

Rated secondary burden, VA, of secondary winding:

for measurement

at cos φ = 1
at cos φ = 0,8 (inductive-active load)

for protection

at cos φ = 0,8 (inductive-active load)

 

 

1; 2; 2,5
3; 5; 10; 15; 20; 25; 30; 50



3; 5; 10; 15; 20; 25; 30; 50

Short-circuit current ratio of winding for protection**, at least

10

Instrument security factor of secondary winding for measurement***, no more than, in a given accuracy class at a given primary current:

 

0,2S; 0,2; 0,5S

5 - 2500

10

-

0,5

5 - 800

17

-

1000 - 2500

15

-

0,2S

2500; 3000; 4000

-

10

0,2; 0,5S; 0,5

-

21

Table 1 (continuation)

Parameter

Value of a given design

 TOL-20-2
TOL-20-3
TOL-20-4

 TOL-20-2 VV
TOL-20-3 VV

 TOL-20-2 VV-1
TOL-20-3 VV-1
TOL-20-4 VV-1

 TOL-20-2 VV-1
TOL-20-3 VV-1

One-second thermal current, kA, at a given primary current, A:

5
10
15
20
30
40
50
75
80
100
150
200
300; 400
600 - 2000
2500
3000
4000

 


0,40
0,78
1,20
1,56
2,50
3,00
5,00
5,85
6,23
10,00
12,50
20,00
31,50
40,00
61,00
-
-

 















-
61,00
61,00
-

 

















-
61,00

Dynamic current, kA, at a given primary current,A:

5
10
15
20
30
40
50
75
80
100
150
200
300; 400
600 - 2000
2500
3000
4000

 


1,00
1,97
3,00
3,93
6,25
7,56
12,80
14,70
15,70
25,50
31,80
51,00
81,00
102,00
152,50
-
-

 















-
152,50
152,50
-

 

















-
152,50

Notes to table 1:
1 ** Value is given for a rated secondary burden of 20 VA.
2 *** Value is given for a rated secondary burden of 10 VA.
3 Number of secondary windings, their types, accuracy classes, values of rated secondary burdens, rated cendary current, short-circuit current ratio and instrument security factor should be clearly specified in the order.

Table 3. Dimensions of transformers TOL-20-2 (3)VV and TOL-20-2 (3;4) VV-1

Transformer type Rated prmary current, A Pic. Dimensions, mm Weight, kg
A A1 B B1 h1 H H1 d S
TOL-20-2(3)VV 2500 5 32 32 80 178 73 300 347 14 16 35
TOL-20-2 (3;4) VV-1 6 265 67 20 50
3000 40 50 100 90 305 370 18 24 54

General view of transformer (drawing) pics. 1, 2, 3 and 4

General view of transformer (drawing) pics. 5 and 6