• IZK ... cable type
• IZS ... bus-bar type
• IZW ... with primary winding terminals

The parameters of the secondary winding were not passed for these transformers but only: transmissions, the type of the relay, and the section of the conductor and the maximum distances of the clamps of the relay from transformer.
 
Information for individual transformers was passed on sides 2; 3; 4 and 5 in technical data, guaranteeing protection class 5P and the Accuracy Limit Factor ALF=15. According to the PN-EN 60044-1 standards the admissible current error contains oneself in borders ± 1% with the rated burden and the rated current.
 
This assures the correct cooperation of the transformer with the relay in the protection system according to the diagram of No. 1 and No. 2


These arrangements are designed to the protection of motor before:

• overload,
• derating,
• the asymmetry of phase currents,
• the atrophy of phaze,
• excessive growth of the temperature.

This variant has this advantage that the designer does not have to wonder over the proper selection transformer with the relay, because the correct working of this arrangement was confirmed in laboratory tests.
 
Complex transformer and relays it is possible to buy in factory prices both in our Company as and in AREVA T&D.

Technical data:

Type/Technical data	Primary current
With primary winding
IZW 1; IZW 2	5 ÷ 300 A
cable type
IZK 1; IZK 2	50 ÷ 600 A
IZK 3	125 ÷ 1500 A
bus-bar type
IZS 1; IZS 2; IZS 3	150 ÷ 2000 A

The example of application for direct starting with utilization of the protections of the motors of the type MiCOM P210 (the version: 4-19,75 A , 230 V AC) or P211 (the version: 4-6 A , 230 V AC or 24-230 V AC/DC) cooperating with the transformers of the type IZK or IZS:
Diagram no. 1 
 
The example of application for starting with "delta-WYE" with utilization of the protections of the motors of the type MiCOM P210 (the version: 4-19,75 A , 230 V AC) or P211 (the version: 4-6 A , 230 V AC or 24-230 V AC/DC) cooperating with the transformers of the type IZK or IZS:
Diagram no. 2
 
2. Transformers to the power supply the every kind of protection relays:

• IZK ...U  cable type
• IZS ...U  bus-bar type 
• IZW ..U  with primary winding terminals

The transformers are made in definite powers, in the protection classes 5P and 10P with the Accuracy Limit Factor ALF=5; 10; 15.

Technical data:

Type/Technical data	Primary current	Rated power	Accuracy class
with primary winding
IZW 1U	5 ÷ 300 A	1 ÷ 5 VA	5P 15 ÷ 10P 15
IZW 2U	5 ÷ 300 A	3,5 ÷ 10 VA	5P 10 ÷ 10P 15
cable type
IZK 1U	75 ÷ 400 A	1 ÷ 15 VA	5P 5 ÷ 10P 15
IZK 2U	50 ÷ 600 A	1 ÷ 15 VA
IZK 3U	50 ÷ 1000 A	1 ÷ 15 VA
bus-bar type
IZS 1U	150 ÷ 250 A	1 ÷ 5 VA	5P 5 ÷ 10P 15
IZS 2U	100 ÷ 500 A	1 ÷ 7,5 VA
IZS 3U	400 ÷ 2000 A	1,25 ÷ 15 VA
IZS 30U	100 ÷ 1500 A	1 ÷ 20 VA
IZS 31U	100 ÷ 1500 A	1 ÷ 25 VA
IZS 4U	200 ÷ 1500 A	1 ÷ 20 VA