Detailed Product Description
Protective current transformers are required to operate over a range of current many times the circuit rating and is frequently subjected to conditions greatly exceeding those which it would be subjected to as a measuring current transformer.When a current transformer is used to energise a protective relay,it must maintain its characteristic ratio up to some multiple of its rated current.This multiple,may be 5,10,20 or some even higher value and is known as the Acuuracy Limit Factor(ALF).Therefore,the selection of Protective Transformers in relation to accuracy class and ALFrequrie a close examination of relay characteristic and circuit conditions which includes the relay burden and the pilot wire lead burden.
Primary current(A):30A-5000A
Secondary current:5A,1A
Class:1.0,3.0
Frequency:50-60HZ
Rated load:5VA-15VA
Standard approval:BS7626,IEC185
Shore-time thermal current:1th=60x1h
Rated security coefficient:Fs<5
SFIM current transformers comply with the highest international quality standards with professional experience in the industry.SFIM products have built a reputation for quality and modern design at competitive prices.
SFIM current transformers are made according to the IEC44-1,BS3938,and DIN 42600 standards.
Case:all cases are made of non-combustible plastic material according to UL-94VO.
Insulation class:E(120max)
Ambient temperature:-20+45(+65)
Storage temperature:-50+80
Test voltage:4Kveff 50HZ lmin
Operating frequency:50HZ/60HZ
Rated secondary current:5A or 1A
Rated burden:1VA,1.5VA,2.5VA,3.75VA,5VA,7.5VA,10VA,12.5VA.,15VA,20VA,30VA,45VA,60VA
Accuracy:0.5 for exact measuring.(for kwh measuring),1.0 for general measuring with switch board instruments,3.0 for other not so exact measuring.
Connection:the secondary connections are with two terminals(two terminals for each connection),use M4 or M5 screws to fix which can be handled easily and secure low contacted resistance.
Accessories:the terminal cover is executed to assure the lead seal.This execution complies with the VGB4 protection of DIN57106 standard.
This type current transformer is made according to BS3938 with ABS non-combustible plastic case.
