ACB and VCB setting

[ikram shehzad]

Dear all,

                is ther any body who can tell me about the setting of ACB(air circuit breaker ). what kind of it,s setting is and how to do it,s setting. also please tell me the setting of VCB(vaccume circuit breaker) . please tell me their setting,s.

i will b very thank ful to all of u.

Thank,s and Regard,s.

Muhammed Ikram.

[Spir Georges GHALI]

ikram shehzad said:

Dear all,

                is ther any body who can tell me about the setting of ACB(air circuit breaker ). what kind of it,s setting is and how to do it,s setting. also please tell me the setting of VCB(vaccume circuit breaker) . please tell me their setting,s.

i will b very thank ful to all of u.

Thank,s and Regard,s.

Muhammed Ikram.

---

Dear Mr. Ikram ;

 

An ” ACB ” is a circuit breaker dedicated to protcet the Electrical Low Voltage Networks, that are equiped of many kind of protections noting that are all Electronic Protection installed in the ACB and internaly connected with ” Current Transformers ” that are also istalled in the ACB, these protections are :

– Thermal Protcetion against ” Overload faults ” : it can be adjusted ” Ir : 0.4   to   1 x In “, where ” In ” is the nominal current of ACB like : 2500A  or  3200A  or  4000A, so, if we adjusted it at ” 0.5 ” for ” ACB – 4000A “, the thermal protcetion value is ” Ir = 0.5 x 4000 = 2000A “

– Magnetic Protection for ” Short Circuit Faults ” : it can adjusted ” Isd : 1.5   to   10 x Ir ” or for some manufacters to ” 12 “, so, if we adjusted for the same ACB at ” 6 “, the magnetic protection value is ” Isd = 6 x 2000 = 12000A “.

– Earth Fault Protection against direct fault between any phase and the protection line, it can be adjusted ” Ig : 0.3   to   1 x In “, so, if we adjusted it for the same ACB at ” 0.7 “, the earth fault protection value is ” Ig = 0.7 x 4000 = 2800A “.

-Residual Protection against ” Residual Faults ” that means against indirect fault where the fault current's value is normaly small ( a few Amps ), it can asjusted ” IΔn : 0.5   to   30A “. 

– Instantaneous Protection against ” Short Circuit Faults ” when the fault's current value will be very big, and in the same time we want that ACB trip quickly without delaying, it can adjusted ” Ii : 2   to   15 x In ” and we can also switched-off, so, if we adjusted it for the same ACB at ” 6 ” the instantaneous protection value is ” Ii = 6 x 4000 = 24000A “.

In some ACB there's also a ” Timing Delay ” for the thermal protection and for the magnetic protection, where the ” Timimg delay ” for thermal protection can be adjusted is ” Seconds “, but the ” Timing Delay ” for the magnetic protection can be adhusted in ” mili-Seconds “, and we use these ” Timing Delay ” in ACB to realize the ” Discrimination  or  Selectivuty ” between 2 ACB's  or  between ACB and MCCB .

 

Regards

[ikram shehzad]

dear ghali,

              thank u very much for this important information. it is very use full.

again thank,s.

[Spir Georges GHALI]

ikram shehzad said:

Dear all,

                is ther any body who can tell me about the setting of ACB(air circuit breaker ). what kind of it,s setting is and how to do it,s setting. also please tell me the setting of VCB(vaccume circuit breaker) . please tell me their setting,s.

i will b very thank ful to all of u.

Thank,s and Regard,s.

Muhammed Ikram.

---

Dear Mr. Ikram ;

 

VCB :

They are Circuit Breakes, but the volume of tripping is done in a small empty room that means inside this room there's nothing, becuase in the standard circuit breakers the tripping is done in Air. This technology is using for MV circuit breakers and useed also from some companies for low voltage circuit breakers, and I thing for LV it's finiched.

 

Regards.

[ikram shehzad]

Dear ghali,

                a bundle of thank,s for this information. but i know the the the theory of VCB. just want to know it,s setting. as u tell me before this about ACB. it was very usefull.

Thank,s.

[Spir Georges GHALI]

ikram shehzad said:

Dear ghali,

                a bundle of thank,s for this information. but i know the the the theory of VCB. just want to know it,s setting. as u tell me before this about ACB. it was very usefull.

Thank,s.

---

Dear Mr. Ikram ;

 

Please let me know the type of VCB that you're talking about to give you an idea about the settings.

 

Regards.

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