bus bar

I think you are asking how do you choose a bus bar rating equal to your load amps. yes?

Please look at the NUMEROUS threads on CR4 covering this subject.

The current rating of a bus bar will depend on the material used for bus bar , size and shape of the bus bar , temperature rise and short circuit rating . Temperature rise will depend on the configuration and orientation of the bus bars.Number of bus bars (single bus bar or multiple bars placed in parallel) creepage distance between two bus and clearance between the busbars.

Dear Abraham sir

please explain "creepage distance". what is its role?

Kind regards

gova

Chennai-India

Dear Sir,

It is the minumum distance between the Condutive portion and the non conduting surafce.

Best Regards,

N.Suresh

Dear gova1467

The creepage distance is the distance between two conductors at different potentials measured along the surface of the insulating support.

IS specification is available for the minimum value of the Clarence and Creepage distance.

Dear abraham sir

where this creepage distance applicable.please give example

How to measure creapage distance?what is the minimum distance we have to consider?

Thanks and regards

gova

Dear gova1467

Take the case of bus section of a LT Distribution board. The bus bars are fitted on insulators. There is 440 volts PD between two busbars . The separating distance of the insulator is the possible creeping clearance. For a better understanding please see the following link.

http://www.harkis.harting.com/WebHelp/EHan/WebHelp/GBHANKriechstrecken.htm

http://www.harkis.harting.com/WebHelp/EHan/WebHelp/GBHANKriechstrecken.htm

Dear abrahim sir,

Thank u veru much sir.Now I got it.

As per the link ,This is applicable when two or more busbars/live components installed on the same platform or insulators.

Is this applicable for power system components (ex. Single phase CT or PT) installed on individual phases and each phases are separated from one another?

Kind regards

gova

Dear Guest,

Normally Current rating of BUs bar depends upon the Grade / Purity of BUs bar.

Same size of bus bars but of disfferent grades have diferrent temperature rise / losses per Amp per Mtr. We select the bus bar size so that temperature rise of the bus bar at rated current shall be less then 30 deg. C in Indian conditions ( Max. Ambient of 50 deg. C). So, the PVC sleeving does not burn / carbonise. Also, joints do not over heated, providing continuoues un interrupted operations.