Relay and Protection Coordination

Please see IEC 60947-4 which defines two types of Co-ordination between an overload relay and the short-circuit-protective-device. Only refers to motor protection.

Do you mean something else?

Actully I was looking for protection coordination in LV system of power plant or critical loads.

The IEC spec is one particular part of critical load protection, but if you think about it, all co-ordination (discrimination, cascading, etc) are similar in their objective viz. Isolation the faulty part with minimal disruption of power.

You can get lots of information from manufacturers on this, for example:

http://www.epowerengineering.com/guides-view-only.shtml

ECT 167

Have you referred to IEC 60255? And, IEEE 242?

Yaa, I have gone through IEEE standard, but it does not directly address coordination requirement and issues related to LV distribution system. This has been addressed in NEC.

I want to refer IEC before going ahead with my design

I yet to refer IEC 60255, I will have a look to it.

Shridhar Sir, many thanks for the link.

You are welcome, glad to have been of some help. You will get many more similar documents from reputed manufacturers like Siemens, ABB Eaton, LSIS and so on. Good luck.