SNZ AS/NZS 2081
Electrical protection devices for mines and quarries
|Publication Date:||4 November 2011|
This Standard sets out the design, performance, manufacturing, and testing requirements for electrical protection devices for use in surface and underground mines and quarries, where IT supply networks are utilized, and provides information on the general principles of-
(a) earth fault current limitation;
(b) earth continuity protection;
(c) earth fault protection;
(d) earth fault lockout protection;
(e) NER integrity protection; and
(f) frozen contact protection.
1 Whereas this Standard is based upon 50 Hz supply systems, it is envisaged that the equipment described may also be installed in systems with higher, lower or variable frequencies, or in d.c. supplied systems.
The effect of current upon the human body in 50 Hz supplied installations needs to be considered as detailed in AS/NZS 3000.
AS/NZS 60479, Parts 1 and 2 should be referenced for consideration of the effects of current at other supply frequencies upon the human body.
2 Refer to Appendix A for general information on the principles of electrical protection relevant to this Standard.