STANDARDS SAFETY DESIGN AND LEGISLATION
AS/NZS 61439 has been mandatory since May 2021 and is the new series of standards covering low-voltage switchgear and electrical control gear. Based on the International IEC 61439 standard its
was refined then adopted to suit the Australia and New Zealand electrical industries, retiring the previous standard AS/NZS 3439 after nearly 20 years.
POWINS invested heavily with both capital and innovative design improvements for the ECO BLOC PREMIUM range of MCC switchgear so that our resultant MCC product was industry leading and capable for service in voltage ranges of 415V – 690V – 1000V being fully type tested and compliant with AS/NZS 61439 set (2016), IEC 61439 set (2.0:2011).
The following is a brief of some requirements of the standard;
- Dielectric Test
- Short time withstand current and peak withstand current test
- Verification of IP coding
- Internal Arc test
A brief description of the tests are as follows:
Dielectric
These tests check that the switchgear has sufficient capability to withstand the lightning impulse and the power frequency voltage. The power frequency withstand voltage test is carried out as a type test, but is also routine on every switchgear unit manufactured.
Short Time & Peak Withstand Current
The test shows that the main power and the earthing circuits resist the stresses caused by the passage of the short-circuit current
without any damage. It should also be noted that both the earthing system of the withdrawable apparatus and the earthing busbar of
the switchgear are subjected to the test. The mechanical and
electrical properties of the main busbar system and of the top and bottom branch connections remain unchanged even in case of a short-circuit fault.
Verification of IP rating
The degrees of ingress protection for switchgear need to conform to Australian and International Standards, AS 60529 (2004) and IEC 60529 Standards (1989 +AMD1:1999+AMD2:2013)
Internal Arc
When developing modern low voltage switchgear, personnel safety must necessarily take first place and this is why the ECO BLOCK PREMIUM switchgear has been designed and tested to withstand an internal arc due to a short -circuit current of the same level as the maximum short -time withstand level. The tests show that the metal housing of the switchgear is able to protect personnel working near the switchgear in the case of a fault which evolves as far as striking an internal arc which conforms to AS/NZS 61439 Appendix ZD.