AS/NZS IEC 60947.5.8:2015 pdf download – Low-voltage switchgear and controlgear Part 5.8: Control circuit devices and switching elements—Three-position enabling switches
5.2 Marking 5.2.1 General Marking of data specified in items a), b), c) and d) of 5.1 is mandatory on the nameplate of the three-position enabling switch in order to permit the complete information to be obtained from the manufacturer. Marking shall be indelible and easily legible, and shall not be placed on screws and easily removable parts. Whenever space permits, data under items e) to o) of 5.1 shall be included on the nameplate, or on the three-position enabling switch or otherwise in the manufacturer’s published literature. 5.2.2 Terminal identification and marking Subclause 7.1 .7.4 of IEC 60947-1 applies. 5.2.3 Functional markings To avoid confusion with emergency stop devices, the actuator of an enabling switch shall not be coloured RED (see also IEC 60204-1 ). 5.3 Instructions for installation, operation and maintenance Subclause 5.3 of IEC 60947-1 applies. 5.4 Additional information Subclause 5.4 of IEC 60947-5-1 applies. 6 Normal service, mounting and transport conditions Clause 6 of IEC 60947-1 applies with the following additions. 6.1.3.2 Pollution degree Unless otherwise stated by the manufacturer, a three-position enabling switch is intended for installation under environmental conditions of pollution degree 3. However, other pollution degrees may apply, depending upon the micro-environment.
7 Constructional and performance requirements 7.1 Constructional requirements Subclause 7.1 of IEC 60947-1 applies except for 7.1 .1 , 7.1 .2, 7.1 .6, 7.1 .8 and 7.1 .1 2, and with the following additions. 7.1.1 Materials Subclause 7.1 .1 of IEC 60947-5-1 applies. 7.1.2 Current-carrying parts and their connections Subclause 7.1 .2 of IEC 60947-5-1 applies. 7.1.3 Clearances and creepage distances Subclause 7.1 .3 of IEC 60947-5-1 applies. 7.1 .4.3 Actuating force (or moment) The force (or moment) required to operate the actuator shall be compatible with the intended application, taking into account the size of the actuator, the type of enclosure or panel, the environment of the installation and the use for which it is intended. 7.1 .7 Class II three-position enabling switches Subclause 7.1 .7 of IEC 60947-5-1 applies. 7.1 .8 Requirements for three-position enabling switches with integrally connected cables Subclause 7.1 .8 of IEC 60947-5-1 applies. 7.1.9 Three-position operation The three positions are designated as follows (see Figure 2): − position 1 : OFF state of the contact (actuator is not pressed); − position 2: ON state of the contact (actuator is pressed to the normal enabling position); − position 3: OFF state of the contact (actuator is fully depressed). The three-position enabling switch pressed to position 2 shall return to position 1 when released. The three-position enabling switch shall change from position 2 to position 3 when pressed further. When released from position 3 to position 1 , the switching element shall not close when the actuator passes through position 2. Figure 1 illustrates the three positions and the corresponding contact states.
7.2.3 Dielectric properties Subclause 7.2.3 of IEC 60947-5-1 applies. 7.2.4 Ability to make and break under normal and abnormal conditions Subclause 7.2.4 of IEC 60947-5-1 applies with the following addition. 7.2.4.3 Durability Three-position enabling switches shall be tested according to 8.3.3.6. 7.2.5 Conditional short-circuit current Subclause 7.2.5 of IEC 60947-5-1 applies. 7.2.6 Switching overvoltage Subclause 7.2.6 of IEC 60947-1 applies. 7.2.7 Additional requirements for control switches suitable for isolation Subclause 7.2.7 of IEC 60947-5-1 applies. 7.2.8 Shock and vibration Shock or vibration shall not cause opening of closed contacts or closing of open contacts. The tests shall be conducted according to 8.3.5.2 and 8.3.5.3. 8 Tests 8.1 Kinds of test 8.1.1 General Subclause 8.1 .1 of IEC 60947-1 applies. 8.1.2 Type tests Type tests are intended to verify compliance of the design of the three-position enabling switches with this standard. They comprise the verification of: a) temperature rise (8.3.3.3); b) dielectric properties (8.3.3.4); c) making and breaking capacities of switching elements under normal conditions (8.3.3.5); d) making and breaking capacities of switching elements under abnormal conditions (8.3.3.5); e) performance under conditional short-circuit current (8.3.4);f) constructional requirements (8.2); g) degree of protection of three-position enabling switches, if applicable (8.3.1 ); h) durability (8.3.3.6); i) shock and vibration (8.3.5). 8.1.3 Routine tests Routine tests are the responsibility of the manufacturer and are usually limited to a mechanical inspection and a verification of the electromechanical operation. The inspection shall be supplemented by a dielectric test which is carried out according to 8.3.3.4 with the following amendments: the required minimum duration of voltage application is reduced to 1 s and the metal foil and external terminal connections are unnecessary. Additional routine tests for the three-position enabling switch may be specified as appropriate. A sampling plan may be accepted. 8.1 .4 Sampling tests Subclause 8.1 .4 of IEC 60947-1 applies. 8.1.5 Special tests These tests are subject to agreement between manufacturer and user. 8.2 Compliance with constructional requirements Subclause 8.2 of IEC 60947-1 applies except for 8.2.5 and 8.2.6. 8.2.5 Verification of operation of three-position enabling switches The requirements of 7.1 .9 are verified by operating the actuator while monitoring the state of the contacts. The monitoring means shall be capable of detecting a contact closure longer than 0,2 ms.