IEC 61992-4-2015 pdf free download.Railway applications – Fixed installations – DC switchgear- Part 4: Outdoor d.c. disconnectors, switch-disconnectors and earthing switches.
The purchaser shall specify the minimum number of auxiliary contacts required.
The auxiliary wiring connected to a circuit at 1 000 V a.c. or 1 500 V d.c. or above shall be physically separated from those connected to a circuit at a voltage below these limits.
For other characteristics of the auxiliary circuits, the requirements of 5.5 apply.
6 Construction
6.1 General
All apparatus and connections for the safe and satisfactory operation, control and protection of the equipment concerned, shall be provided whether or not specifically mentioned. The equipment shall be earthed. insulated, screened or enclosed as may be appropriate to ensure the protection of the equipment and safety of those concerned in its operation and maintenance.
Control and auxiliary circuits and contacts shall comply with the requirements of 5.2 of
IEC 61992-1.
6.2 Materials
No materials containing asbestos shall be used in the construction of the switchgear.
NOTE Special attention should be paid to the ability of the material used to resist moisture and fire: materials used should be of the self-extinguishing type, so that the risk of propagation or rite is min,mised (see Annex B of
IEC 61992-1).
6.3 Arcing contacts
Arcing contacts, if any, which are liable to be consumed during arc interruption shall be easy to replace.
6.4 Clearances and creepage distances
Clearances and creepage distances shall be not lower than those indicated in IEC 61992-1, Table 1 and Annex 0 respectively.
NOTE Clearances and creepage distances may be increased to take into account the presence of foreign substances after the number of operations, in normal and short-circuit conditions, occurring during the normal lifespan between cleaning procedures.
Where applicable, ribs shall be provided in order to break the continuity of conducting deposit which occurs during operation.
The clearance between open contacts shall be not less than indicated in Clause A.2 by reference to Table 1. of IEC 61992-1. clearance B. In case of units with double break, the sum of the two isolating distances in series shall exceed the minimum value required by 25 %.
6.5 Primary connections
The units shall be equipped with fixed or removable (bolted) connections.
6.6 Location of the primary connections
Their position shall be agreed between purchaser and supplier, unless covered by an IEC standard.IEC 61992-4 pdf download.