BS EN 50578:2013
$102.76
Railways applications. Direct current signalling relays
| Published By | Publication Date | Number of Pages |
| BSI | 2013 | 18 |
This European Standard gives requirements for direct current relays intended for safety-related applications in railway signalling installations.
This European Standard is applicable to monostable relays. However it can also be used as a guide for other relays such as with bistable relays.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 5 | Foreword |
| 6 | Introduction |
| 7 | 1 Scope 2 Normative references 3 Terms and definitions 3.1 all-or-nothing relay 3.2 armature 3.3 bistable relay 3.4 bounce time |
| 8 | 3.5 break contact (for elementary relays) 3.6 change-over contact 3.7 contact gap 3.8 contact member (for elementary relays) 3.9 contact force 3.10 contact point 3.11 contact wipe 3.12 drop-away current 3.13 electromechanical relay 3.14 elementary relay 3.15 make contact (for elementary relays) |
| 9 | 3.16 monostable relay 3.17 nominal current 3.18 operate condition (for elementary relays) 3.19 pick-up current (compression) 3.20 pick-up current (service value) 3.21 relay with forcibly guided (mechanically linked) contacts 3.22 release condition (for elementary relays) 4 Classification |
| 10 | 5 Essential requirements of the relays and their construction 5.1 Generic requirements for signalling relays 5.1.1 Forcibly guided (mechanically linked) contacts 5.1.2 Forcibly guided (mechanically linked) operation 5.2 Specific requirements 5.2.1 Relays of type N 5.2.1.1 These shall be characterised by their non-weldable make contact points, through the use of a suitable contact point material (for example, silver-carbon for which there is no risk of welding above a certain percentage of carbon), or by the int… 5.2.1.2 The relays shall open the make contacts by falling of the armature under its own weight, when the current is interrupted in the coil. 5.2.1.3 The relays may also be equipped with return springs. These return springs shall only be used to increase the contact force of break contacts and ensure that the required time parameters for the armature to fall are met. They shall not be used … 5.2.2 Relays of type C |
| 11 | 5.3 Mechanical construction of the signalling relays 5.3.1 Connecting devices 5.3.2 Materials 5.4 Environmental conditions 5.4.1 General 5.4.2 Vibrations and shocks 5.5 Magnetic system 5.5.1 General 5.5.2 Requirements for new relays |
| 12 | 5.5.3 Functioning during service 5.6 Design of insulation 5.6.1 General 5.6.2 Overvoltage |
| 13 | 5.6.3 Test voltage 5.6.4 Case of a supply circuit not connected to earth 5.6.5 Pollution 5.7 Contacts 5.7.1 Spacing 5.7.2 Break contact 5.7.3 Contact heating 5.7.4 Service life |
| 14 | 5.7.5 Minimum distance apart of the relay contact elements 5.7.5.1 The values given below shall not vary by more than 40 % during the service life, on the understanding that the distance between two make contact elements is never less than its initial value. 5.7.5.2 Non-weldable contact points: 5.7.5.3 Single or double contact points of weldable material used in equipment concerned with safety: 5.7.5.4 Contacts with double spacing of weldable material used in equipment concerned with safety: 5.7.6 Contact force 5.7.7 Self-cleaning 5.7.8 Bounce |
| 15 | Bibliography |
