Lavspenning/Sporvekselvarme - TS Switch point heating system

1 SCOPE

This document describe requirements and recommendations for switch point heating systems for the Norwegian railway infrastructure. All facilities shall be proved by Norwegian National Railway Administration (NNRA).

The main function of the switch point heating system is to melt snow and ice that would else upset the functionality of the switch points — independent of the weather conditions. The functionality of individual switch point heating system should balanced the requirements depending on:

• melting process of snow and ice.
• climatic conditions (coastal area, inland, mountain area, tunnels etc.).
• snow and wind condition.
• energy efficiency enablement.

A switch point in this context is made up of one component that enables one of two distinct routes. A more complex switch point system shall be treated as two or more switch points.

The requirements and recommendations relates to:

1. complete switch point heating systems (cabinet, heating elements, fixtures, regulation system, transformers, sensors for temperature, wind and precipitation).
2. interface with external communication for commands and condition monitoring.
3. components as indicated above – to supply old facilities.
4. components as indicated above – to replace defect ones.
5. functionality to support the national switch point heating management system (NSPHMS).

2 REQUIREMENTS AND RECOMMENDATIONS

a) A local switch point heating system shall have communication with the national switch point heating management system (NSPHMS).

b) In case of communication downtime the local switch point system shall remain operating with all local functionality.

2.1 General requirements and recommendations

a) All communication and user interface shall be based on internet protocols, TCP/IP and Ethernet interface.

1. Bane NOR will provide fibre optic termination (router) or GSM-R modem.
2. The cabinet shall have dedicated space/volume reserved for fibre termination and GSM-R modem.
   1. Space requirement: w*h*d: 300*300*250 mm.

b) Necessary application protocols to be used interfacing with the national switch point heating management system (NSPHMS) shall be stated. The communication protocol should be public domain and based on industrial standards, see separate technical specification: TS_Format_i_meldinger.

c) The functions and set points of the local switch point heating system shall be remotely controllable. If extreme (weather) conditions are presupposed by the national switch point heating management system (NSPHMS), relevant actions may be applied.

d) All switch point heating system shall have a local regulation utilising information of ambient temperature and rail temperature.

1. Information on precipitation, snow condition, relative humidity and wind may as well be used.

e) If sensors should fail, the local system:

1. shall generate a fault messages indicating the change of state.
2. if the fault condition may result in accumulation of ice or snow, the local system should increase the melting power, if the outdoor temperature is below +10 degree Celsius.
3. faults in switching elements for heating elements may result in continious or no heating current in connected heating elements. With a redundant temperatur sensor connected to another rail (which is fitted with heating elements fed from a different transformer), it is possible to significant increase the correct function of the elements not directly affected by the faulty switching element(s).

f) The local switch point heating system shall be optimised to adopt the main functions of the national switch point heating management system (NSPHMS).

1. remote setting of parametric set-points.
2. reading of set-points, local temperatures, energy parameters etc.
3. “intelligent” alarm warnings (filtered).
4. local maintenance operations by local wired LAN or blue tooth interface.
5. local maintenance operations by global internet interface (via NSPHMS).

g) The local switch point heating system shall be optimised for efficient maintenance:

1. no or minimal interference with the train movements.
2. simple access to installed components.
3. no use of special tools (or if so, the tools shall be supplied) for maintenance.
4. components shall be fitted with labels for identification.
5. access to cabinets shall be secured by physical or electronic key(s).

2.2 Technical requirements and recommendations

2.2.1 Main objectives

a) Main objectives for the function of switch point heating system are depicted in
https://trv.jbv.no/wiki/Lavspenning_og_22_kV/Prosjektering/Sporvekselvarme and
https://trv.jbv.no/wiki/Felles_elektro/Prosjektering_og_bygging .

b) The equipment shall be marked, conforming to “Forskrift om elektrisk utstyr”.

c) The installer shall be registered by “Direktorat for samfunnssikkerhet og beredskap” (DSB).

d) The installer shall provide declaration that the delivered facility conform to:

1. Forskrift om elektriske lav-spenningsanlegg.
2. Forskrift om leveringskvalitet i kraftsystemet
3. relevant HD documents (NEK 400).
4. the EN 61439 series of standards (NEK 439).

e) The installer shall provide a quality plan including a risk analysis prior to delivery.

f) The installer shall provide a site acceptance test of the facility.

2.2.2 Power supply

a) The switch point heating system shall be designed for continuous operation with the maximum possible power consumption.

1. The cross section area of all conductors shall be sufficient to avoid heath problems.
2. The provider/installer shall ensure that the available source of power from utility is sufficient according to Forskrift om elektriske lav-spenningsanlegg..

b) The switch point heating system shall be feed from one of the following systems:

1. IT: 230 V and 50 Hz, three phase system without any neutral lead.
2. TN: 400 V and 50 Hz, three phase system.
3. IT: 230 V and 16 Hz, one phase system (non-prefered, should be avoided).
4. The provider shall give advice about any critical tolerances to the supply voltage, refer to Forskrift om leveringskvalitet i kraftsystemet .

c) All heating elements shall be feed trough transformers, providing galvanic isolation.

1. Transformers can accommodate for other voltages, however, 230 V shall be normative for heating elements in new systems.

d) For TN 400 V systems supplied from the utility the phase and neutral conductors shall only be terminated at the primary side of the transformer(s), and any protection earth conductor from the utility shall be isolated.

e) Disconnection of a transformer shall be done by all poles (L1, L2, L3 and any present N-conductor).

f) Non-resettable fuses is not allowed.

1. Non-resettable fuses shall have an electrical performance of minimum 1000 operations without failure.

g) The cabinet shall be fitted with auxiliary power supply from battery to maintain necessary supply to external communication (fibre optic connection or GSM-R modem) with the PLS for a minimum of 30 minutes if the main supply should fail. Absence of mains power shall be communicated.

1. Minimum energy for GSM-R modem or fiber optic modem at 24 Vd.c. and 25 VAh shall be provided.
2. Other components in the cabinet or fed by the cabinet - except for the PLS - do not need access to the auxiliary supply. (Note that the PLS needs power to communicate.)

2.2.3 Cabinet(s) for switch point heating system

a) Cabinets are regarded as electrical equipment and shall comply with:

1. “Forskrift om elektrisk utstyr”
2. EN 61439-1 (or NEK 439-1)
3. A compliance list shall be provided for each delivery.

b) The following design principles apply:

1. For a cabinet controlling only one switch point the transformer(s) may be installed in the same cabinet provided that a risk analysis is carried out and indicates moderate risk of environmental problems (heat, fire risk etc.).
2. The cabinet(s) shall be mounted on separate foundation(s).
3. Space should be allocated for an energy measuring instrument.
4. If requested, space should be allocated for over-voltage protection.
5. The cabinet should have allocations for components of the same voltage.
6. Each allocation should have a spare capacity (in volume) of 20 % for further components.
7. An earthing bar shall be fitted. At least one position shall have the capability to terminate Cu 95 mm².
8. Cable entrance shall be at the bottom of the cabinet(s) by nipples.
9. The volume beneath the cabinet(s) shall be protected by a skirt. If not otherwise stated, the distance between the cabinet and ground should be 40 cm.
10. All cables, insulated wires and material within cabinets containing electronic circuits shall be free of halogens.

c) The following design details apply:

1. The cabinet(s) with electronics should be with double metallic walls with a degree of protection of IP 54.
2. Any details fixed to the cabinet shall not ruin the degree of protection (IP 54).
3. Cabinet(s) should be fitted with regulated heating.
4. Cabinet(s) should have possibility for forced ventilation.
5. The cabinet door shall be provided with a lock. Information about the type of cylinder is provided by NNRA. The lock should be protected by a lid.
6. There shall be means to fix the cabinet door in an open position for maintenance.
7. The roof of the cabinet shall protect the cabinet door against rain and collected water.
   1. During local maintenance the roof should extend over the doors to protect portable electronic maintenance equipment.
8. All electrical termination in the cabinet shall be vibration-proof. This applies also for components and terminating blocks.
9. If the switch point heating system is operating a blue indication light shall be visible at the front (or back) of the cabinet.
10. External finish and colour should be agreed with NNRA. Provider should give advice about alternatives.
11. The cabinet should be fitted with a light and an outlet for 230 VAC/ 16 A for maintenance.
12. The cabinets shall be fitted with fixed or removeable lifting aids (padeyes) to ease transportation/movements.
13. Optional: A locally/remotely activated and time limited light external to the cabinet may provide illumination of the switch point(s).

d) The following requirements apply for documentation and marking:

1. All components should be permanently marked with identity – both on connecting cables and preferably on the components.
2. Cabinets shall have an external label, engraved with 25 mm text stating the identity of the cabinet and the voltage level. NNRA will provide the text (i.e. “SPORVEKSELVARMEGRUPPE 3, 230 V IT”).

2.2.4 Activation, regulation and supervision

a) The following requirements and recommendations apply for communication:

1. Each facility shall have its own unique identification (independent of communication services).
2. Each switch point shall have its own unique identification (independent of communication services).
3. The parameters controlling each switch point shall be locally stored in the SPHS.
4. The parameters controlling each switch point shall be controllable from the national switch point heating management system (NSPHMS).
5. The parameters controlling each switch point shall be readable from the national switch point heating management system (NSPHMS).
6. Actual values and environmental parameters in the local SPHS shall be readable from the national switch point heating management system (NSPHMS).

b) If a cabinet contains more SPHS's the control and operation may be coordinated.

c) The SPHS shall have functionality for energy efficiency enablement.

d) The following priority apply for activation of power to the heating elements:

1. High priority, abnormal condition: local/manual activation set from cabinet.
2. Normal priority, extreme weather conditions: time limited (hours only) activation with with request for increased power from the national switch point heating management system (NSPHMS).
3. Normal priority, normal operation: activated from the national switch point heating management system (NSPHMS).
4. Normal priority, normal operation: deactivated from the national switch point heating management system (NSPHMS) (parking – summer time condition).
5. Low priority, normal operation: Autonomous regulation in the SPHS of power to the heating elements, depending on ambient temperature, rail temperature, precipitation (snow, hail, rain, drizzling rain), wind, snow, ice etc.

e) The following requirements and recommendations apply for supervision:

1. Normal procedure for communication is a polling request or command from the national switch point heating management system (NSPHMS).
2. The SPHS responds to the poll with an acknowledge, a fault message or a status message.
3. Faults in a SPHS that is transferred to the national switch point heating management system (NSPHMS), shall be traceable in retrospect.
4. A SPHS in parking modus (summer condition) sensing a critical low temperature shall inform the national switch point heating management system (NSPHMS). Any actions shall be initiated from NSPHMS.
5. Energy consumption and actual elapsed time with power heating shall be reported to the national switch point heating management system (NSPHMS).
6. Actual elapsed time with forced power heating shall be reported to the national switch point heating management system (NSPHMS).

f) The following faults and conditions shall be reported:

• Earth faults, insulation faults.
• Faulty heathing elements, a fault indication for every heathing element affected.
• Faulty sensors.
• Faulty regulation (PLS).
• Abnormal activation of elements (locally activated in the cabinet).
• Maintenance activity (i.e. door open or manual activation).
• High rail temperature during active heating mode (i.e. more than 40 °C). (NOTE: It is recommended that the rail temperature may be requested in any mode.)
• “Input voltage out of range” (Forskrift om leveringskvalitet i kraftsystemet).

g) A (small ?) display shall be included in the cabinet to ease supervision (read out and tuning of set-points etc.).

2.2.5 Sensors

The number and type of sensors (i.e. temperature sensors, precipitation sensors, wind sensors etc.) depend on the actual system concept.

a) A sensor for measuring outdoor temperature shall be mounted in a closed ventilated volume to avoid influence of:

• sun shine
• percipitation
• conducted heat transfer from the environment / cabinet.

b) The temperature in rails shall be measured by sensors. One switch point connected to the cabinet shall be fitted with temperature sensors, preferably an important switch point within a through track.

1. The conductors of a sensor shall not be connected to the feeding cable protection earth.
2. The sensors shall be selected to avoid offset (resulting in faulty values for temperature) due to the cabling. Possible actions:
   1. three leads connection between the cabinet and the sensor (to compensate for voltage drop in the connecting cable)
   2. suitable resistance range (i.e. 1000 ohms PTC) of the sensor
   3. high electrical insulation and good thermal connection with running rail
   4. Sensors attached to rails shall be terminated with an oil-proof and flexible cable of 8 m and all conductors shall have the same cross section area.
3. At the switch toe a sensor should be fixed to the bottom of both the right and the left stock rail.
   1. The position should be just behind the second sleeper behind the first point machine.

c) If the cabinet controls a switch point with swing nose crossing with moveable point, the following applies:

1. The two sensors specified in b) above shall be fitted to this switch point.
2. An additional temperature sensor with the same specification as in b) above shall be fitted the bottom of the swing nose crossing between the two point machines to control the heating elements attached to the swing nose crossing and the wing rails.

d) The switch point system shall detect malfunction of the detectors by comparing the outdoor temperature and the temperature in the two stock rails and – if applicable – also the temperature in the swing nose crossing.

1. Any faulty sensor shall be reported to NSPHMS.
2. The regulation of heating elements shall compensate for a fault in one sensor (supposing a single-point-of-failure) to minimize the most severe impacts (i.e. no heating in cold climate or full continuous heating).

2.2.6 Transformer(s)

a) The provider shall depict the type of transformers to be used.

1. The transformer(s) shall be positioned away from the track.
2. The transformer(s) may be contained in a cabinet, in a shaft or on a foundation in free air.
3. The provider shall depict the IP protection for the transformers for the relevant position (cabinet, shaft, free air).
4. The inrush current for the cabinet shall be not more than 2,5 times the simultainous rms. current for all heating elements supplied by the cabinet.
   1. It should be possible to limit the inrush current by design, for instance by careful selection of transformers and/or asynchronous timing for activation of the relevant heating elements.
5. The transformer(s) shall have a termination point for protection earth.
6. The closure of the transformer(s) shall have one termination point for external protection earth of 95 mm².
7. The termination block for transformers shall have a capability to terminate a minimum of 10 mm².
8. The transformer(s) shall have durable labels with relevant information about voltages and capacity for low and full load – including short-circuit.

2.2.7 Heating of rails

The history of heating systems installed for the Norwegian railway system utilize heating elements fixed to the web of rails and similar systems are depicted in Fixed or flexible heating elements fixed to the web of rails.

Other solutions using electricity may be applied according to Alternative technology for electric heating systems.

2.2.7.1 General

a) Heating element shall be fixed to the track (stock rail, switch blade etc.). Provider shall depict installation procedure and fixtures.

1. Drilling in the rails or switch blades shall be avoided.
2. The position of elements shall be fixed mechanically close to the feeding cable. (The thermal linear expansion may be different for rails and for heating elements.)
3. The heating elements shall not have electric contact with the protection earth conductor of the feeding cable.
4. Any joint in the feeding connection shall provide external insulation, and the protection shall be a minimum of IP 67.
5. Any envisaged secondary protection should be stated.
6. For switch points with milled groves prepared for heating elements the heating elements should be installed in the milled groves.

b) The position of the connected end of heating elements should be at the far end (with reference to the tongue edge) to minimize cable movements.

c) The provision of heating elements shall be documented:

1. Drawings of the installed switch point with detailed position of all elements with feeding connections shall be provided.
2. The type(s) and total number of fixtures shall be provided.
3. Assembly guides shall be provided for installation and maintenance work.

Drawings of some different switch points is provided. Installed switch points may be of other design.

2.2.7.2 Fixed or flexible heating elements fixed to the web of rails

a) Voltage for the heating elements should be 230 VAC.

1. The heating capacity shall be a minimum of 250 W/m.
2. The heating elements should be optimized for maximum heath transfer to the rails.
3. The heating elements shall be installed to avoid cold zones – both on the stock rails and on the switch blades.
4. On stock rails the length from the out-most slide chair to 500 mm past the switch toe shall be fitted with heating elements.
5. On switch blades the whole moving length shall be fitted with heating elements.
6. Wing rails shall be fitted with heating elements.

b) Old switch points may need spare parts like heating elements with 60 VAC.

2.2.7.3 Alternative technology for electric heating systems

a) The heating technology shall be detailed depicted with mechanical design, heating capacity, electrical connection (voltages), attachment etc.

1. Any EMI problems with track circuit systems shall be envisaged.
2. Any energy efficiency enablement shall be provided.
3. Information about efficiency under different climatic conditions (precipitation, low temperature, humidity, wind, snow, ice etc.) shall be provided.

2.2.8 Rod heating

a) Rod heating element(s) shall be provided on request.

1. The rod heating element(s) shall not have electric contact with the protection earth conductor of the feeding cable.
2. Fixtures for the rod heating element(s) shall be depicted by the provider.
3. The rod heating element(s) shall be positioned to avoid contact with the rails.
4. The joint between the rod heating element and the feeder cable shall have insulation and the termination shall be a minimum of IP 67.
5. Relevant rod heating elements will typically be in the range of 500–1000 W.
6. Any additional secondary protection of cables, joints etc. may be provided.

2.2.9 Heating elements for swing nose crossing

a) Heating elements for swing nose crossing shall be provided on request.

1. The heating element(s) shall not have electric contact with the protection earth conductor of the feeding cable.
2. Fixtures for the heating element(s) shall be depicted by the provider.
3. The heating element(s) shall be selected and positioned to avoid obstruction with objects along the track.
4. On wing rails the length from the out-most slide chair to 500 mm in front of the swing nose crossing shall be fitted with heating elements.
5. On swing nose crossing the whole moving length shall be fitted with heating elements. There may be practical issues to adapt heating elements/parts to heat the actual area at the outmost part of the swing nose crossing. Interim solution may be to insert heating elements mounted on metal sheets between adjacent sleepers for the actual area. (Practices to be updated.)
6. The joint between the heating element and the feeder cable shall have insulation and the termination shall be a minimum of IP 67.
7. Any additional secondary protection of cables, joints etc. may be provided.

2.2.10 List of heating elements

Bane NOR aims to standardize on heating elements.

a) The preferred heating elements are depicted in Tabell 1.

1. Heating element for rails shall have a heating capacity of minimum 250 W/m up to a capacity of 350 W/m (unless otherwise stated).
2. Heating elements shall be fitted with a connecting cable of minimum 8 m.

Tabell 1: Heating elements.

F.number	Reference	Description	Connection	Length (m)	Min. power (W)	Nominal power (W)	Comment
To be defined	S-1 (2 pcs)	Track lock element	S	1,0+1,0	300+300		Mounted on both sides of running rail
To be defined	-	Slide Plate	-	-	aprox. 300+300		Two integrated elements per point machine to be fed (only power feeding (Alstom)).
To be defined	SR-4U	Rod heating element	S	4,0	1000		Mounted on a metal sheet (2 m) (Spare element only: see picture Figur 1.)
To be defined	SR-4 (2 pcs)	Rod heating element	S	4,0+4,0	1000+1000		Two elements
To be defined	SR-3	Rod heating element	S	3,0	900		Mounted on a metal sheet (3 m) (Spare element only: see S-3.)
To be defined	SR-1	Rod heating element	S	1,0	300		Mounted on a metal sheet (1 m) (Spare element only.)
To be defined	S-3	Rail element	S	3,0	750	900
To be defined	S-3,5	Rail element	S	3,5	875	1050
To be defined	S-4	Rail element	S	4,0	1000	1200
To be defined	S-4,5	Rail element	S	4,5	1125	1350
To be defined	S-5	Rail element	S	5,0	1250	1500
To be defined	S-5,5	Rail element	S	5,5	1375	1650
To be defined	S-6	Rail element	S	6,0	1500	1800
To be defined	S-6,5	Rail element	S	6,5	1625	1950
To be defined	S-7	Rail element	S	7,0	1750	2100
To be defined	S-7,5	Rail element	S	7,5	1875	2250
Implementation: S: Straight connection (0 degree) L: Angled connection (90 degrees) U: Angled connection (180 degrees).
Nominal voltage for all elements: 230 V.
All elements shall be terminated with a oil-proof and flexible cable with a length of minimum 8 m.

Figur 1: Picture of heating element SR-4U

b) The heating elements should be selected to use as few elements for the actual switch point. In principle 6,0 m elementes and adapted with more elements with length of 6,0 m or shorter.

1. Obstructions by point machines or other details may request for adapting heat element lengths.
2. Provitional data in Tabell 2 may be updated. Missing data will be supplied.

Tabell 2: Heating elements in switch points

Component	Rail	Heating elements implementation/ length								Comment (rail specification, etc.)
S54 R190 1:7	stock rail	S-4,5	S-4	S-4	-	-	-	-	-	Fil:OB.800157-000 000 001.pdf
	tongue rail	S-4,5	S-4	S-4	-	-	-	-	-	Fil:OB.800157-000 000 001.dwg
S54 R190 1:9	stock rail	S-5	S-5	S-5	-	-	-	-	-	Fil:OB.701286-000 002 001.pdf
	tongue rail	S-5	S-5	S-5	-	-	-	-	-	Fil:OB.701286-000 002 001.dwg
S54 R190 1:9	stock rail	S-6	S-6	-	-	-	-	-	-	Fil:OB.701334-000 002 001.pdf
	tongue rail	S-6	S-6	-	-	-	-	-	-	Fil:OB.701334-000 002 001.dwg
S54 R190 1:9 dkv	stock rail	-	-	-	-	-	-	-	-	Fil:OB.800167-000 000 001.pdf
dual switch point	tongue rail	-	-	-	-	-	-	-	-	Fil:OB.800167-000 000 001.dwg
S54 R500 1:12	stock rail	S-6	S-6	S-6	-	-	-	-	-	Fil:OB.701305-000 001 002.pdf
	tongue rail	S-6	S-6	S-6	-	-	-	-	-	Fil:OB.701305-000 001 002.dwg
S54 R760 1:14	stock rail	S-6	S-5,5	S-5,5	S-5,5	-	-	-	-	Fil:OB.701319-000 001 004.pdf
	tongue rail	S-6	S-5,5	S-5,5	S-5,5	-	-	-	-	Fil:OB.701319-000 001 004.dwg
UIC60 R300 1:9	stock rail	S-5,5	S-4	S-4	-	-	-	-	-	Fil:OB.800099-000 001 002.pdf
	tongue rail	S-5,5	S-4	S-4	-	-	-	-	-	Fil:OB.800099-000 001 002.dwg
UIC60 R760 1:15	stock rail	S-5,5	S-5,5	S-5,5	S-5,5	-	-	-	-	Fil:OB.701382-000 001 002.pdf
	tongue rail	S-5,5	S-5,5	S-5,5	S-5,5	-	-	-	-	Fil:OB.701382-000 001 002.dwg
UIC60 R2500 1:26,1	stock rail	S-6	S-6	S-6	S-6	S-6	S-6	S-6	S-6	Fil:OB.701399-000 001 001.pdf
	tongue rail	S-6	S-6	S-6	S-6	S-6	S-6	S-6	S-6	Fil:OB.701399-000 001 001.dwg
-	swing nose crossing	-	-	-	-	-	-	b	-
-	wing rail	-	-	-	-	-	-	-	b
60E1 R300 1:9	stock rail	S-6	S-4	S-4	-	-	-	-	-	Fil:OB.701408-000 000 002.pdf
	tongue rail	S-6	S-4	S-4	-	-	-	-	-	Fil:OB.701408-000 000 002.dwg
60E1 R500 1:12	stock rail	S-6	S-6	S-6	-	-	-	S-6	-	Fil:OB.800090-000 000 001.pdf
	tongue rail	S-6	S-6	S-6	-	-	-	S-6	-	Fil:OB.800090-000 000 001.dwg
	swing nose crossing	-	-	-	-	-	-	b	-
-	wing rail	-	-	-	-	-	-	-	b
60E1 R760 1:14	stock rail	S-5,5	S-5,5	S-5,5	S-5,5	-	-	-	-	Fil:OB.800108-000 000 001.pdf
	tongue rail	S-5,5	S-5,5	S-5,5	S-5,5	-	-	-	-	Fil:OB.800108-000 000 001.dwg
60E1 R760 1:15	stock rail	S-5,5	S-5,5	S-5,5	S-5,5	-	S4,5	S-4,5	-	Fil:OB.800164-000 000 001.pdf
	tongue rail	S-5,5	S-5,5	S-5,5	S-5,5	-	-	-	-	Fil:OB.800164-000 000 001.dwg
	swing nose crossing	-	-	-	-	-	b	-	-
-	wing rail	-	-	-	-	-	-	b	-
60E1 R1200 1:18,4	stock rail	S-6	S-6	S-6	S-6	-	S-5	S-5	-	Fil:OB.800081-000 001 001.pdf
	tongue rail	S-6	S-6	S-6	S-6	-	-	-	-	Fil:OB.800081-000 001 001.dwg
	swing nose crossing	-	-	-	-	-	b	-	-
-	wing rail	-	-	-	-	-	-	b	-
b: Best practice – practical solution to be implemented. Implementation: S: Straight connection (0 degree) L: Angled connection (90 degrees) U: Angled connection (180 degrees).

2.2.11 External cables

a) Buried cables shall have the necessary properties and protection to be positioned in the vicinity of the track.

b) Supplied cables shall have durable and visible markings in both ends.

1. Markings shall be provided in any manholes and drawboxes.

2.2.12 Environmental properties of equipment

a) The provider shall declare the equipment according to Table 51A in NEK 400 for the external influences:

• Temperature – AA
• Humidity – AB
• Water – AD
• Dust – AE
• Mechanical impact and crush – AG
• Vibrations – AH
• Low frequency phenomena (by conduction or radiation) – AM
• Sunshine – AN

2.2.13 Protective earthing

a) Facilities within the overhead contact line zone (OCLZ) shall be bonded to the track return circuit.

1. The bond between the main earthing bar to the track return circuit shall have a cross section area of 50 mm², 70 mm² or 95 mm² - depending on the installation site.
2. Transformers and equipment connected to heating elements shall be bonded regardless of the distance to the track. (In order to avoid remote hazards due to local faults of the contact line.)
3. Cable screens and PE conductors shall be protected from extreme currents originated from the contact line under fault conditions. Hence the particular cable screens and PE conductors of limited cross section area shall be terminated in one end only.

2.2.14 External communication with the NSPHMS

a) External communication with the national switch point heating management system (NSPHMS) is provided by either optical fibres or GSM-R.

1. For external communication the interface within the cabinet shall be a RJ45 outlet with Ethernet 1000BASE-T.

b) Protocols and related information is provided in a separate technical specification.

1. The protocol elements shall be documented.
   1. Mapping of information elements to physical elements (heat elements, sensors, set points, alarms etc.)
   2. Scaling and interpretation of integers, float numbers, flags and other information elements.

3 RELIABILITY, ENVIRONMETAL REQUIREMENTS AND DISPOSAL

a) The reliability of the switch point heating system shall be proved and characterized by figures for MTBF and MTTR (travelling activity excluded).

b) The existence of any hazardous materials in the SPHS shall be documented.

1. This apply for defect or outdated components that should be realized.

4 DOCUMENTATION

a) Maintenance guides shall be provided in Norwegian.

b) General requirements for documentation are provided at:
https://trv.jbv.no/wiki/Felles_bestemmelser/Generelle_bestemmelser#Dokumentasjon

c) Detailed data sheets shall be provided.

1. The language should be Norwegian, alternatively English will be accepted.

d) The type of requested documentation/drawings includes:

• Description of the facility and behaviour.
• Description of regulation concept and control.
• Block diagram and physical layout of cabinets etc.
• Main electrical circuits for feeding and control.
• Schematics for terminal blocks.
• List of electrical circuits.
• List of components.
• Detailed installation drawings of heating elements and fixtures.
• Drawings (projections and layers) of installed transformer(s) and cables.
• Detailed position of sensors.
• FAT protocol (factory acceptance test).
• SAT protocol (site acceptance test).
• Format for drawings: .dwg .
• Guides for substitution of defect components (heating elements etc.).

e) Declaration of conformance shall be provided.

1. The check list of compliance shall be provided.

5 REFERENCES

1. Forskrift om elektriske lavspenningsanlegg – (FEL)
2. Forskrift om elektrisk utstyr – (FEU)
3. NEK 400, Elektriske lavspenningsinstallasjoner, Norsk Elektroteknisk Komite
4. EN 61439-1, Low-voltage switchgear and controlgear assemblies - Part 1: Type-tested and partially type-tested assemblies, CENELEC, Bryssel
   Same as NEK 439A
5. EN 60947-7-1, Low-voltage switchgear and controlgear - Part 7-1: Ancillary equipment - Terminal blocks for copper conductors
6. https://trv.jbv.no/wiki/Felles_elektro/Prosjektering_og_bygging/Jording
7. https://trv.jbv.no/wiki/Lavspenning_og_22_kV/Prosjektering/Sporvekselvarme
8. https://trv.jbv.no/wiki/Lavspenning_og_22_kV/Bygging/Sporvekselvarme

6 CHECK LIST

	Confor- mance: (Yes/No)	Any comments
2	----	REQUIREMENTS AND RECOMMENDATIONS
	a)
	b)
2.1	----	General requirements and recommendations
	a)
	b)
	c)
	d)
	e)
	f)
	g)
2.2	----	Technical requirements and recommendations
2.2.1	----	Main objectives
	a)
	b)
	c)
	d)
	e)
	f)
2.2.2	----	Power supply
	a)
	b)
	c)
	d)
	e)
	f)
	g)
2.2.3	----	Cabinet(s) for switch point heating system
	a)
	b)
	c)
	d)
2.2.4	----	Activation, regulation and supervision
	a)
	b)
	c)
	d)
	e)
	f)
2.2.5	----	Sensors
	a)
	b)
	c)
	d)
2.2.6	----	Transformer(s)
	a)
2.2.7	----	Heating of rails
	---	Either of 2.2.7.2 or 2.2.7.3 applies
2.2.7.1	----	General
	a)
	b)
	c)
2.2.7.2	----	Fixed or flexible heating elements fixed to the web of rails
	a)
	b)
2.2.7.3	----	Alternative technology for electric heating systems
	a)
2.2.8	----	Rod heating
	a)
2.2.9	----	Heating elements for swing nose crossing
	a)
2.2.10	----	List of heating elements
	a)
	b)
2.2.11	----	External cables
	a)
	b)
2.2.12	----	Environmental properties of equipment
	a)
2.2.13	----	Protective earthing
	a)
2.2.14	----	External communication with the NSPHMS
	a)
	b)
3	----	RELIABILITY, ENVIRONMETAL REQUIREMENTS AND DISPOSAL
	a)
	b)
4	----	DOCUMENTATION
	a)
	b)
	c)
	d)
	e)