How to meet the new EU railway energy standards?
This Q&A is based on the results of Eress Forums’ workshop “How to meet the New European Standards”. Open questions and pending EU standard issues will be followed-up by Eress through workshops and at Eress Forum 2018.
Activity to determine, directly or indirectly, that a process, product, or service meets relevant technical standards and fulfills relevant requirements. Assessment can include inspection and examination of a product, its design and manufacture.
How could the conformity assessment be simplified and so reduce costs?
It is possible to choose an independent NoBo (Notified Body), even from another country. A certification of an EMS (Energy Measurement System) in one country, also applies in another country.
Why do we have to ask the NSA (National Safety Authority) acceptance in different countries?
Installing an EMS has an impact on the safety certificate. This safety certificate also verifies some national requirements and is thus country dependent. Adding an EMS shouldn’t have a significant impact on the vehicle’s core safety certification. Therefore, we can ask the NSA to try to simplify and standardise also the impact of Energy Measurement System on this safety certificate. An existing national verification (by the NSA) should be cross accepted.
Can the sensor output be shared with another system and still be used for international billing?
Yes, this is permitted as long as this doesn’t have an impact on the accuracy nor data security.
What should we do when TSI’s (Technical Specifications for Interoperability) and EN 50463 (EU norm that describes the specific requirements for on-board Metering Systems) have different requirements than national rules?
Requirements of TSI are after adoption also national rules. You will need to contact your regulatory bodies and/or government in order to change any conflicting national regulation. The easiest solution might just be a decision that clarifies that some national regulation is not applicable or that conformity to the TSI is an accepted alternative to the national rules.
Recalibration and reverification
Do suppliers offer tools to be able to recalibrate a sensor? Who has already experience with this?
Some manufacturers offer products able to recalibrate the sensors on-board. Others require dismounting of the sensor. Removing (or replacing) of a sensor is a costly process in the high voltage circuits. Train operators should take into account these costs while comparing offers of different EMS suppliers.
Is more standardisation needed regarding recalibration and reverification?
Some participants of the last Eress Forum requested to have more standardisation, e.g. regarding accuracy tests over lifetime, ageing tests and recalibration procedures. Also not having a fixed period of recalibration of sensors and meters was requested. This, because an inductive transformer normally doesn’t need to be recalibrated. A shunt (resistor used as component in current measurement function) is sensible to ageing and its output can change over time. In such cases a recalibration after some years is essential. The meter itself might not need any verification, but might need a periodic replacement as some components might start to fail after 8 to 12 years. Recalibration and reverification are based on the proven experience of the EMS supplier. This information is introduced during the initial conformity assessment. After acceptance by a Notified Body, these requirements are introduced in the maintenance plan of the rolling stock.
(Click here to see the Conformity Assessment Guidelines)
Regulatory and standardisation framework
What is not yet sufficiently specified?
Most participants agreed that the legal framework is good and sufficiently detailed. The new regulation clarifies the last open issue, i.e. the communication from EMS to DCS (Data Collection System).
What about 1 minute resolution?
The TSI and EN define 5 minutes as the Time Reference Period for CEBD (Compiled Energy Billing Data). So, conformity assessment will be based on 5 minutes data. This doesn’t exclude to send data on a shorter time period. Erex system is able to collect also 1 minute values and aggregate them to 5 minute values.
Do we need a conformity assessment for a DCS (Data Collection System)?
Today, there is no assessment required from the Energy TSI. The testing requirements defined by the clause 5.6 of EN 50463-3:2017 are quite limited. The Energy TSI currently places the obligation for the DCS implementation on the member state. Consequently, the member state might add extra requirements. The requirements in TSI and EN are regarded to be sufficient, so adding extra national requirement is not wanted at all.
What about the settlement system?
The settlement system needs to be better specified and standardised. Validation rules need to be described in a clear way. The UIC working group revising UIC leaflet 930 tries to improve this. Please show your interest and join this working group. According to the existing regulation for the Energy TSI, the obligation for the settlement system implementation is placed on the member state. Consequently, the member state might add extra requirements.
When will the EN 50463:2017 become applicable?
The application date is not clear. The EN 50463:2017 will replace the EN 50463:2012 likely on the 1st of January 2018. This is now published as such on the CENELEC website. The final date for replacing the 2012-version will be published in the new 2017-standard as dow (date of withdrawal of previous standard). The TSI from November 2014 remains applicable until the new TSI will be published in 2018. The clauses of EN referred to, from this TSI from November 2014 haven’t changed. The EN 50463:2017 only has big changes concerning the new standardised communication protocol.
Who should offer services using the data coming from the Reading Block or real time measurements? Should this be offered by the EMS suppliers, an independent software company or Eress?
The workshop groups proposed that Eress should collect and read out this data. So, Erex would become more than just a settlement and billing solution. The data exchange is standardised in EN 50463-4:2017. But the information needed and use cases will vary from country to country. An Infrastructure Manager will have other needs than a Train Operator. Therefore, it might be difficult to set up a standardised product offering. The workshop participants considered it OK to have a central provider of services, if permission is given by the data owner and access is granted to the correct data only via a login system.
Created Wednesday, July 12, 2017