Part 4 of 5

Low Voltage and High Voltage Energisations

In part 2 of 5 of this mini series on the Testing and Commissioning process for new railway lines, we established how we believe you should organise the T&C team to make sure it can deliver on the project’s T&C Strategy in an effective and safe manner.

A key member of your team, provided you are involved with the construction and commissioning of an electrified railway line, is the Power Supply Manager.

As the T&C Manager you need to appoint your Power Supply Manager as head of the Electrical Permit Office and the ‘Power-On’ team for both Low Voltage and High Voltage energisations at each of your sites. The Power-On team will follow the requirements of the IRN procedure (see part 3 of 5 for details) before any follow up energisation is authorised and will adhere strictly to the project Electrical Safety Rules as enforced by the Permit Office.

If you do not have a set of Electrical Safety Rules in place at this stage then you probably should take a step back and address this gap ASAP…

To protect both the integrity of the installation and relevant personnel working on, or in the vicinity of, the equipment, no initial energisation should be possible without the prior acceptance of the Power-On team following the issue of an IRN for the ComLot concerned.

Once the equipment is live, its control and the delivery of the relevant permits to work for the safe isolation of the equipment shall transfer to the T&C Lead Engineer through the authority of your Power Supply Manager.

To keep everyone well informed (and safe), energisation notices must be included in the WAD Notice that is published by the WAD Manager or WAD Coordinator(s) on a weekly and daily basis (see part 3 of 5 for details).

Traction Power Energisations

Among the Elementary Systems to be tested and commissioned on a new railway electrified line, either the Conductor Rail or the Overhead Line Equipment system needs to go through a specific process before its energisation can be permitted.

As seen in part 1 of 5, the T&C process is usually divided into four different phases. Phase 3 generally focuses on the integration of elementary systems that have been installed and pre-commissioned during phase 2.

The Traction Power system shall not be energised before the end of phase 3, once integration of the relevant supporting systems such as earthing & bonding, distribution assets and ‘SCADA’ have themselves been installed and verified. Indeed, the energisation of the Traction Power itself and the series of post-energisation testing activities that are necessary to verify the integrity of the systems are usually the last of the integration tests to be carried out prior to Dynamic Intergation Testing commencing.

One of the main reasons why you should energise the Traction Power at the end of phase 3 and not before, is firstly because of the dangers surrounding the presence of a 1000 D.C to 25 kV A.C. ‘live’ overhead line catenary or 650V-750V D.C. conductor rail(s) on what would still be considered a construction site under the CDM regs 2015, with many ‘non-railway’ minded people still being around.

Secondly, because there is no real value in energising the Traction Power unless it is to be used by electric trains for testing purposes in the immediate future.

Last but not least, the minute the Traction System gets physically ‘interconnected’ with the potential source of its electricity, the systems falls under the Electrical Safety Rules and thus any outstanding works become much more difficult to complete.

Energisation Strategy

Together with the T&C Manager, the Power Supply Manager must prepare a robust Energisation Strategy that must take into account key programme constraints and the strong probability that not all of the railway line could be energised at once. This is a very important document, in particular if you are being forced to allow outstanding construction activities to continue in other adjacent sections of the line whilst you are about to increase the dangers of electrocution tenfold in the sectors where your T&C Team is supposed to be tightly controlling all accesses to the site.

The Energisation Strategy not only should address how you intend to implement and control impeccable zones segregations, it should also dictate how remedial works post first energisation will continue AFTER first energisation has taken place. Because whether you like it or not, nine times out of ten, outstanding construction and remedials works will resume, sometimes potentially with unexpected intensity, even after you have managed to get the Traction Power energised.

Agreed, it should not be the case and things should be sufficiently complete not to have to worry about this possibility. But trust us when we tell you that it is too often not the case, unfortunately. As a result you need to be prepared to have extremely solid and workable procedures in place before that situation materialises, including having fully anticipated the re-training/re-induction of the remainder of the workforce on the dangers of working in the vicinity of Traction Power equipment that is now ‘live’.

It is your responsibility as T&C Manager to ensure they fully understand the new and even more dangerous environment these critical energisations will generate and how it will dramatically impact their working routine. Not getting the message across loud and clear could be a recipe for disaster.

Savvy and experienced Project Managers know full well the risks of deadlocking a project with stringent but unavoidable electrical safety rules and the sudden exponential increase in the time it takes to complete some of the simplest tasks. Not even mentioning the similarly exponential increase in project costs…

Those Project Managers endeavour to complete most of the critical construction/installation works that affect the rail corridor and the main electrical equipment rooms well in time for first energisation, as they know it will be almost mission impossible for them to deliver on their promises once the T&C Team takes over the control, operation and maintenance of the newly installed Traction Power network.

Energisation Packs

On a complex project, a decent Energisation Strategy should always introduce the notion of ‘Energisation Packs’.

There could be one or several packs, each relating to a particular energisation sector that has been pre-determined in advance of the initial energisations.

The purpose of a pack is to list all of the pre-requisites that are required to be met before the project executives, representatives of the External Facility Networks, External Railway Networks and other Notified Bodies, feel comfortable enough to allow the Traction Power to be energised for the first time.

Beyond the usual test procedures to be contained within the ‘pack’ such as ‘Section Proving’ and ‘Short-Circuits’, a number of other deliverables are required, including but not limited to:-

• 6 months and 3 months Notices of Energisation to Local Authorities, External Railway and External Facility Networks;
• Specific WAD Notice(s) for Traction Power Energisation;
• Comprehensive approved Traction Power Sectioning and isolation diagrams;
• Commissioning Switching Schedules;
• Land line telephones installed and operational at critical locations;
• EMC Management Plan, in particular the mitigation measures agreed for the proximity and direct interfaces with the External Railway and External Facility Networks;
• Engineering Safety Cases for Energisation;
• HAZID report(s);
• Insulation and Continuity test results 48 hours before each energisation;
• Documented final walkthrough 24 hours before each energisation;
• Removal of construction earths in the conductor (where applicable);
• Compliance with Earthing & Bonding requirements;
• Relevant safety signage;
• Special Arrangements including buffer section at the Interface with External Railway Networks and/or other sectors of the line still under construction.

Traction Power Status post-Energisation

The Power Supply Manager must ensure that the Traction Power can be safely operated post-energisation as the system will come “under the rules” immediately when the substation feeders are connected up. Although the Traction Power on an operational railway is normally ON and is only switched OFF and earthed when a planned isolation is requested, you would be very wise NOT to apply this concept to a construction project.

Although technically the Traction Power will de facto be considered ‘live’ at all times from first energisation onwards and this will be reflected in any briefing/training given to the workforce, you better make sure your procedures dictate that it is normally OFF and it will only be switched ON when required for implementing further tests or to run an electric train during Dynamic Integration tests and beyond.

It is far too dangerous to do otherwise. But it is also foolish to advertise when it may be ON and when it may be OFF and people need to learn that in the absence of a proper Permit to Work that they hold in their hands, there is a very serious possibility that the system is fully energised and deadly dangerous as a result. Cables thefts and other niceties in the late stages of a project are despicable but not unusual events. One does not want to tell thieves exactly when they are safe to go and steal from you in a ‘safe’ and effective manner…

Other key Preparations

To cope with this change in the construction site rules the T&C Manager is to ensure that a specific number of items within the ‘Energisation Packs’ which do not relate directly to the testing and commissioning of the Traction Power system, are nevertheless dealt with before the energisation can take place, such as:-

• A fully approved set of Electrical Safety Rules;
• The withdrawal of existing authorisations and training certification now becoming obsolete;
• Mandatory upgraded training/induction for all personnel still present on the project who will require access to the site post Traction Power energisation;
• Permits to Work dedicated booklets capturing the changes in the environment;
• Nominated, Authorised and Competent Person personnel available, fully familiar with all site accesses and fully trained;
• Live testers and earths available, calibrated, certified and in sufficient number;
• Operational Switching Schedules for access and maintenance purposes (post-energisation);

From experience we advise that both the Energisation Strategy and the Energisation Packs’ need to be prepared a minimum of 6 months prior to the initial Traction Power energisations. Note in particular that the Notices of Energisation to Local Authorities, External Railway and External Facility Networks must be sent a good 6 months before the event too.

Not complying with such a strict timescale will likely impact the date of your Traction Power energisation. External Railway and External Facility Networks in particular have their own clients to satisfy and to protect from the potential adverse effects of you energising the line for the first time. Be fully prepared to answer many questions related to how your energisations may interfere with the integrity of their own adjacent, directly or indirectly connected safety critical systems.

From experience again, ensuring that an agreement is met across all the stakeholders could take up to two years ! In particular if the only way the External Railway and/or External Facility Networks can be satisfied that nothing ‘bad’ will happen when you flick the switch ON, is by booking possessions outside of normal traffic hours when nobody can work on the adjacent operational railway or facilities and by supplementing this with monitoring tools and teams to observe and record the possible effects of switching things ON for the first time.

And that’s not it because you will have to take the same precautions again when carrying out short-circuits and probably again when running an electric train on the line for the first time.

If the elementary systems have been designed, installed and commissioned as they should be, these monitoring and observations you have to put in place, for peace of mind and as a prerequisite to getting the green light to proceed, will record…well, absolutely nothing !!! But you never know, so they need to be in place for your various energisation stages.

You also need to be prepared to repeat the process for each sector that gets energised for the first time, one after the other. Hence why a strategy is so important and why these things can take an awful amount of time to implement. Indeed it is not unusual for the whole Traction Power energisation process to take several weeks. And that is when everything is running smoothly…

SCADA Integration

The integration of the Traction Power system with the SCADA system (supervisory control and data acquisition), is a big part of its commissioning.

No energisation should be attempted until the vast majority of I/O have been tested ‘dead’ to the full satisfaction of the SCADA Lead tester. The problem with SCADA is that it changes all the time. New updates get delivered regularly and a lot of testing may need to be repeated from one version to the other.

Assuming that is out of the way, then you have to deal with the issue of alarms raising all over the place. And knowing when to react to alarms or when to ignore them is quite an art in itself.

On a construction site as opposed to an already operational railway, some equipment may still need to be connected up so it is likely alarms will be raised in the system for lack of equipment sitting at the end of a circuit. Your Power Supply Manager needs to take the time to identify and inhibit the sometimes very long list of alarms that are irrelevant and focus on those few that are absolutely critical. Not a simple job and always a moving target as equipment missing on Monday may become operational on Thursday and the alarm should therefore be considered real if triggered.

This alarms business alone should be the subject of a joint document written between the Power Supply Manager and the SCADA T&C Lead to help the temporary electrical controller sitting at the desk make relevant decisions when alarms get triggered, either to acknowledge and make the relevant calls for people to address or to simply ignore. Without such a document in place, that may need to be updated on a weekly basis if not a daily one, the desk controller will be unable to assess the seriousness of an alarm.

Picture this: Alarms are going off like fireworks, the screen is lighting up like a Christmas tree, and our desk controller is left to decipher which alarms need immediate attention and which are just false alarms. Without a joint document that provides clear guidance, we are setting them up for chaos. And you don’t want to be running around like headless chickens rushing to contain a substation fire that doesn’t even exist!

Conclusion

Energisations, in particular the Traction Power energisations on a newly installed railway line, signal the beginning of an exhilarating new chapter. This phase, though laden with so many challenges, promises great satisfaction for the T&C Team if handled with precision and care.

However, it is crucial to proceed with caution.

Rushing the energisation process without ensuring that all the relevant ‘dead’ tests are complete, all procedures and emergency protocols are in place, and everyone is fully briefed can lead to very serious complications, or worse… Taking the time to verify every detail will pave the way for a smooth and successful energisation, setting a strong foundation for the exciting times ahead with the start of Dynamic Integration Testing, that will be explored in our part 5 (and last) of our mini series on the Testing & Commissioning process for new Railway Lines.