Cause of the Recent Electric Trains being grounded, the fix, and what mitigation is being taken to prevent it in the future

Ben Ross made this Official Information request to Auckland Transport

The request was partially successful.

From: Ben Ross

Dear Auckland Transport,

I am enquiring about the recent "intermittent power fault" that grounded the Electric Train (EMU) fleet from Wednesday 23rd July until the evening services of 31st July.

Specifically please I am seeking the following information about that grounding:

1) What caused the intermittent power fault that lead the eventual grounding of the EMU fleet on 23rd July.

2) How was that intermittent power fault caused that lead the eventual grounding of the EMU fleet on 23rd July.

3)Why did the intermittent power fault happen when possible smaller versions of the fault occurred ever since the EMU's began revenue service on the Onehunga Line in late April. These smaller faults causing EMU's to shut down and often force cancellations or delays of other services such as seen on the 21st and 22nd of July. In light of that could have the intermittent power fault been prevented if proper tests were carried out before the EMU fleet went into revenue service on the Onehunga Line

4) What did Auckland Transport (and partners - if applicable) do to fix the fault to allow EMU's to resume revenue services as of 31st July

5) Will the fix mitigate against any future intermittent power faults that could cause groundings of the EMU fleet

6) Is Auckland Transport looking at other mitigation techniques apart from the fix to prevent future intermittent power faults grounding the EMU fleet again

7) How many substations were built to power the electrified rail system and the EMU's

8) How many substations WERE PLANNED to be built to power the electrified rail system and the EMU's.

9) If less substations were built than planned then why was this the case AND could the lack of substations be a mitigating factor that caused the intermittent power fault

10) Is Auckland Transport investigating whether the 110kv National Grid line that follows the Onehunga Line from Penrose to Onehunga Station could be causing the interference thus intermittent power fault with the EMU's.
If not why is Auckland Transport not investigating this.
If so what are the results or will we know the results publicly.

I look forward to your reply

Yours faithfully,

Ben Ross

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Attachment CAS 354682 L4K9Q8 Ack.pdf
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Good afternoon Mr Ross,

Please find attached an acknowledgement for information requested under
the Local Government Official Information and Meetings Act 1987 from
Auckland Transport.


Kind regards



Jo Garwood | Auckland Transport
6 Henderson Valley Rd, Henderson, Auckland 0612
Private Bag 92250, Auckland 1142

P 09 355 3553 | F 09 355 3550 | [1]

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