Piha Generators during September storm

The night part of this video is very dark although the audio of the diesels cranking and firing up is great.
Grey 40 ft container 1.8 MVA 16 cylinder 60 liter Mitsubishi diesel.
Yellow 20 ft container 800 kVA 12 cylinder Caterpillar diesel.
Main 11kV supply lines were damaged because of fallen over trees in the storm.
Temporary power by means of diesel generators.

Category:

Science & Technology

Tags:

• NZ
• generators
• Piha
• storm
• clag
• power
• outage
• starting
• cranking
• diesel
• turning
• over
• V16
• V12
• electricity
• Caterpillar
• Mitsubishi
• demarré

[frazzledude]

I have a question. When you connect these hired generators to the electrical grid, how do you know the rotation/phase order is correct? It seems to me that there is a 50/50 possibility that all of the 3 phase motors powered by these generators could start up turning the wrong direction. Is there a standardized order for the three phases in the New Zealand electrical distribution system?

[RODALCO2007]

@frazzledude Good question. This location has frequent power cuts and the phase rotation is known and marked in the connection points.

The phase rotation is normally clockwise at the generator terminals and is checked prior to livening.

In genral the phase rotation should be clockwise for R-Y-B or A-B-C or L1- L2- L3 but on many transformers there is a 50 / 50 chance that it is wrong.

[Nivicoman]

I take it that those diesel prime movers are ok with spinning up to 1500 rpm right away instead of having an idling/warmup period?

[RODALCO2007]

@Nivicoman The big 12 and 16 cylinder engines usually get a 10 minutes warm up with no load before the braker is closed.

[BarneySaysHi]

Man I love the sound of those big engines starting. Where I used to work we had 4 backup generators, 2 MW each. They were heated day and night so they could deliver their power instantly. Datacentres, gotta love them for big generators.

[RODALCO2007]

@BarneySaysHi We ran these generators for 15 minutes prior to loading them up.

In this emergency case they were started cold, ran with no load for about 15 minutes and then the load was applied. In the day part of the video's we had 2 trips as the impedance + load were to high and the over current protection kicked in.

3 rd time it held after part of the 11kV load was switched off by means of an isolator switch 1 kn away.

[treybolinger]

Amazing that this is just a big engine that is making all the power. Two things I like, nerdy engineering, and automotive technology.

[ChumpusRex]

Are these low voltage generators connected to the transformer secondary? Or are the big ones medium voltage?

At work, our backup generators are all 11 kV - except for 2 'oh crap' backups which are 400V and used for secondary backup for the most critical areas.

[frazzledude]

@RODALCO2007 Okay. That makes sense. Thanks for the answer.

[stdavross666]

@ihatespam1977 common practice in australia also. Western power advertises split system ac for years ...so efficient, blaa blaa and then cant keep up with demand. now theres ads on tv telling people not to use there air con. dipshaits.