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As I have mentioned in the overview page, I've been getting very fed up with the constant number of power outages that we have in the Adelaide Hills, and even more so with the significant damage that has happened to my equipment on three occasions. On 19 March 2007, after the third incident, I called ETSA and asked for an explanation. On 20 March I received a phone call from Shaun, who promised to tell me what the situation was.
At the end of this discussion I was more upset than before. Shaun seems to have no idea about the material he is talking about, and the main cause of his call seemed to be to explain how it isn't ETSA's fault. Here some of the details of the 35 minute call:
The power failure on 10 January 2007, during which my 5 kVA UPS (uninterruptible power supply) was seriously damaged, was caused by the CFS turning off the power. There was no power spike, no power surge.
The problem with the UPS was that I should have powered it off. UPSs are designed to enable people to power down a system in an orderly fashion, not to maintain power, and they can be damaged if they are turned on when the power comes back. Thus it was my fault for not turning the device off.
In fact, I had turned it off. At the start of the outage the UPS had gone into a fault condition, so I had turned it off until the power came back. When I powered it on, as I said at the time,
Put the UPS back in circuit and—it blew up! Noise and smell of sparks, and it not only blew both circuit breakers, but even after I reset them, we had no power in the computer rooms, so I had to lay cables from other rooms.
Shaun seems to be very vague in his understanding of what a UPS is. He started his discussion by talking about the problems of starting motors and such, which of course has nothing to do with a UPS. He also doesn't appear to know what the term UPS stands for. According to him, a UPS is power board with battery backup, and is not designed to resist surges.
I suggested to him several times that he should reconsider this claim, since it goes against the basis of having a UPS, but he was adamant that this was correct, and he had no need to reconsider.
The 4 hour power failure on 1 March 2007 was caused by a failure of a low voltage insulator, which had been struck by lightning, and had affected 568 people.
This statement is incorrect. See the linesman's view for the real story: ETSA hasn't isolated the problem yet.
The momentary interruptions are caused by “reclosers”, a circuit breaker like device that automatically resets after a second or two. Only if they fault persists do they stay off. He gave reasons such as tree branches, birds and possums, and stated that this was not a network fault. When I asked him why they didn't go out and check whether it was a tree branch, he told me that it was not ETSA's responsibility to keep lines clear of branches. I asked him to reconsider this one, too, but again he was adamant. He doesn't seem to know that ETSA has a whole department devoted to keeping foliage away from power lines.
ETSA monitors recloser activity, but in many cases the information needs to be collected manually. It would be too expensive to have automatic reporting, since they would have to lay data transfer lines. I pointed out that they were physically located on a line, so he changed his tack and just said it would be too expensive. Clearly he is making comparisons with things he doesn't understand.
They will send some people out to do a quality of service investigation (what Lisa called a voltage investigation), which will probably involve monitoring the line voltage for a few days. I said that these problems only ever occur during power failures, but that didn't seem to interest him.
The nominal line voltage in Australia, 240 to 250 V, has no basis in fact. The law says that the voltage must lie between 216 and 253 V, and power will fluctuate constantly between these values. When I told him that this didn't happen, and that I was prepared to bet that the line voltage was currently 248 V, be said that I was very lucky not to have flickering.
Voltage surges occur only when there is lightning activity. There was no lightning on the 18th, so there was no voltage surge.
Talking further about what happens when the power comes back after an outage, he said that the “power returns with a rush”. When I asked what this meant, he started off with an inappropriate analogy about water and hoses, and said that the power returns instantaneously with no delay whatsoever, presumably so defying the speed of light. I asked him what happened to the voltage and current during this time, but he was obviously out of his depth. I didn't think until later to ask him whether we should bleed the air out of the power lines.
I asked him whether he meant that there would be no difference between plugging in an appliance with the power switch turned on, and having it connected when the power came back. He said yes. I then asked whether he realized that most countries in the world don't have switches on power sockets; he disagreed. I asked him what countries outside the British Commonwealth had switches on the power sockets. He gave France and Italy as examples. When I told him that they most definitely did not, he was surprised and concerned about the safety; he's obviously also never heard of recessed sockets.
It wasn't until later that I realized this was not the issue. The switch at the wall is irrelevant; the idea that he was promoting was that you should power off the device with its own on/off switch. And of course, many don't have them. In the case of the two computers damaged in December 2005, they were turned off.
I asked him how we should be expected to turn off all power during a recloser event, which only lasts a couple of seconds. He obviously wasn't able to answer this one even to his own satisfaction.
Finally I asked him why it was that we have so many momentary power failures here, when in the 6 years I lived in Schellnhausen in Germany—also with overhead power lines—we had only had three. I made the mistake of suggesting that these were recloser events, because they also only lasted a few seconds, and he pounced on this, saying that this was a supposition. I answer that it was a pretty reasonable one, but irrelevant. He didn't try to answer my question.
In summary, he said very little of any value and only managed to antagonize me.
On 21 March 2007, the following day, I got a call from Mark, a linesman (is that the correct description?) Anyway, somebody who understands what he is talking about. He wanted to know the transformer number for our transformer, and I was able to give him enough information to identify that. He also told me:
The event of 1 March took such a long time to resolve because they weren't able to find the fault. They brought back the power area by area, and it all just worked. They suspect a damaged insulator that may be reacting to moisture.
The subsequent recloser events are probably related to the problem, and they're really not sure what is causing it.
His experience is also that the voltage is constant, and in his case it is also not only higher than average, but at 256 V higher than allowed.
His son has also had a computer power supply burnt out by a power failure. There can be a considerable spike when the power comes back.
In other words, a sensible explanation of the situation. If his voltage is consistently over the legal limit, I get the feeling that there is a general problem. The fact that they still, after 3 weeks, have not been able to isolate the problem almost certainly means that they have inadequate technical means at their disposal.
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