Helco power outages this evening?

[TomK]

Just curious if anyone in the Puna district experienced Helco power problems at around 7:30-7:45pm this evening (Friday 20th March). We experienced two big glitches in both Hilo and on the summit of Mauna Kea which have caused serious problems for us, but wondered how widespread the problem was.

Thanks in advance.

[terracore]

We had a couple of power hiccups in Orchidland at the same time but the power stayed on.

[ericlp]

Three magical words for you... Uninterruptible power supply's! Roll your own! and never be without power again!

http://www.dansdata.com/diyups.htm


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[Lee M-S]

we had 2-3 winkouts, just enough to make the satellite TV to spend 10 minutes resetting.

><(((*< ... ><(("< ... ><('< ... >o>

[Lin W]

We had a couple flickers last evening, found this posted on a Facebook HPP forum at 7:37p ... no other info.

"Transmission line bumped out between Wailuku and Pepeekeo."







I don't know how I got over the hill without getting to the top.

[TomK]

Thanks, everyone. Seems Lin's information was pretty good. I got a reply fro Helco this evening confirming a problem on the Hamakua coast. Helco teams found eucalyptus bark on a power line, which I assume means another albizia-caused problem.

Eric, we have a UPS, but even small glitches in switching power can cause serious problems with sensitive equipment.

[ericlp]

Tom, if you read the article.

You probably have a cheap UPS, What you need is an always "ON LINE" UPS. You can get offshelf ones but they are expensive.


A dual conversion UPS like this runs the inverter all the time. Most UPSes don't do that. They're "standby power supplies" instead, in which the inverter only runs when mains power fails. The rest of the time, they just pass mains power through to the output, maybe with good filtering, maybe without. The standby design makes the UPS more efficient, and also allows cheap units to have lower quality inverters, because the inverter hardly ever has to do anything.

There are also "line interactive" UPSes, which run the inverter all the time, though not at anything like full capacity; they also pass mains power through, while it's available. When power fails, the already-running inverter just picks up the slack.

Dual conversion, or "on-line", UPSes provide the best power filtering of the three flavours of UPS, and have no "cut-over" delay if the mains fails. But for domestic purposes there's not much difference, besides price, between the three.

This do-it-yourself UPS may be dual conversion, but it's about as elegant as it looks. Most people wouldn't want it.


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[kalakoa]

always "ON LINE" UPS

An off-grid power system is effectively an on-line UPS with a non-grid power source.

[TomK]

Thank you Erik, interesting stuff there. I'm no expert on UPS systems but can assure you ours is not a cheap off-the-shelf system! We had to order new batteries recently and all one ton of them was delivered by a truck.

No matter, I'll do a bit of research to see if we can get something better. I don't recall the cost of our UPS but suspect it was a few hundred thousand dollars. Not something we can replace every couple of years as the technology improves, but maybe one day we'll replace it as funding allows.

Our UPS is designed to keep the essential systems going so the observatory can be closed down in the event of a significant power failure.

However, when that UPS was installed, we typically only experienced one or two power failures a year. In the last three or four years, Helco power outages at the summit have increased exponentially. It's a serious problem for all the telescopes, especially as many are now switching to remote operations.

[kalakoa]

suspect it was a few hundred thousand dollars ... power outages at the summit have increased exponentially

A few hundred $K would put up lots of solar panels and plenty of battery, or at least buy a fully on-line UPS, so I'd start looking at other causes (flakiness in the UPS, bad ground), maybe rig something to chart the UPS output.

Old-fashioned isolation transformer might be a good workaround...