Another Night, Another Pig…

Two in a row!

After going almost two weeks without catching anything I get two pigs in two nights. As usual the pigs came in to check on my compost pile. The sliced up apple proved too much a temptation and into the trap he went.

I have been been using apples from the sales rack our local village market. There is a shelf at the back where spoiled produce is placed at cut rate prices. A bag of bruised apples for a dollar makes good pig bait.

As you can see there is another pig outside the trap in the video below. Actually I think there are three more remaining in the neighborhood after this one. One big white spotted and two more smaller black pigs. The trap will be reset and ready tonight!

Black Friday Deal

Got a deal this Black Friday… A free pig. Deb heard the crashing in the wee hours as the pig expressed his displeasure at being trapped. No screaming this time, but lots of jumping about in the camera view.

A feral pig trapped in the garden.
A feral pig trapped next to the compost pile.

The pig war continues.

This makes four, with possibly up to four more to go in our neighborhood drove. The pig damage has definitely abated since the numbers have been reduced. particularly after I got mama a couple weeks ago.

The bait this time was a couple spoiled bananas that must have smelled good, the pig went right into the trap with no hesitation. You can see him push under the trip wire to close the trap.

This pig was removed from the neighborhood, never to eat my tomatoes again.

Pig Problems

I have had it with the pigs, stealing my ripe tomatoes crosses the line!

A feral pig trapped and ready for removal
Mama pig… Big, mean, and seriously not happy about being trapped.

The pigs have been around for months, but the damage had previously been minor. A mother and a litter of piglets caught on camera.

As the piglets grew in size so has the damage. Thus I find myself in the pig trapping business and learning the art of baiting pigs. It is not easy, pigs are wary critters.

The trap comes from a local guy who works for the village association, the result of a few emails to put us in touch. He stopped by a morning later with a very nicely made pig trap. Every few mornings I send him a text with an update, and occasionally a pic of the latest catch.

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A Better Solar Water Heater Electric Back-Up Timer

Another little problem around the house that can use a little creative circuitry to make it better. Do I really have to do it? No. I do it because I can, and because it is fun!

Solar Water Heater Back-Up Timer
A hot water heater timer setup for a solar water heater.
This time it is the electric back up heater for my solar hot water heater.

In Waikoloa solar hot water is an obvious addition to the house, we had it installed within a couple months of moving in. Considering electric power is about $0.40/kWh on the island, and tropical sunlight is quite intense, the use of solar to heat our water has been good money saving move… Long, hot showers with no guilt!

Once or twice a year we will get a period of heavy clouds and the water temperatures will fall to the point we need to turn on the electric back-up heating element in order to have that hot shower. Like most solar setups the storage tank has a electric element that will heat the water when needed.

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Modding the HBS

Just checking to see if I got the wiring right. Some modifications to the telescope HBS, Hydraulic Bearing System, to allow for a slower startup. Some new hydraulic valves installed by Mark, a few new relays added by me, and the job is done. Hopefully less sputter and spitting on startup to keep the oil off the drive tracks. The system is a classic relay logic controlled setup, seriously old-school.

Modifications to HBS
Just checking the wiring in HBS

Serious Apprehension

Today is the day I will close my eyes, cross my fingers, and press a button.

Old and New PLC's
The old and new programmable logic controllers installed in side the control cabinet.
If all goes well, 700 tons of steel and aluminum will move at that button press. the Keck 2 dome will rotate and I will be able to breathe again. There is just a little apprehension here. Replacing the controller that commands the motors and brakes has been my major effort for the last couple months. A great deal of time has been spent testing and retesting the software in the new controller.

Further tests will open and close the shutters. If anything this part is even more worrisome. The controller is responsible for releasing the brakes on the shutters. If the brakes were to open without motor power the shutters will be able to simply run downwards.

Fortunately they will not fall, but they can run downwards to the hard stops rather quickly. There will be a tech stationed at the shutters with a finger poised over the e-stop button during these first tests. The button blows the dome main breaker, which removes power from the brakes, causing them to close.

A brain replacement is fraught with opportunities for error. Currently the old and new PLC’s sit next to each other in the cabinet, installed last week. Monday morning I will remove the old one and slave the I/O cards to the new controller.

Then the testing begins.

A Matter of Control

As the new year is well underway I find myself in the midst of my major project for this year. For the next few months I will be replacing the control system for the Keck 2 dome. The project is well underway, but the real work remains ahead of me.

Keck 2 Dome PLC
The Allen-Bradley PLC/2 that controls the Keck 2 dome and shutters
It is a project that is long overdue. The current controller for the dome and shutters is an Allen Bradley PLC/2, a thirty year old piece of equipment that is sadly obsolete. Yes, a PLC, programmable logic controller, one of those machines I thought were a completely horrible way to do anything. I was appalled when I first encountered this technology, now I have to master it.

Parts for the PLC/2 are still available, but the programming software is a real issue. The software runs on a DOS (as in pre-windows) operating system, and does not run under the emulation modes of later Microsoft systems. You need a real DOS computer, something that is a bit rare these days. If the controller running the Keck 2 dome were to fail, I am not certain we could repair it.

I have the computer that is used to do the programming in my office, an ancient Compaq Portable III. Portable is an odd word to use with this computer, it weighs over 20lbs and is huge by modern laptop standards. This museum piece still works! Last month I booted it up and wandered through the file system. At power up I was greeted by a monochrome amber screen and a DOS prompt. I still remember a few basic DOS commands, enough to check things out. It appears that all of the software and files are still present on the hard drive. Sometime I need to see if I can indeed program the old PLC/2. If something goes wrong in the update I need to be able to revert to the original control system.

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