What is safe?

STC-1000 Temperature Controller
STC-1000 Temperature Controller

Designing and building equipment for aquaculture means I use controllers. Quite a few controllers, dozens upon dozens of them, little boxes meant to keep some parameter in range. Temperature, pH, water level, whatever, a little box with a display, a few buttons, and a relay in the back to turn something on when needed to control the outcome.

Industrial suppliers will sell you a controller for just about anything, there are catalogs full of them, from inexpensive to thousands of dollars you can buy the solution to your needs. Buy one, wire it in, adjust a few setpoints and you have everything under control.

Enter the STC-1000, a little cheap temperature controller found on eBay, Amazon, everywhere. It comes in a bunch of different versions, need readout in Farenheight or Centigrade? No problem. I have no idea who makes it, some asian factory somewhere. It is available in a hundred different brand names from hundreds of different sellers for somewhere between $12 and $25, all absolutely identical as far I as can tell.

The STC-1000 is cheap. Cheap enough that I am somewhat suspect of their reliability. I do not buy them for production line bioreactors and grow tanks, places where I cannot trust a cheap controller with a few thousand dollars worth of product. For critical uses I buy full industrial rated temperature controllers from a reputable supplier for around $100 each.

But for experimental setups? Temporary research hacks built with more limited budgets? There are a couple dozen of these STC-1000 controllers around the place. They are easy to use with simple configurations, seem to be accurate holding calibration, and I have not had one fail yet.

So how do you sell a device like this for about $15?

Time for a little deconstructive analysis…

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Electrical Hazard

Over the last week at work we have been preparing an unused part of the facility for use. We need a place for an industrial freeze dryer and a walk in cooler. But first we had to clear out a massive pile of junk that had accumulated, and do demolition on a lot of old equipment and piping to remodel the space.

A burned and melted power receptacle
A burned and melted power receptacle

Demolition? Break out the sawzall! We used a big sawzall, a small pile of saw blades, an angle grinder with a diamond cutoff wheel, a bit of muscle and a lot of sweat to get it done. The pile of trash accumulated rapidly along the fence, old lumber, a lot of PVC pipe, and a lot of rust… A big dumpster will appear later.

Rust. This close to the ocean everything is badly corroded, do not even try to release the old bolts, just pop a fresh battery into the angle grinder and let the sparks fly. The 20 amp sawzall does not use batteries, good for the thicker pipes and framed walls, it rips through PVC like butter.

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Visiting the Summit of Mauna Kea

Visiting the summit of Mauna Kea is high on many visitor’s to-do list when coming to the island. The summit region is spectacularly beautiful, even after six years of visiting several times a week I still find it so. My habit is to drive, or to ride shotgun in order to enjoy the view. I keep a camera at hand, ready for the inevitable situations where beautiful is transformed to spectacular with a well placed cloud or shaft of sunlight.

Summit Visitors await Sunset
The usual crowd of summit visitors await sunset along the ridge between the Gemini and CFHT telescopes
Any visit to the summit starts by stopping in at the Mauna Kea Visitor Information Center. Located at 9,200ft the center is found at the end of the paved road. The folks here are responsible for providing visitor information and helping you out if you get into trouble, a service provided by the observatories through Mauna Kea Support Services. This includes the Mauna Kea Rangers who patrol the mountain, providing information, advice and assistance to visitors. Also found at “The VIS” are bathrooms, a gift shop, and the evening star gazing program.
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