design philosophy

Why I over-design electrical systems

"Why", I'm sometimes asked, "do you specify electrical stuff that's bigger and more powerful than I had expected?"

It's a justifiable question. Batteries are expensive, heavy and bulky; why would you want any more of them than necessary? And what's with the multiple shutoff switches, subpanels, and other non-typical features of my electrical designs?

Criticality One

Anything that people make is going to break. This is inevitable. It's a direct consequence of unavoidable, fundamental laws of the universe.

Part of the art of engineering is to control where, and after how long, things will break. We can't prevent failure entirely, but we can focus our efforts on the most critical items and we can ensure that the complete system – an engine, boat, spacecraft, whatever – is unlikely to fail at all within a certain service life.

Weak Links

Is there an advantage to designed-in weak links, where a cheap and easily replaced part fails so that a more expensive one can be saved?
In many cases, there is; nevertheless, we shouldn't apply this design philosophy to everything we design.

Simple systems: It's about design, not quantity

What do we mean when we say a boat's systems are "simple"?

There's a temptation, at times, to say that simplicity is about cutting back. About leaving out whole systems to save on installation and maintenance dollars. I don't think that's really what it's about.

What we're really looking for when we say "simple" is, more often than not, elegance. Maintainability. Reliability. The least complex, least costly way to fill a stated specification. The ability for the captain to understand, and repair, every system on the boat.

Risk mitigation philosophies from the radiation world

Quite a few issues of safety, in the yachting world, come down to the preferences of the skipper and crew. There will never be universal agreement on how (or if) to use tethers, or on where a life raft should be kept, or on whether an extra EPIRB is a better investment than an AIS-B transponder upgrade.

We can, however, apply some general principles of risk analysis and risk mitigation at the design stage. The maritime world already has some ways of figuring this out, but for today, I think I'll shake things up a bit with some principles from a different field: ionizing radiation.

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