Random Writings

I’ve had a very good day today. It started auspiciously at Screwfix, when they had all four of the things I wanted, and therefore clearly the gods of DIY were looking favourably on me…
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I now have a working inverter/charger on the boat! Back at Easter I started a big electrical upgrade of the boat, fitting new batteries and some new internal wiring. But I was hamstrung by not having the right terminals on the cables to the inverter. I called around Cambridge’s extensive range of electricians’ merchants (“electrical wholesalers” to use the jargon) and eventually found one firm, Hedley & Ellis, who were prepared to help. Unfortunately, their giant crimping tool (a thing about the size of a large pair of boltcutters or a tree lopper) was out on hire. It returned yesterday. Today I cycled into town with about 10kg of copper cable in the bike panniers, got the terminals crimped on for the princely sum of £5, and then this evening I’ve wired it all up.

And it works! The batteries charge quite rapidly, and I can now run the generator in economy mode (where it adjusts the throttle according to the load) which should hopefully save me quite a lot in petrol.

Probably next weekend I’ll fit the SmartGauge battery monitor and split-charge system so I can charge the domestic batteries from the engine, and after that I’ll have to do something about the wiring spaghetti on the kitchen wall!

Simulink is a companion to Matlab which purports to be a time-flow simulation package. This post is going to get quite technical, so if you’re not into either communications system design or Simulink in general, look away now.

I’ve used Simulink before, in my third year at York, but that was following a well-structured lab script where the lecturer had partially set up the models in advance. This time I’ve been doing a course (I’m obliged to do one of Leicester’s engineering MSc modules in my first year) simulating communications systems in Simulink, and the lab script is much vaguer. I’ve spent a lot of time banging my head against a brick wall in Simulink, and here are some important gotchas that might save other people going through the same level of auto-cranial damage.

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