Wednesday 2 January 2013

The excited alternator

I always like sorting a problem out.... I get frustrated when it is a problem I have previously resolved and forgotten about. The case in point being the charging system on Percy.

On New Years eve we ended up in lamp light as the batteries were giving a good impression of blocks of useless black plastic holding lots of acid and no charge. Frustrating as I had run the engine for a few hours in the day time.

So yesterday I set to with my trusty multi meter to understand what was going on. On tickover (I estimate about 200rpm...) the alternator was giving about 5 volts.... as was the case with our Shared boat Sylph, the alternator need 'exciting' to kick it into giving a charging output. So a quick wind on the speed wheel gear to cruising rpm.... 600 I estimate then about 14.5v on the back of the alternator and battery charging commenced.

I checked the three batteries 2 x leisure and 1x starter (easy to get access in the engine room) and they were well topped up.

I then set to reconnecting the solar panel and controller..... all very temporary as the final install will see all cable runs on copped tubing, so I will need my blow torch, soldering stick and flux to make the joints look as good as possible as there are no 'Yorkshires' on the job to date....The sun was doing its job as we connected up giving 16.5v in to the controller with the batteries reading a poor 11.38v. The controller is a MTTP one that has 4 stages of charging and has done a great job of keeping the batteries up to spec on Waterlily. It will be interesting to see the state they are in when we are next back aboard... very soon !



The final bit of good news was the inverter ran the Dyson.... I was expecting to have to get the genny out each time we wanted to vac up. But the excellent no name inverter ran it very well. A full deep clean will still see the genny used as the Dyson will strip the batteries quite quickly even with the engine running. As the two batteries are lowly 94 a/h of unknown age I am not too concerned about them as I have a couple waiting delivery via my neighbour Kev.

As with my other boats it is a learning curve.... but when a solution is found made more enjoyble.

I must blog about the water pump challenge and Rachel's shower testing -anyone seen the Homer Simpson episode when Bart gets a tune out of Homer by changing the shower temp with a tap downstairs.....;-)

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