Col_T

Er, the picture does not show DC breakers between the panels and the MPPT.

Depends on whether you can connect to shore-based electricity. If you can, then leaving the charger should charge the batteries - assuming it is connected to them, of course! If you cannot connect to shore power then leave the inverter charger turned off, which shouldn't affect solar power - as you may well have a solar controller which charges the battery.

This seems to be saying that two-pack is best, if you can find a yard that will apply it properly, but that even professional coating companies struggle to get right. That being the case, two-pack seems to be spending more just because you can. Not always the best reason.

It's a lot of "if's" but if you have a boat-hook and if the bottom of the rudder is about the deepest part of the boat and if the rudder is accessible from the stern then hook the boat-hook under the bottom of the rudder, hold it there for 30 seconds or so (to get the pole wet so that the level is easily read) and then measure the distance from the curve of the hook to the watermark. Whether that is accurate enough is for you to decide!

Seems to me that you've just visited an Elsan station. You will usually find a tap next to the bowl (which is where folk like me empty their cassettes) and often that tap will say something to the effect that is does not supply drinking water. I've no idea if it contains chemicals to help break stuff down, but there's no way I would use that tap to fill my water tank.

We often turned our 57' nb there. The offside can be shallow if the pound is down on water, but what would one expect. Oh, it is not marked as a winding hole.

Okay, so shunts are something else I don't understand! I kind of thought that 75mV shunt would send 75mV per amp to the meter, which then needed to convert the mV number received into amps e.g. 300mV translates to 4 amps (value received divided by 75(mV) = amps). If that is the case, the calculation for a bi-directional shunt might need to 'centre' the reading. For instance, a shunt measure -5 amps to +5 amps would return a voltage of 375mV at 0 amp current flow. is that all total borrox???

What happens if there is a mismatch between shunt and ammeter e.g. a 100 amp shunt connected to a device that can read up to 200 amps? Just a random thought.

@dmr A particular problem is modern boats that for some reason are quite deep but don't have the big prop/heavy engine so are not so good at fighting their way out of the silt, my friend has one of these and she gets stuck everywhere. I suspect that is the problem with our boat - it has a Beta BV 1505, so about 38hp flat out, and a prop blade is about 8 maybe 8 1/2 inches long (I guess that equates to a 17" propeller). @dixi188 We came off the Oxford summit on Friday - stirred quite a bit of mud and probably helped carve out some new routes through the silt. We tend not to speed, don't much like the sound of breaking wash, so slow and gentle was the order of the couple of days we there. Generally not too bad.

Thanks, chaps. Kind of what I expected.

We've spent 3 1/2 years on the K & A, frequently grounding where other boats are moored, or just going aground letting other boats past us. Now we're having a cruise up the Oxford and the same thing is happening - yes, I know the Oxford is narrow and shallow. However, I've just measured from bottom of skeg to waterline, and answer is approx. 30 ins. Is this unusually deep for a modern, built 2002, narrow-boat?

With apologies for being an ignoramus, what is that spreadsheet and chart telling us, Dr. Bob? Column headings, at least, might be helpful.

Thanks, chaps. It all becomes clearer bit by bit!

Using LA as a dump load for when the lithium battery is charged to the specified level - does anything need to use the LA as a source, or is it in the design purely to receive the alternator trickle charge once the lithium charge is complete?

Thanks for this, Tony. Exactly the thing I was hoping for.