MoominPapa

You're maybe thinking about the rubbish point and tap at Barbridge Junction? The Shroppie around there is pretty good for facilities: it's not far between Nantwich and Calverley. I think the tap at the junction was nominally replaced with on above the first lock on the branch. MP.

This is useful info for me, as my maximum charge rate is about 70A and maximum sustained discharge rate is lower than that. Looks like I'm in the sweet spot. ETA, I think for new LFePO4 systems, there's a strong argument for 24V or even 48V. MP. MP.

Some of the drift is down to measurement errors, but a lot is down to unknown and variable charge efficiency. LA batteries need to be regularly charged to 100% and as they approach 100%, the proportion of the electrical energy used in turning lead sulphate into lead oxide decreases, and the amount used in turning water into hydrogen and oxygen increases. The H2 and O2 are lost from the system. so any energy that goes that way is not stored in the battery, and the actual stored energy is lower than that determined by measuring what goes in. Since the proportion of the water splitting side reaction and therefore charge efficiency depends quite strongly on the state of charge and physical state of the battery, how much it has aged and deteriorated, it's very difficult to compensate for this in the AH counter. Apart from the energy loss, and some water loss which is easily replaced, these side reactions don't damage the LA cells, and they do some good: the bubbling fixes stratification and the because most-charged cells start to gas first, this allows cell balancing without any external balancing system. On the other hand, the equivalent side reactions in Lithium cells are bad news, and must not be allowed to happen. Hence sophisticated BMS system with charge termination and external cell balancers. So, because side reactions are avoided in Lithium cells, the charge efficiency is higher and more predictable, so a major source of error in Ah counting doesn't exist. MP.

There are lots of possible explanations, but the most likely is just systematic error in the current measurement hardware, especially as it's Hall-effect based, which are known for small biases due to residual magnetism after heavy current flow. MP.

At some point, I can't remember exactly when, but certainly over a year ago, I added code to my BMS to keep a running total of charge and discharge. It's currently at ~30000Ah, so assuming average battery voltage of 13v, that's 0.39MWh. I think these batteries are going to last a long time. Interestingly, either there's a small zero offset, or I've invented a perpetual motion machine, the exact figures are charge: 29947.02Ah and discharge: 30934.53Ah. MP.

No problem with the BDS-A in my system, at least so far. It was new, and not second hand. One thing to check: there is a preferred current direction through the contacts. This doesn't help much when both charge and discharge go through the contactor, but if yours just does charging, make sure it's connected the correct way around. The direction ensures that the magnetic field helps to extinguish the arc (though from your tear down, excessive arcing is not your problem.) MP.

Really? In cars, the slower charging uses a mains-fed charger in the vehicle, to minimise the cost the fixed infrastructure, but fast charging is DC. The fixed infrastructure for fast charging is more expensive, but the stuff in the vehicle is reduced to a socket, some contactors, and the cabling between them. All the power electronics are external to the vehicle. I've always thought that the idea for boats is fast charging whilst at water points, etc. Just because it's much easier to get power there than to the sort of places where boats tend to overnight. To control costs, the exact same infrastructure as is use in cars needs to be employed, as that furnishes a huge market and wins economies of scale. MP.

Nothing much to add. The Moominbats are still going great guns. No noticeable degradation at all. They really are the dog's bollocks. MP.

No Moomins, unfortunately. We were planning to drive down, but our daughter has come down with Covid, and that's messed up the plans, for complicated reasons. MP.

I guess that includes the towpath in Woodseaves cutting, which is blocked by a load of fallen sandstone. The towpath for the whole length has not been used or maintained and looks like it may never be used again. MP.

The auto vent won't vent excess pressure: the mechanism holds it closed when not inserted into a toilet, but doesn't positively open it when activated. That's because to can be closed by a float when the cassette is full. That lifts a rubber flap which seals the vent. If the flap is closed and positive pressure builds up in the cassette, that will hold the rubber flap in the sealed position. The yellow vent button is the best way to release any excess pressure. MP.

I'm perfectly capable of inspecting my boat to determine if it's safe, so I just want the piece of paper to give to CRT; the cheaper the better. MP.

I think the implication is that all are welcome, straight or any colour of the rainbow. MP.

I was wondering that. You'll be forever first choice as weed-hatch wallah if so. MP.

GWS Tree Monkey. BlueStringPudding please keep us informed. MP.

I picked up a very second-hand but functional electric strimmer from the bin compound at Norbury Junction today. Perfect for DIY mooring creation. Judging by how the edges are growing already, everyone's going to need one, so I'm ahead of the curve. MP.

It's also entirely possible I misread the sign as we passed. It wasn't very clear. MP. We couldn't remember if Turner's did gas, and we were desperate. Good to know that they do. MP.

On Tuesday, Turners were 129.9 and Norbury were 128. Our main reason for stooping at Norbury was that we needed gas too. MP.

The Australian one, obvs. also Grazebrook Arm.

Add Pensnet Basin to the bag.

Melaleuca is checking out Parkhead before the competitors arrive tomorrow.

Or maybe not. Something in the lock entrance.

BCN, the umpire is in you.

In the challenge spirit, we bagged the Fens Branch and Stourbridge Extension Canal. MP

I remember. 18 months ago but feels like half a lifetime.