Electric wiring conventions and kit

[Keith M]

That's the point, the whale gulper just keeps working year in year out - no checking or cleaning needed!

 

Ours was on the boat when we got it so of unknown age and has been working faultlessly for the past 6 years. Used on a daily basis as a liveaboard and never been touched let alone cleaned out.

 

Tom

 

My point is the all equipment must be accessible and not tucked out of the way

 

There are vent holes on some sump boxes which very occasionally need clean

 

Not like a boat builder who place an inverter / charger in cupboard which when the unit required looking at the cupboard had to be removed more than two hours work just to remove the cable termination cover

 

Season's Greeting

 

Keith

[RD1]

Our shower pump is a standard triple headed diaphragm pump, normally used for pressurised water delivery, so can run dry.

I have a pumpgard in front of the pump, this can easily be cleaned, and it traps hair, gunge and seeds that we have picked up on our shoes and clothes, that drop off when you are visiting the heads.

The pump is 30 years old, on the original diaphragm, and a couple of seasons ago, I decided to strip and clean the pump, waste of time, it was squeeky clean, no remnants of any gunge or hair either.

 

I don't like the sump pump idea, you have a wet box that collects unmentionables, some of this **** err material must be left behind to ferment and grow bacteria, and maybe some viruses, apart from the smell of stale drains, it can't be very healthy, more especially if it overflows.

 

With our system, if the drain pump can't handle the flow, time to clean the filter, by simply unscrewing the lid, and washing the stainless steel gauze, a three minute job. All the grey water is contained from the shower drain to the hull outlet, so no smells or risk of leaks.

Simple but very effective. As the pressure pump is pumping to an open outlet, it is using very little current, and the diaphragm is under the least stress, well 30 years on, still going. Frost protection involves putting a strong made up salt solution down the drain and pumping it through.

 

Best regards,

Richard

[Tom Richmond]

Is that right? I thought the 12v fridges were just 240v models with the compressor changed, the shell remains unchanged.

 

Steve

Have done a fair bit of research into low voltage fridges... On the surface they are just mains fridges with different compressors, but it gets a little more complex...

 

Until fairly recently it was the case that low voltage fridges were generally manufactured for the leisure market (Including boats, but largely caravans/Rvs) and the focus was on achieving maximum storage space in a small footprint, therefore sacrificing insulation, and subsequently efficiency. The assumption being that caravans are plugged in while at a site, and then charging from the engine while being towed, and for the boat market, that we cruise daily, therefore charging the batteries.

 

More recently however, with a rise in liveaboards, and with a shift in power generation caused by advances in solar technology, as well as an environmentally driven shift in our approach to power consumption, low voltage fridge manufacturers are producing much better insulated and therefore more efficient models. Most noteably there are a series of top loading fridges being manufactured for the off-grid market (eg "sundancer"), but also modern domestic models are much more efficient, and it no longer seems to be the case that a mains A+++ massively outperforms equivalent low voltage models. In fact I have read a few studies which show running a mains fridge through an inverter to be around 60% as efficient as a modern low voltage unit, though of course there are the cost and availability factors to consider as well.

 

I think I am going to go with an undercounter model from inlander. Probably a fridge freezer. As a point of note, all of the inlander fridges seem to be 12/24v, so my initial mistake in this thread becomes irrelevant.

[Tom Richmond]

 

My point is the all equipment must be accessible and not tucked out of the way

 

Keith

This!

 

Super valuable advice. Someone recently encouraged me to install all lining, bulkheads, fitted storage, etc, before running any services. That way if a break in a pipe, or a cut out panel is required to access anything, it will be created during installation.

 

It is doubtful that I will do this, as I think the benefits of having lights, as well as heating, while I continue with my fit-out outweigh the negatives. I also have a pet hate for plumbing, which stems from the horrible positions one must twist oneself into in order to access most pipe runs, and I am really looking forward to doing it when it is all easy access.

 

The point remains though, that everything must be accessible, this I intend to make paramount during this fit out.

 

For example, I will run the majority of electrics and plumbing beneath a lift out shelf, running the length of the gunwale (Dutch barge, with foot deep gunwales). The edge of the hull curves in to meet the floor, where I will have a small 'riser' like a skirting board, topped off with this shelf, so the majority of runs will be easily accessible for the entire length of the boat.

 

Steel frames make running cables up and down the walls tricky, and similarly lengthways along the roof, so lighting circuits will run along the top edges of the walls, with spurs running across the ceiling between frames where required. I plan to create a small channel behind a wooden trim in these top corners for cable. This wooden trim being easily removeable. This trim will also act as a curtain pelmet, will incorporate a way of hanging or fixing at any point (much like picture rails in victorian house, whether it's temporary hanging of washing, or permanently mounting a piece of artwork, it's always good to be able to hook stuff up safely and securely) and will have a piece of lighting track beneath it, so I can easily have a light wherever I like.

 

These are the plans at least...

Edited December 23, 2016 by Tom Richmond

[ditchcrawler]

Have done a fair bit of research into low voltage fridges... On the surface they are just mains fridges with different compressors, but it gets a little more complex...

 

Until fairly recently it was the case that low voltage fridges were generally manufactured for the leisure market (Including boats, but largely caravans/Rvs) and the focus was on achieving maximum storage space in a small footprint, therefore sacrificing insulation, and subsequently efficiency. The assumption being that caravans are plugged in while at a site, and then charging from the engine while being towed, and for the boat market, that we cruise daily, therefore charging the batteries.

 

More recently however, with a rise in liveaboards, and with a shift in power generation caused by advances in solar technology, as well as an environmentally driven shift in our approach to power consumption, low voltage fridge manufacturers are producing much better insulated and therefore more efficient models. Most noteably there are a series of top loading fridges being manufactured for the off-grid market (eg "sundancer"), but also modern domestic models are much more efficient, and it no longer seems to be the case that a mains A+++ massively outperforms equivalent low voltage models. In fact I have read a few studies which show running a mains fridge through an inverter to be around 60% as efficient as a modern low voltage unit, though of course there are the cost and availability factors to consider as well.

 

I think I am going to go with an undercounter model from inlander. Probably a fridge freezer. As a point of note, all of the inlander fridges seem to be 12/24v, so my initial mistake in this thread becomes irrelevant.

Do you mean these http://www.sundanzer.com/if so are they available in the UK?

 

If so its slightly more than I wanted to pay https://www.amazon.com/SunDanzer-DCRF134-Solar-Freezer-Refrigerator/dp/B008MA4HNG%3FSubscriptionId%3DAKIAI6CQ6I4LEAMY7HGQ%26tag%3Dcozit-20%26linkCode%3Dxm2%26camp%3D2025%26creative%3D165953%26creativeASIN%3DB008MA4HNG

Edited December 23, 2016 by ditchcrawler

[Tom Richmond]

Do you mean these http://www.sundanzer.com/if so are they available in the UK?

 

If so its slightly more than I wanted to pay https://www.amazon.com/SunDanzer-DCRF134-Solar-Freezer-Refrigerator/dp/B008MA4HNG%3FSubscriptionId%3DAKIAI6CQ6I4LEAMY7HGQ%26tag%3Dcozit-20%26linkCode%3Dxm2%26camp%3D2025%26creative%3D165953%26creativeASIN%3DB008MA4HNG

Yeah, those are the ones. I've not actually seen them available in the UK, though other companies are selling similar things. More than I want to pay too...

[ditchcrawler]

Yeah, those are the ones. I've not actually seen them available in the UK, though other companies are selling similar things. More than I want to pay too...

The problem I find is that the 12/24 fridges don't seem to require the same star/energy rating as 240 volt ones. so they quite things lake average load but you cant do a straight comparison.

[Justme]

Preliminary power audit is calling for around 600ah.

USB outlets (X8),

12v power outlets (x4 - these will be 24v to the outlet, with a step down converter located behind panel, with cigar socket output.)

 

 

 

 

 

Is that 600ah at 12v or 24v?

 

How many days usage is that & to what depth of discharge?

 

The usb & 12v outlets will use power all the time unless you switch the 24v feeds.

[Robbo]

May find this article interesting http://www.penguinfrigo.co.uk/assets/assets/PBO%20Fridge%20fitting.pdf

[Tom Richmond]

 

 

Is that 600ah at 12v or 24v?

 

How many days usage is that & to what depth of discharge?

 

The usb & 12v outlets will use power all the time unless you switch the 24v feeds.

600ah battery bank at 12v (so should read 300ah!) based on one days usage of roughly 150ah, rounded up to 200 for good measure and 3x capacity for battery bank, to allow for 80% - 50% discharge.

 

I will switch USB and 12v outlets. Would be sweet to find a way to do this automatically. The same way as jack plugs in guitars work, if anyone is familiar with these?

[ditchcrawler]

600ah battery bank at 12v (so should read 300ah!) based on one days usage of roughly 150ah, rounded up to 200 for good measure and 3x capacity for battery bank, to allow for 80% - 50% discharge.

 

I will switch USB and 12v outlets. Would be sweet to find a way to do this automatically. The same way as jack plugs in guitars work, if anyone is familiar with these?

How long do you expect to run your engine for each day to recharge them.

[Tom Richmond]

How long do you expect to run your engine for each day to recharge them.

If you read original post, you will see that boat has no inboard engine.

 

Charging will come from solar (~1.5kw), with generator backup during winter months.

[WotEver]

I will switch USB and 12v outlets. Would be sweet to find a way to do this automatically. The same way as jack plugs in guitars work, if anyone is familiar with these?

No automatically switched USB as far as I know. However there are plenty of switched outlets available such as this http://www.ecrater.com/p/23938067/highest-power-42-amp-usb-charger

[Justme]

600ah battery bank at 12v (so should read 300ah!) based on one days usage of roughly 150ah, rounded up to 200 for good measure and 3x capacity for battery bank, to allow for 80% - 50% discharge.

 

I will switch USB and 12v outlets. Would be sweet to find a way to do this automatically. The same way as jack plugs in guitars work, if anyone is familiar with these?

 

 

I think I am not getting what you have said.

 

You usage is 150ah at 12v.

You want 3 days usage to max 50% DOD

3 x 150 x 2 = 900ah@12v or 450ah at 24v.

 

With rounding up to 200ah@12v x 3 days x 2 (50%) = 1200ah@12v or the 600ah at 24v

 

So you are looking at 12 x 100ah 12v bats

 

Your solar will cope with 90% of your usage from March to October. Just needing top ups for those spells of crap weather that last a few days in a row.

 

Outside of that virtually all of your power will come from the genny.

 

What size charger will you use?

Edited December 24, 2016 by Justme

[ditchcrawler]

If I was using 150Ah per day I wouldn't bother about the few the USB outlets use 24/7 I don't know what the quiescent current of a 24 to 12 dropper is, but I wouldn't thought it much. as I said my usage is a third of that and I run a 24/1500 inverter 24/7 a cheap LEC mains fridge that is 15 years old, laptop, coffee machine (not used much, 6 cups per day) Christmas Lights, mains TV.

Edited December 24, 2016 by ditchcrawler

[Tom Richmond]

 

 

I think I am not getting what you have said.

 

You usage is 150ah at 12v.

You want 3 days usage to max 50% DOD

3 x 150 x 2 = 900ah@12v or 450ah at 24v.

 

With rounding up to 200ah@12v x 3 days x 2 (50%) = 1200ah@12v or the 600ah at 24v

 

So you are looking at 12 x 100ah 12v bats

 

Your solar will cope with 90% of your usage from March to October. Just needing top ups for those spells of crap weather that last a few days in a row.

 

Outside of that virtually all of your power will come from the genny.

 

What size charger will you use?

Not quite.

 

I am assuming one days usage. 150ah, rounded up to 200ah for good measure. Battery bank sized at 3 times that, to allow a 1/3 discharge. This assumes that the bank might not be fully recharged (say only 85%) and should not fall below 50% dod.

 

As you suggest, solar for 9 months of the year, genny rest of the time. In reality we use less power, the figures from the audit being maximum usage, so genny running every other day will probably suffice.

 

I have not spec'd a charger yet, but I gather 1/10th of bank capacity at 12v is the role of thumb. So a 60a 12v charger, not quite sure what the maths is for 24v...

 

I already live aboard at the same mooring, just on a smaller boat (300ah 12v, 350w solar, 30a charger) so am used to and comfortable with the charging regime. Doubling the size of our electrical capacity is what my audit calls for, and it feels right in terms of our usage, as we will have a bigger boat, and bigger family.

 

Happy Christmas everyone. Hope you all find the tiller pin you've always wanted in your stocking tomorrow!

[Justme]

Got it.

 

So you need solar each & every day as you cant go to two days with no charge as you will be at 33% soc.

 

Your heading for trouble / costly recharging.

 

For long term live in use you really need a few days of autonomy.

 

Even in summer you can get 2-5 days in a row of poor performance.

[Tom Richmond]

Got it.

 

So you need solar each & every day as you cant go to two days with no charge as you will be at 33% soc.

 

Your heading for trouble / costly recharging.

 

For long term live in use you really need a few days of autonomy.

 

Even in summer you can get 2-5 days in a row of poor performance.

Hmmm, ok. Makes sense. I will certainly take this into consideration. Thanks!