All Electric?

[MtB]

1 minute ago, Up-Side-Down said:

I don't think there's ever been a need to be fair to Sterling ......

 

I'm pretty sure @Tony1 found the losses significant and quite troublesome. 

 

Maybe he will comment sooner or later.

[ditchcrawler]

One problem I see with a B2B is if you are using your starter battery and alternator to feed it to charge a 100% LifePo4 domestic bank, if your alternator is not providing sufficient current for the B2B it will discharge the starter battery until it reaches its cut off point. you may then be unable to start your engine . That ane the maximum current you B2B can charge at.

[Tony Brooks]

I wonder if any efficiency figures quoted by vendors are averages, which on LAs would tend to be low because of the time running at low currents, so less heating. As LIs will take as much current as you can provide, I would expect an average efficiency to be lower, more heating.

Edited November 11, 2023 by Tony Brooks

[wakey_wake]

11 minutes ago, Up-Side-Down said:

So I think you've just worked yourself round to a hybrid LA/LiFePO4 set up

I had been going that way, but the lack of time at LA = 14.4V is a problem.

(Sorry, forgot who I saw here point that out - maybe months ago on your timeline, but a week ago on mine.)

 

My thinking is going along these lines

• LA // LFP is good for simplicity, not losing 5~10% in the B2B, load dump safety and apparent (yes I agree seductive) ease of upgrade.
• LA -- B2B -- LFP looks nearly as simple if the LA is the starter; no domestic LA.
• Modern alternator control is greatly beneficial for either.
• Running 24V would be beneficial for diesel efficiency, but has disadvantages where lots of stuff is 12V.
• The engine would prefer to give 10~20kW mechanical but the rest of the system wants it a bit slower.
• A battery of 5 kW hr could be happy with at least 2.5kW electrical input. Prices are coming down enough that one could sensibly increase the bank size; that would allow weather-averaging across several days to let solar take much more of the load.
• A B2B with a power rating anywhere near what the engine and batteries prefer doesn't look sensible?
• Instead of belt driven automotive(like) alternators, a directly coupled permanent magnet alternator would be neat. They look a bit out of reach?
• (When the calorifier is cold, not all that waste heat is wasted! 5 kWh electrical generation probably leaves 30+ kWh of heat available.)

So a switchable LA --(parallel or B2B)-- LFP might be the answer for me.

1. Start the engine from LA. That's not a process I want a BMS getting involved in.
2. Check that voltages are compatible, in the sense of "what inrush current will I cause"?
3. Join LA to LFP, then ask the alternator to power up to suit engine conditions.
4. Bulk charge them in parallel, until the LFPs have had enough.
5. Tell the alternator to back off, then separate LA from LFP.
6. As suits electricity availability and LA maintenance schedule, top off the LA with a B2B or an ordinary charger running off the inverter.

I know that running a battery charger off an inverter is normally a weird thing to do. 😁

 

 

In my case, there are other complexities that I maybe ought to be ignoring. 🤔

The old bowthruster is dead and so are its 2*12V batteries. But the alternator is probably fine, so doing LA--(parallel or B2B)--LFP on that should give more charging and uses more of the hardware I already have. The long run of cable for that isn't a problem for electrical efficiency because the bulk charge isn't going to the BT; but having fuses both ends brings back the fear of a load dump into the LFP.

 

Using LFPs that have a BMS per 12V 100Ah unit, for me that indicates against running 24V. There is an extra level of balancing to be done, and one BMS sulk takes out twice as much capacity. If I wanted more than 3.5kW out, it would be different.

 

 

Stashing 30+ kW hr of heat is barely possible. GNU Units says "30 kW hr / (40 degC water_specificheat) = 645 kg", meaning if I were to use the ICE waste heat to raise a water tank from 30°C to 70°C (presumably to serve the under floor heating I haven't got) then it would be all of my water supply. This is near the border of craziness and it's not quite clear which side 😉 but it would heat the boat for about as long as the electricity lasted.

 

 

11 minutes ago, Up-Side-Down said:

: lots of YouTube videos out there to expand on the concept, largely dominated by a guy called Clark on a sailing boat called Temptress. He has an axe to grind/product to market (called a Bank Manager) and a lot of what he says is okay (to the point of being almost seductive).

 

Thanks - I've seen some of that and couldn't put my finger on exactly what I didn't like about it.

I'm not saying either is a "bad" product, but it doesn't seem to suit me in a different way to how Victron doesn't seem to suit me.

 

 

11 minutes ago, Up-Side-Down said:

However, when the BSS finally gets round to embracing lithium technology – and everything that goes with it – don't be too surprised if hybrid systems of a similar nature get more than frowned upon.

 

In the absence of an actual rule, or a suggestion of the reason for the rule, then I think the answer is to get moving now so the setup can be grandfathered in.

[Tony1]

1 hour ago, MtB said:

 

No I don't have a source other than having read it stated many times on here, unchallenged so probably true.

 

I think @Tony1 knows more than most on here about B2B chargers and their efficiencies.

 

 

 

To be honest Mike, there will be several members here who know more than I ever will about the way these things work, but I can give  a sort of layman's perspective after trying several different models of B2B over the last 2 years.

My impression is that there is some variation in efficiency of different units, at least based on what I've been able to measure with my rather limited understanding of the technical detail. 

The least impressive in my view were the Sterling BB1260s. They take in 60 amps, and in my use of a pair of them over a year or so, I found they put out about 48 amps at most, which is a 20% loss.

But even worse, every 15 minutes or so they would throttle back to very roughly half power (I think because they were getting too hot), and then they would put out about 28 amps. After about 10 minutes of this, they would then go back to 47 or 48 amps. So I would guess the average output over a day's cruise would be closer to 40 amps, which struck me as being a bit crap for a unit costing as much as they did.  

So putting aside the efficiency issue, I wasn't getting the consistent power output from those units that I was expecting.

Now in fairness they do have some brand new B2B models that are claimed to be much more efficient, so I wouldn't write off Sterling without having a long hard look at those new units.

The problem is they new ones seem to be pricier that the old BB1260's etc, so thats not great. 

The Sterling BB1230 takes in 30 amps, and I found mine put out about 27 or 28 amps for hour after hour, with no throttling down and less overheating- so that was much better, and they would suit a smaller/crappier alternator (of which I do have at least one).

But the 30 amp units are not half the price of the 60 amp units, so there is a sort of 'bang for buck' question with those. 

I eventually settled on Victron 30 amp B2Bs. 

I dont actually know how how efficient they are as I've never measured the input current for them, but they do seem to put out a consistent 28 or 29 amps- although I must say the body of the unit gets so hot that you cant keep your hand on it for more than 5 seconds, (unless you're more macho than I am). So I imagine they waste some heat, but since they dont have a fan, maybe it feels that way because they keep their heat within the unit more than the Sterling units did.

The Sterlings I think were much more more configurable than the victron units, and I did like the two 30 amp units, but the convenience of bluetooth control when you're at the tiller did win me over to Victron. 

As well as that sexy blue colour. 

 

Edited November 11, 2023 by Tony1

[Up-Side-Down]

3 minutes ago, wakey_wake said:

I had been going that way, but the lack of time at LA = 14.4V is a problem.

(Sorry, forgot who I saw here point that out - maybe months ago on your timeline, but a week ago on mine.)

 

My thinking is going along these lines

• LA // LFP is good for simplicity, not losing 5~10% in the B2B, load dump safety and apparent (yes I agree seductive) ease of upgrade.
• LA -- B2B -- LFP looks nearly as simple if the LA is the starter; no domestic LA.
• Modern alternator control is greatly beneficial for either.
• Running 24V would be beneficial for diesel efficiency, but has disadvantages where lots of stuff is 12V.
• The engine would prefer to give 10~20kW mechanical but the rest of the system wants it a bit slower.
• A battery of 5 kW hr could be happy with at least 2.5kW electrical input. Prices are coming down enough that one could sensibly increase the bank size; that would allow weather-averaging across several days to let solar take much more of the load.
• A B2B with a power rating anywhere near what the engine and batteries prefer doesn't look sensible?
• Instead of belt driven automotive(like) alternators, a directly coupled permanent magnet alternator would be neat. They look a bit out of reach?
• (When the calorifier is cold, not all that waste heat is wasted! 5 kWh electrical generation probably leaves 30+ kWh of heat available.)

So a switchable LA --(parallel or B2B)-- LFP might be the answer for me.

1. Start the engine from LA. That's not a process I want a BMS getting involved in.
2. Check that voltages are compatible, in the sense of "what inrush current will I cause"?
3. Join LA to LFP, then ask the alternator to power up to suit engine conditions.
4. Bulk charge them in parallel, until the LFPs have had enough.
5. Tell the alternator to back off, then separate LA from LFP.
6. As suits electricity availability and LA maintenance schedule, top off the LA with a B2B or an ordinary charger running off the inverter.

I know that running a battery charger off an inverter is normally a weird thing to do. 😁

 

 

In my case, there are other complexities that I maybe ought to be ignoring. 🤔

The old bowthruster is dead and so are its 2*12V batteries. But the alternator is probably fine, so doing LA--(parallel or B2B)--LFP on that should give more charging and uses more of the hardware I already have. The long run of cable for that isn't a problem for electrical efficiency because the bulk charge isn't going to the BT; but having fuses both ends brings back the fear of a load dump into the LFP.

 

Using LFPs that have a BMS per 12V 100Ah unit, for me that indicates against running 24V. There is an extra level of balancing to be done, and one BMS sulk takes out twice as much capacity. If I wanted more than 3.5kW out, it would be different.

 

 

Stashing 30+ kW hr of heat is barely possible. GNU Units says "30 kW hr / (40 degC water_specificheat) = 645 kg", meaning if I were to use the ICE waste heat to raise a water tank from 30°C to 70°C (presumably to serve the under floor heating I haven't got) then it would be all of my water supply. This is near the border of craziness and it's not quite clear which side 😉 but it would heat the boat for about as long as the electricity lasted.

 

 

 

Thanks - I've seen some of that and couldn't put my finger on exactly what I didn't like about it.

I'm not saying either is a "bad" product, but it doesn't seem to suit me in a different way to how Victron doesn't seem to suit me.

 

 

 

In the absence of an actual rule, or a suggestion of the reason for the rule, then I think the answer is to get moving now so the setup can be grandfathered in.

Love that verb!

[dmr]

21 minutes ago, ditchcrawler said:

One problem I see with a B2B is if you are using your starter battery and alternator to feed it to charge a 100% LifePo4 domestic bank, if your alternator is not providing sufficient current for the B2B it will discharge the starter battery until it reaches its cut off point. you may then be unable to start your engine . That ane the maximum current you B2B can charge at.

I've been looking into this recently as I am slipping slowly towards going lithium.

I think the Victron BTB sorts everything out, it monitors the charge voltage at the starter battery and controls the current taken to keep the charge voltage at a suitable value, but I still need to read more datasheets 😀.  It also has a remote enable that can be fed from the ignition, so with ignition off its standby current draw in tiny.

[wakey_wake]

43 minutes ago, MtB said:

That sounds more like it. Sterling coyly choose not to mention output power divided by input power for theirs, having had a brief scan of their specs.

Fair or no, it's an important piece of spec!

Voltage ranges in & out. Power throughput (which we get from "30A nominal 12V"), and the efficiency curve.

 

17 minutes ago, Tony Brooks said:

I wonder if any efficiency figures quoted by vendors are averages, which on LAs would tend to be low because of the time running at low currents, so less heating. As LIs will take as much current as you can provide, I would expect an average efficiency to be lower, more heating.

 

Like with engines & alternators, there will be a lot of factors. But not so many.

It's also much easier and faster to measure the efficiency across the curve.

 

There's also a line between coy marketing and not losing customers to a competitor because your product has corners cut which reduce the efficiency. Pushing DC-DC converters hard means higher current, which means bigger I²C losses in semiconductors and inductors of any size.

 

 

21 minutes ago, ditchcrawler said:

One problem I see with a B2B is if you are using your starter battery and alternator to feed it to charge a 100% LifePo4 domestic bank, if your alternator is not providing sufficient current for the B2B it will discharge the starter battery until it reaches its cut off point. you may then be unable to start your engine . That ane the maximum current you B2B can charge at.

 

Yes. If anything other than the glowplugs and starter motor are sucking on the engine start battery, then it's got to be carefully controlled and not fail in a way that leaves you stuck.

 

There is also some risk of overworking the starter's alternator, to the point of killing it. That's another reason to keep all that separate.

 

It's do-able though.

[Tony1]

17 minutes ago, dmr said:

I've been looking into this recently as I am slipping slowly towards going lithium.

I think the Victron BTB sorts everything out, it monitors the charge voltage at the starter battery and controls the current taken to keep the charge voltage at a suitable value, but I still need to read more datasheets 😀.  It also has a remote enable that can be fed from the ignition, so with ignition off its standby current draw in tiny.

 

The Sterling units also monitor the starter battery voltage, and they wont come on until the starter battery voltage rises above your set value.

Or you can set them to come on/off with engine ignition.

You can also set the starter battery voltage at which the B2B will switch off (for any B2B unit).

So what I do is to set that switch off voltage threshold higher than the unit's default value.

That means that  the B2B is switched off within a few seconds of the engine being switched off, so it prevents the B2B sucking loads of charge out of the lead acid batteries. My starter battery is still in great nick after well over 2 years of this regime. 

 

ETA- most people will see this as overkill, but as we all know, alternators run cooler at higher rpms (up to a point).

So what I also did was add a second 18 amp victron B2B unit, and I only switch that one on when I am moored up and doing an engine charge at a constant 1300rpm. 

That way I can squeeze an extra 18 amps of charge from the domestic alternator when I'm static charging.

I cant use that second 18 amp B2B when I'm cruising, because when I get to locks, or pass moored boats, the engine revs drop to tickover, and at tickover the domestic alternator cannot put out 30 amps plus 18 amps without it getting hotter than I am comfortable with. 

So when cruising I use a 30 amp B2B on each alternator, and I can add in the extra 18 amp unit when static. 

 

 

Edited November 11, 2023 by Tony1

[dmr]

10 minutes ago, Tony1 said:

 

The Sterling units also monitor the starter battery voltage, and they wont come on until the starter battery voltage rises above your set value.

Or you can set them to come on/off with engine ignition.

You can also set the starter battery voltage at which the B2B will switch off (for any B2B unit).

So what I do is to set that switch off voltage threshold higher than the unit's default value.

That means that  the B2B is switched off within a few seconds of the engine being switched off, so it prevents the B2B sucking loads of charge out of the lead acid batteries. My starter battery is still in great nick after well over 2 years of this regime. 

 

 

Times have changed, Victron stuff is just much much better and the prices are now competitive. I had a bit of Sterling stuff many years ago but am now convinced by Victron, its a horrible shade of blue but still not as ugly as the Sterling boxes 😀

[Tony1]

1 minute ago, dmr said:

Times have changed, Victron stuff is just much much better and the prices are now competitive. I had a bit of Sterling stuff many years ago but am now convinced by Victron, its a horrible shade of blue but still not as ugly as the Sterling boxes 😀

 

Indeed- I found the victron B2B prices to be competitive enough that I bought three of them. 

And the Sterling unts are horribly ugly in comparison. 

But still, I used two of their 30 amp B2Bs for well over a year, and they performed faultlessly.

I'm no lover of Sterling products after my own poor experiences with the BB1260 units, but I still think it would be worth at least looking at the new Sterling B2B units, they do claim good efficiency and it is possible they have learned lessons from the BB1260.  

But unless the Sterling B2Bs were significantly cheaper, I would go with Victron all day long. Why take the risk on Sterling, when you know there is a proven quality Victron product available? 

 

[wakey_wake]

1 hour ago, Tony1 said:

The least impressive in my view were the Sterling BB1260s. [...]

 

The Sterling BB1230 takes in 30 amps, and I found mine put out about 27 or 28 amps for hour after hour, with no throttling down and less overheating- so that was much better, and they would suit a smaller/crappier alternator (of which I do have at least one).

But the 30 amp units are not half the price of the 60 amp units, so there is a sort of 'bang for buck' question with those.

Hmm yeah...  it sounds like what I was saying ⏫ about pushing the thing too hard. If they'd branded the BB1260 as a BB1245 then it might have been a good product? So we're looking at "marketing amps".

 

I would love to see the insides of the BB1260 and BB1230!  Probably not going to happen.

 

 

1 hour ago, Tony1 said:

I eventually settled on Victron 30 amp B2Bs. 

[...] the body of the unit gets so hot that you cant keep your hand on it for more than 5 seconds, [... but ...] they dont have a fan, maybe it feels that way because they keep their heat within the unit more than the Sterling units did.

 

As a design choice, I do prefer passive cooling. It is going to cost more but less heat is good for efficiency and you're keeping things under control, rather than pushing the limit and then shoving a hurricane behind it to stop it melting...  until the spiders clog up the fan. Guess which end of my boat has most more spiders?

 

I don't dislike Victron kit, I just don't think the feature they offer are packaged in the combinations I want; and it's not an area where I find the expensive blue colour reassuring.

 

 

1 hour ago, Up-Side-Down said:

Love that verb!

 

Grandfathered? Yeah, I don't know a better word. Like the one in "verbing nouns is bad grammar".

 

 

1 hour ago, dmr said:

I think the Victron BTB sorts everything out, it monitors the charge voltage at the starter battery and controls the current taken to keep the charge voltage at a suitable value, but I still need to read more datasheets 😀.

 

57 minutes ago, Tony1 said:

The Sterling units also monitor the starter battery voltage,

[... I ] set that switch off voltage threshold higher than the unit's default value.

That means that  the B2B is switched off within a few seconds of the engine being switched off, so it prevents the B2B sucking loads of charge out of the lead acid batteries. My starter battery is still in great nick after well over 2 years of this regime.

 

With an old-regulator alternator, I think dragging the start battery's voltage down is the only way to make the alternator work hard enough to get that power?

 

In this context the starter & domestic are a split bank of LA like 👇, but not evenly split.

 

2 hours ago, wakey_wake said:

Suppose, in the absence of LiFePO4 just to simplify the conversation, one split an LA bank in two. They both get a bulk charge, then stop then engine and use one to power the absorption charge of the other. Possibly you want another short burst of engine to give a second bulk charge to the donor. (Next time, swap them.)

This is a bit weird and I've never seen it, but in theory it prevents sulphation by giving the 100%-ish charge often enough, and not heavily depleting the other half bank to do it. But without spinning the engine at negligible load for pointless hours.

 

Do none of the B2Bs do this?  I'm not sure, but I think the 4-switch topology makes bi-directional transfer little more expensive that uni-directional.

The starter is too small to take the domestic bank up to 14.4V after the engine stops, even if you wanted to.

But the domestic bank is plenty big enough to give the starter some after the engine stops.

 

Is that a missing feature, or do any of them do it?

Edited November 11, 2023 by wakey_wake
boat is not a triangle (most->more)

[dmr]

11 minutes ago, wakey_wake said:

 

With an old-regulator alternator, I think dragging the start battery's voltage down is the only way to make the alternator work hard enough to get that power?

 

 

 

The correct way to get a good charge from an alternator is to use an external controller. Historically this was an Adverc, plus a few others including Sterling, but recently the Wakespeed is becoming the way to go. These all require a small mod to the alternator.

The Sterling alternator to battery charger thing (that pulls the voltage down) was really intended as a last resort? when it was not possible to modify the alternator, (probably due to waranty concerns), it got quite popular but really is a case of a sledgehammer to crack a nut.

[Tony1]

 

8 minutes ago, wakey_wake said:

I would love to see the insides of the BB1260 and BB1230!  Probably not going to happen.

 

 

 

I still have one of each of those two units knocking around somewhere, as a sort of backup in case the victron units ever fail (although to be fair, you can buy those victron B2Bs on amazon with next day delivery). 

But I would be willing to sell them, so if your eagerness to investigate them is strong enough to part with a couple of hundred quid, you could get your wish. 

 

8 minutes ago, wakey_wake said:

 

I don't dislike Victron kit, I just don't think the feature they offer are packaged in the combinations I want; and it's not an area where I find the expensive blue colour reassuring.

 

 

I am definitely a fan of the blue colour. The B2B units are configurable enough, and have the features I need, and they are now as cheap as many other units (and so far they seem to me probably better designed and better quality than most)- so for me, it was an easy choice to make. 

 

8 minutes ago, wakey_wake said:

 

With an old-regulator alternator, I think dragging the start battery's voltage down is the only way to make the alternator work hard enough to get that power?

 

In my admittedly limited experience, I've found that when connected to lithium batteries, even with a lead acid 'feeder' battery in parallel, there is no problem persuading my alternators to put out their maximum rated current.

In my case, I've found the challenge to be reducing (or at least controlling) the current output from the alternators- which is where the B2Bs do such a good job. .

 

 

 

[MtB]

31 minutes ago, dmr said:

The correct way to get a good charge from an alternator is to use an external controller. Historically this was an Adverc, plus a few others including Sterling, but recently the Wakespeed is becoming the way to go.

 

I wonder if you, like me, find yourself wondering if user "wakey_wake" is connected with Wakespeed in any way.... 

 

 

[peterboat]

Most B 2 Bs seem to be used on campervans, the smart alternators fitted to modern Van's won't allow bi directional VSRs to work, thankfully my campervan is old technology and a cheap and efficient VSR does the job nicely 

[IanD]

B2B/inverter/charger efficiency -- especially anywhere but the "maximum efficiency" point -- is something that all the suppliers keep quiet about, not just Sterling...

 

Here's what my all-Victron setup is doing right now while charging from shoreline -- not all the numbers add up, but from what I've seen it seems that the "AC loads" is where the charger/inverter losses get lumped in, here they're about 11% of input power. The only figure Victron quote for the Quattro 48/10000 is peak efficiency of 96% when inverting, but without saying what power level this is at... 😞

 

 

Edited November 12, 2023 by IanD

[wakey_wake]

10 hours ago, Tony1 said:

I still have one of each of those two units knocking around somewhere, as a sort of backup in case the victron units ever fail (although to be fair, you can buy those victron B2Bs on amazon with next day delivery). 

But I would be willing to sell them, so if your eagerness to investigate them is strong enough to part with a couple of hundred quid, you could get your wish.

 

I will need B2B and alternator regulator units at some point.

 

I only wanted to see inside the Sterlings for this reason: my suspicion is they'll be remarkably similar inside. Maybe the BB1230 will be a bit lighter than the BB1260 in places, but if a company discovers that it has over-advertised a product line then it makes sense for the next product in the line to be a bit over-engineered.  That puts both BB1260 and BB1230 at about a "BB1245" kind of size.

 

However, neither my ego nor my wallet are large enough to shell out for ownership of yours. 😁

Thanks for the offer.  Photos would be very welcome but I understand that taking the lid off could reduce their value to you.

 

 

10 hours ago, Tony1 said:

I am definitely a fan of the blue colour. The B2B units are configurable enough, and have the features I need, and they are now as cheap as many other units (and so far they seem to me probably better designed and better quality than most)- so for me, it was an easy choice to make. 

 

In my admittedly limited experience, I've found that when connected to lithium batteries, even with a lead acid 'feeder' battery in parallel, there is no problem persuading my alternators to put out their maximum rated current.

In my case, I've found the challenge to be reducing (or at least controlling) the current output from the alternators- which is where the B2Bs do such a good job. .

 

I'm sure the Victrons are good kit, where they meet one's needs. The professional electronics engineer I talk to has a lot of respect for them and reckons they're fairly bulletproof (electrically!). He also thinks they're worth the money / wouldn't try to build something like and expect to save money.

 

Info about the voltage-current curve of the alternator is useful, thanks. Did I infer correctly that you have old-style regulators?

What I'm hearing is that the regulation is still pretty strong, so I was wrong about needing to pull the voltage down to get the power. However, smart regulation will still be better.

 

11 hours ago, dmr said:

The correct way to get a good charge from an alternator is to use an external controller. Historically this was an Adverc, plus a few others including Sterling, but recently the Wakespeed is becoming the way to go. These all require a small mod to the alternator.

It seems clear that old-style regulators only compete on price & being already there.

(I could use a more descriptive name? I'm sure US English would call them dumb regulators, but neither of these things will speak; I dislike the assumption that dumb means stupid)

 

I didn't realise it was a small mod. Do the external regulators drive the field directly?

I thought they provided a PWM input, and an onboard regulator amplified that perhaps with some other feedback inputs such as over-voltage shutdown.

 

 

10 hours ago, MtB said:

I wonder if you, like me, find yourself wondering if user "wakey_wake" is connected with Wakespeed in any way....

 

Nice spot but no, that's a coincidence. 😁

 

I hadn't heard of the Adverc and it sounds like that has missed the boat. 😉

I started hearing about B2B in the context of stealth campers and "split charge relays won't charge your domestic bank", then started learning a bit about smart alternators.

I heard of the Wakespeed on here. I see it's produced by the company that does the Battleborn batteries and my impression is that they're working hard to produce good kit. Competition for Victron? Perhaps small enough to be bought up by Victron when they start to eat market share? That's not my concern.

 

I can be open about what I'm up to here -

 

I look at the prices of these boxes, I compare to the knockoffs (at least of MPPTs and inverters) which aren't sufficiently tested and tend to melt, and I look at the prices of the "generic" unboxed electronics modules which are banged out probably in violation of somebody's design copyright...  all I want is a few tens of Amps of DC-DC converter. At ebay module prices that's £50, but bring your own enclosure and a control interface.

 

So I want a control interface for B2B-ing and another for MPPT-ing. That shouldn't be so hard, and there will be a lot in common.

Then I think I want to stack up a modular array of DC-DC converters that shovel the coulombs as directed, and report back enough information to keep them under control.

 

From any of the commercial offerings I'm happy to steal ideas for features and heed warnings about what doesn't work. I don't need to reverse engineer any of these things, I don't expect to find anything both innovative and accessible. I don't think I want to bother implementing a CANbus stack and making it compatible, because I don't expect to have anything that would talk to it. RS485 looks adequate for me, but it's just networking and software.

 

Do I want to start a company that competes against the incumbents? No thanks.

Running a company looks like hard work: not enough customers to pay, or too many customers to give good service. Or having employees, which is a whole other set of problems.

 

I will probably end up with a boat full of unusual kit, and y'all will warn me that I'm decreasing the resale value / laugh when the kit fails.

Would I make it open source hardware, in the hopes that other folks would help me test it? Quite likely.

 

Would I run a company providing some consultancy on such OSHW? Maybe but not yet.

 

 

9 hours ago, peterboat said:

Most B 2 Bs seem to be used on campervans, the smart alternators fitted to modern Van's won't allow bi directional VSRs to work, thankfully my campervan is old technology and a cheap and efficient VSR does the job nicely 

 

It's good to share the hardware market for 12V and 24V stuff. It will bring more choice, better prices and better access to service.

[dmr]

14 minutes ago, wakey_wake said:

 

Info about the voltage-current curve of the alternator is useful, thanks. Did I infer correctly that you have old-style regulators?

What I'm hearing is that the regulation is still pretty strong, so I was wrong about needing to pull the voltage down to get the power. However, smart regulation will still be better.

 

It seems clear that old-style regulators only compete on price & being already there.

(I could use a more descriptive name? I'm sure US English would call them dumb regulators, but neither of these things will speak; I dislike the assumption that dumb means stupid)

 

I didn't realise it was a small mod. Do the external regulators drive the field directly?

I thought they provided a PWM input, and an onboard regulator amplified that perhaps with some other feedback inputs such as over-voltage shutdown.rvice.

 

 

External regulators drive the field (rotor) directly but in parallel with the existing internal regulator so they can increase the field current and hence output voltage but can't reduce it.

For this to work an extra wire has to be solderred on to one of the brush connections.

 

The Wakespeed needs to reduce the output to go into a flat or disabled mode, essential for lithium, so this needs the internal regulator removing, a wire solderred on, and probably a new ground connection fitting. I think it also needs the diode trio disabling, so a more complicated alternator mod.

 

The adverc was able to raise the alternator voltage and provide temperature compensation, it was a good device but is now rather outdated. If you don't need the Wakespeed functionality then Advercs can sometimes be found on eBay.

 

Wakespeed are a very small company set up to comercialise an Arduino project and only have one significant product. It might be good (for us) if Victron took them over, though their controller is already quite well integrated into the Victron scheme of things.

[IanD]

26 minutes ago, dmr said:

 

External regulators drive the field (rotor) directly but in parallel with the existing internal regulator so they can increase the field current and hence output voltage but can't reduce it.

For this to work an extra wire has to be solderred on to one of the brush connections.

 

The Wakespeed needs to reduce the output to go into a flat or disabled mode, essential for lithium, so this needs the internal regulator removing, a wire solderred on, and probably a new ground connection fitting. I think it also needs the diode trio disabling, so a more complicated alternator mod.

 

The adverc was able to raise the alternator voltage and provide temperature compensation, it was a good device but is now rather outdated. If you don't need the Wakespeed functionality then Advercs can sometimes be found on eBay.

 

Wakespeed are a very small company set up to comercialise an Arduino project and only have one significant product. It might be good (for us) if Victron took them over, though their controller is already quite well integrated into the Victron scheme of things.

The Wakespeed just needs the internal regulator removing/bypassing and the brushes connecting directly, so it controls the field current. As you say this is essential for LFP batteries if you don't want to risk overcharging and disconnection by the BMS.

[dmr]

1 hour ago, IanD said:

The Wakespeed just needs the internal regulator removing/bypassing and the brushes connecting directly, so it controls the field current. As you say this is essential for LFP batteries if you don't want to risk overcharging and disconnection by the BMS.

 

A Wakespeed is in my list for some electrical upgrades this winter in readiness for a lot of lithium so I have been swotting up.

Wakespeed prefer the "P type" arrangement (is this the correct terminology or am I thinking of transistors 😀) so I think the regulator needs removing and the diode feed to the top brush also has to go, replaced by an external wire, plus a direct ground connection to the bottom brush is then needed.

This is different to the Adverc where you just connect a wire to the bottom (negative) brush.

 

[IanD]

Just now, dmr said:

 

A Wakespeed is in my list for some electrical upgrades this winter in readiness for a lot of lithium so I have been swotting up.

Wakespeed prefer the "P type" arrangement (is this the correct terminology or am I thinking of transistors 😀) so I think the regulator needs removing and the diode feed to the top brush also has to go, replaced by an external wire, plus a direct ground connection to the bottom brush is then needed.

This is different to the Adverc where you just connect a wire to the bottom (negative) brush.

 

IIRC the Wakespeed works with both P and N type alternators, but a different wiring harness is needed for the two cases. A floating ground alternator can use either type.

[PeterF]

I have my Wakespeed ready for install and I am using an N type harness, this is on Beta 43 with the ISKRA 175A alternator. " new wires direct to the brushes, one will connect to the B terminal and the other the Wakespeed harness and from the Wakespeed to ground. The ISKRA is N type, but with the Wakespeed you could choose to go to P type as both brushes need new connections.

 

Wakespeed have been bought by Dragonfly Energy who sell the Battleborn range of lithium batteries.

 

There is a new kid on the block, the Zeus alternator regulator which has a good group of experts (including Rod Collins of Marine How To) and a large alternator manufacturer (ARCO) behind it. More complex than the Wakespeed, with Bluetooth, both battery and alternator current shunts, lots more control inputs. See 

https://arcomarine.com/products/arco-zeus-high-energy-alternator-regulator

[dmr]

5 minutes ago, IanD said:

IIRC the Wakespeed works with both P and N type alternators, but a different wiring harness is needed for the two cases. A floating ground alternator can use either type.

 

Wakespeed mention the harness option in their publicity stuff but the installation instructions very much favour the P system.

Their justificatiin is:... if the external wire shorts to ground then an N system gives full alternator output and an overvoltage, a short on a P just blows a fuse.

Thats good enough for me, especially as this did happen on our Adverc system though I spotted it in time.

 

Is a floating ground alternator not one where the stator is not grounded to the case????

9 minutes ago, PeterF said:

I have my Wakespeed ready for install and I am using an N type harness, this is on Beta 43 with the ISKRA 175A alternator. " new wires direct to the brushes, one will connect to the B terminal and the other the Wakespeed harness and from the Wakespeed to ground. The ISKRA is N type, but with the Wakespeed you could choose to go to P type as both brushes need new connections.

 

Wakespeed have been bought by Dragonfly Energy who sell the Battleborn range of lithium batteries.

 

There is a new kid on the block, the Zeus alternator regulator which has a good group of experts (including Rod Collins of Marine How To) and a large alternator manufacturer (ARCO) behind it. More complex than the Wakespeed, with Bluetooth, both battery and alternator current shunts, lots more control inputs. See 

https://arcomarine.com/products/arco-zeus-high-energy-alternator-regulator

 

That looks good, I will find out more. And a very similar price to the Wakespeed.

Its a shame that the Wakespeed did not continue as an open source project.

I am concerned that there are now a lot of alternator controllers fighting for what must be quite a small market, will they all survive?

[PeterF]

20 minutes ago, dmr said:

 

Wakespeed mention the harness option in their publicity stuff but the installation instructions very much favour the P system.

Their justificatiin is:... if the external wire shorts to ground then an N system gives full alternator output and an overvoltage, a short on a P just blows a fuse.

Thats good enough for me, especially as this did happen on our Adverc system though I spotted it in time.

 

Is a floating ground alternator not one where the stator is not grounded to the case????

 

That looks good, I will find out more. And a very similar price to the Wakespeed.

Its a shame that the Wakespeed did not continue as an open source project.

I am concerned that there are now a lot of alternator controllers fighting for what must be quite a small market, will they all survive?

 

I agree on the P type is probably better if a field wire short occurs but I spotted this after I had purchased the N type Harness and understand that I could do the alternator whatever flavour I wanted. I have double insulated the field wires and should bring them out of the back through the plastic cover rather than metal case.

 

Wakespeed programming has improved a lot with the Android app but you still need a USB cable connection so no I-Phone app as they do not have that facility. This was always the bug bear with them. The Zeus may give them the impetus to sort out their Bluetooth. I think that the market is going to increase with lithium uptake increasing.

 

 

Edited November 12, 2023 by PeterF