What am I missing out on?

[RupertW]

The alternator charging thread reminded me that I am still baffled by the intelligent charging systems, vsrs or whatever and super battery banks.

I'm still on the two batteries with circular or handle isolator switches and a halfords charger when I'm in marinas and have almost never had any issues with the set up. Apart from one long Biscay crossing where the auto helm took a lot of juice so the engine needed to run for 1 hour in 6 it's always been fine.

In my current boat we charge up the batteries in the Marina at the beginning of the week, though they usually don't need much, then live at anchor for the rest using the engine when needed to get in and our of bays or light winds on passage.

Are better charging systems for those rare occasions where they would give you, say, 1 hours engine run in 12 hours not 6, or am I missing something bigger here?

 

[ianj99]

The alternator charging thread reminded me that I am still baffled by the intelligent charging systems, vsrs or whatever and super battery banks.

I'm still on the two batteries with circular or handle isolator switches and a halfords charger when I'm in marinas and have almost never had any issues with the set up. Apart from one long Biscay crossing where the auto helm took a lot of juice so the engine needed to run for 1 hour in 6 it's always been fine.

In my current boat we charge up the batteries in the Marina at the beginning of the week, though they usually don't need much, then live at anchor for the rest using the engine when needed to get in and our of bays or light winds on passage.

Are better charging systems for those rare occasions where they would give you, say, 1 hours engine run in 12 hours not 6, or am I missing something bigger here?

Lucky you - no power issues! So no need to change anything.

However the more sophisticated systems are indeed aimed at maximising the alternator output from as low as rpm as possible, and charging the batteries to as close to 100% as possible.
The automotive system found on marine engines is not designed to do either, since motor vehicles never rely on battery power except for starting.

Many boat owners have power problems and often misguidedly install more battery capacity, without considering how they are going to replenish the charge. In fact their problems are often due to:
a) under charged batteries
b) batteries damaged (ie their life has beend shortened, often drastically) by being under charged, discharged too far, or left partially discharged for long periods.

You could, should you wish to cut down on engine run time, fit a digital regulator to replenish your batteries more quickly, and possibly fit a smaller pulley to the alternator so it can produce a higher output for the same engine revs.

 

[prv]

Ian's answer addresses the smart chargers; the point of VSRs is largely to avoid having to (remember to) switch over the big switch when you start and stop the engine. Seems a small thing, but I do like the fact that all I have to do is switch on the engine panel (what used to be the key) and then press the start button. And then switch the panel off and pull the stop handle next to it. The battery connections get switched in and out automatically as required.

(I have the steaming light come on and off with the engine as well. The nav light switch controls this via a relay, as well as the instrument and compass lights.)

Pete

 

[ianj99]

Ian's answer addresses the smart chargers; the point of VSRs is largely to avoid having to (remember to) switch over the big switch when you start and stop the engine. Seems a small thing, but I do like the fact that all I have to do is switch on the engine panel (what used to be the key) and then press the start button. And then switch the panel off and pull the stop handle next to it. The battery connections get switched in and out automatically as required.

(I have the steaming light come on and off with the engine as well. The nav light switch controls this via a relay, as well as the instrument and compass lights.)

Pete

Like the steaming light idea.

I drive my split charge relay from the alternator aux output so no vsr needed.
(I can switch it off if I ever I want all the juice to charge to engine battery first)

Ian

 

[RupertW]

Thanks for the answers so far.

Steaming and nav lights sounds good, although I find the idea of burning lights during the day very weird. I guess even my charging arrangements should comfortably cope.

We are so used to isolator switches that the VSR doesn't sound like it will add much for us, especially as the engine buzzer sounds very loudly as a reminder once it's battery is unisolated and the engine not running.

But the digital charger does sound like something I should look at if I want to do longer distance voyaging again where auto helms and lights take up more power, and fuel gets more precious. Not being able to use the fridge would be the main downside of more efficient battery charging, I think.

My fridge runs straight off an engine pulley at the moment which is a PITA in the marina but will probably just buy a portable ice maker that runs off the mains to keep it cool as those seemed to have dropped to about £100. Apart from that it's just cabin lights and the water system pumps that run now and again.

 

[nigelmercier]

(I have the steaming light come on and off with the engine as well. The nav light switch controls this via a relay, as well as the instrument and compass lights...

Thank you, you've just given me another outlet on my switch panel.

 

[prv]

Steaming and nav lights sounds good, although I find the idea of burning lights during the day very weird.

You misunderstand.

I have the engine circuit energise a relay. The engine is running, so the small current used in the coil is no problem. During the day, that's all that happens; no lights are lit. The switch side of the relay is fed from the nav light circuit, but that circuit is switched off.

As it gets dark, I turn on the nav lights. This powers the bicolour and stern lights directly, and also the compass and instrument lights. It also, as mentioned, supplies the switch side of the relay, so if the engine is running then the steaming light comes on, and if it's not running then it doesn't.

Not that any of this has anything to do with your original question about charging

As an aside, I believe commercial ships do run their nav lights full time. Bulbs last longer that way, and they have oodles of power from their main generators.

Pete

 

[prv]

Thank you, you've just given me another outlet on my switch panel.

Only thing to be aware of is that you won't be able to run your engine for battery charging on a night passage, without showing the wrong lights or taking out a fuse etc. I've never needed to run KS's engine just for charging, so it doesn't bother me, but it was pointed out by others last time I mentioned it. If I did need to, the connection to the relay is a spade terminal that's easy to get at, so it's still possible.

Pete

 

[RupertW]

Only thing to be aware of is that you won't be able to run your engine for battery charging on a night passage, without showing the wrong lights or taking out a fuse etc. I've never needed to run KS's engine just for charging, so it doesn't bother me, but it was pointed out by others last time I mentioned it. If I did need to, the connection to the relay is a spade terminal that's easy to get at, so it's still possible.

Pete

I now understand the relay bit, but on the point above I remember begin ticked off during my YM exam because I had the engine on in neutral to keep the lights going as I sailed up the Hamble at night to demonstrate I could berth in a tidal stream under sail. His gripe was that I should have had the steaming light on as I could have used the engine just by moving the throttle so had no right to expect sailing privileges. So with engine on for charging you should have steaming light on, therefore no nee to disconnect the relay.

Now we really are onto thread drift.

 

[prv]

His gripe was that I should have had the steaming light on as I could have used the engine just by moving the throttle

Afraid he was wrong then. Steaming light indicates being "propelled by machinery". You're not being propelled until you put it in gear. This isn't just my reading, it seems to be the standard consensus and this is the first time I've heard of someone suggesting otherwise.

Pete

 

[RupertW]

Afraid he was wrong then. Steaming light indicates being "propelled by machinery". You're not being propelled until you put it in gear. This isn't just my reading, it seems to be the standard consensus and this is the first time I've heard of someone suggesting otherwise.

Pete

Perhaps John Morris UK could come back on this one? I was feeling quite chirpy about leaving the steaming light off until the YM examiner told me otherwise but frankly I took his interpretation of the rules as above mine.

 

[prv]

I could have used the engine just by moving the throttle so had no right to expect sailing privileges.

As well as not meeting the letter of the rules (presumably he thought it met the spirit), this doesn't even make logical sense. I used to keep my engine in forward gear when it was stopped, to prevent the gearbox from rotating. The engine starts quite happily in gear, and will immediately give drive. So I could have used the engine just by pressing the start button, and by your man's reasoning I should have sailed everywhere with the steaming light on because I might have used the engine.

Pete

 

[Stu Jackson]

Not intended as thread drift: Have you considered installing a battery monitor so you know the condition of your batteries?

 

[RupertW]

Not intended as thread drift: Have you considered installing a battery monitor so you know the condition of your batteries?

That's not thread drift - it's taking me right back to my original post trying to understand the advantages of being a bit less basic with my electrics.

I confess I've owned boats for up to 8 years and never replaced the batteries the boat came with. There's a voltmeter on panel so I can see that for each battery so what does a battery monitor do? Actually I'm being lazy now, I'll google it now you have mentioned that a monitor might help. Im presuming battery condition means it's ability to take charge and deliver the AMp hours in the label.

 

[nigelmercier]

His gripe was that I should have had the steaming light on as I could have used the engine just by moving the throttle ...

Utter tosh! One could then argue then that you should have the steaming light on, or a triangle hoisted, at all times: as you could use the engine just by starting it.

Under power? What me? Nah, just charging the batteries mate!

 

[Bosun Higgs]

As an aside, I believe commercial ships do run their nav lights full time. Bulbs last longer that way, and they have oodles of power from their main generators.

Pete

probably more to do with sloppiness / lazyness as anyone who has ever run a factory will suggest. getting employees to switch things off is a never ending PITA.

 

[prv]

probably more to do with sloppiness / lazyness as anyone who has ever run a factory will suggest. getting employees to switch things off is a never ending PITA.

Ah, but in your factory you get a bill at the end of the month, so it matters. The extra fuel used in a generator to power a bulb must be undetectable as a fraction of the fuel used to push 100,000 tons of container ship through the water.

The permanent crew on Stavros (who are mostly commercial shipping people) discourage the turning off of lights, eg in storage spaces, the tank tops, etc. I was once told it's because the chief engineer likes his generators to have a constant minimum load when things like the galley, heating, and most accommodation lighting is turned off at night.

Pete

Edited to add - someone once turned off the focsle light as they left, and nobody including the bosun knew where the switch was to turn it back on again. Until then the light had always been on, so no need to use the switch.