freebird
New member
is it ok to leave the battery charger on all the time . i have heard that thay are better left to discharge a bit and then recharge. i dont want to over charge them
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battery charging via shore power
- Thread starter freebird
- Start date
Mirelle
N/A
This is not the most helpful answer, but "depends on the quality of the battery charger". The sort of toy you use for a car battery should certainly NOT be left on; a good quality marine one can be left on for months with no harm done.
I hope an expert will pop up shortly and explain this properly!
<hr width=100% size=1>Que scais-je?
I hope an expert will pop up shortly and explain this properly!
<hr width=100% size=1>Que scais-je?
LadyInBed
Well-known member
or use the charger via a time switch
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tr7v8
Active member
My 2 batteries are charged by the following, I've a Carcoon type charger on the service battery this is on continuously and the start battery has a normal car charger set to low on a 7 day timeswitch for a couple of hours a week.
Been on near 14 months with no problems and they're always reasonably charged when I go there.
<hr width=100% size=1>Jim
Draco 2500
Been on near 14 months with no problems and they're always reasonably charged when I go there.
<hr width=100% size=1>Jim
Draco 2500
vyv_cox
Well-known member
I have a vehicle back home that has been garaged for 7 years. Batteries are charged by a cheap charger with a timer that comes on for two hours per week. On the rare occasions that we are at home it starts first time, every time.
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ex-Gladys
Well-known member
For 75AH and under you can get an Accumate battery optimiser. I use one for motorcycles, but checking them out they are availabel for up to 75AH. Plug in and forget. Cycles the battery, reduces sulphation
<hr width=100% size=1>Larry Botheras
Anderson 26 "Amber"
<hr width=100% size=1>Larry Botheras
Anderson 26 "Amber"
Birdseye
Well-known member
I use the Accumate type battery charger on my bikes, but there has been some debate amongst classic bike types as to whether this constant slight charge does eventaully b***er the batteries. Hasnt done so with my batteries - yet.
On the boat I use a Sterling multi stage job which is excellent - plug into shore power in a marina and use the fridge etc just as much as you like. Again it does a trickle charge for the batteries and this seems OK, though the fight for plug sockets at my club over winter ensures that the boat is not on trickle charge for long.
One things for sure - leaving a battery to go flat under its own internal leakage does no good at all, so I expect that a trickle charger is one of the least bad alternatives.
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On the boat I use a Sterling multi stage job which is excellent - plug into shore power in a marina and use the fridge etc just as much as you like. Again it does a trickle charge for the batteries and this seems OK, though the fight for plug sockets at my club over winter ensures that the boat is not on trickle charge for long.
One things for sure - leaving a battery to go flat under its own internal leakage does no good at all, so I expect that a trickle charger is one of the least bad alternatives.
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extravert
New member
A 3-stage charger is more suitable for long term charging, it senses what is going on and acts appropriately. Most 3-stage chargers are big and expensive, however...
RS sell a small low power 3-stage 12V charger. It's the smallest cheapest proper 3-stager that I can find. It only gives out 3A maximum, but is not harmed by connecting to large batteries, it self-limits its current output if required. If you are leaving it on long term it will get there eventually.
It costs approx £40 - catalogue number 301-4838.
I use one on my electrically-challenged boat. It's small and light, also good for a volumetrically and load-carryingly challenged boat.
<hr width=100% size=1>One day, I hope to own a real boat.
RS sell a small low power 3-stage 12V charger. It's the smallest cheapest proper 3-stager that I can find. It only gives out 3A maximum, but is not harmed by connecting to large batteries, it self-limits its current output if required. If you are leaving it on long term it will get there eventually.
It costs approx £40 - catalogue number 301-4838.
I use one on my electrically-challenged boat. It's small and light, also good for a volumetrically and load-carryingly challenged boat.
<hr width=100% size=1>One day, I hope to own a real boat.
ccscott49
Active member
Now that is a good bit of knowledge, thats very cheap, ideal for a marina based smallish boat.
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Trevethan
New member
I have a couple of chargers, a proper big sterliong job that powers a 400 amp bank that powers the domestics and starter.
I also have a little 90 amop that powers the electric heads. (I haven't gotten round to running a long cable all that way yet)
I have that hooked up to a small multistage charger from Halfrods, cost about £40 and its been connected for a couple of months without problems.
Its on trickle charge most of the time and it seem quite happy.
If you want to keep batteries topped up while not on boat, why not go solar? You can get cheapish 15 watt panels on ebay. 15 watts gives over an amp, though in winter in UK count on less!
But enough to keep up with self discharge and the odd bit of bilge pumping I'd guess.
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I also have a little 90 amop that powers the electric heads. (I haven't gotten round to running a long cable all that way yet)
I have that hooked up to a small multistage charger from Halfrods, cost about £40 and its been connected for a couple of months without problems.
Its on trickle charge most of the time and it seem quite happy.
If you want to keep batteries topped up while not on boat, why not go solar? You can get cheapish 15 watt panels on ebay. 15 watts gives over an amp, though in winter in UK count on less!
But enough to keep up with self discharge and the odd bit of bilge pumping I'd guess.
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tr7v8
Active member
The Carcoon type charger costs about £ 40 but their are some far cheaper ones about now. I think the Draper one came up quite well in a Classic car mags tests a little while ago. I brought mine for the TR7 after the first winter when the battery croaked, battery cost £ 40 which makes the charger cheap! Also means it starts everytime rather than mucking bout with jump leads.
This is mine and its now at £ 25!
<A target="_blank" HREF=http://www.race-technology.com/WebPage/Products/CHARGERS/ChargersMain.html>http://www.race-technology.com/WebPage/Products/CHARGERS/ChargersMain.html</A>
<hr width=100% size=1>Jim
Draco 2500
This is mine and its now at £ 25!
<A target="_blank" HREF=http://www.race-technology.com/WebPage/Products/CHARGERS/ChargersMain.html>http://www.race-technology.com/WebPage/Products/CHARGERS/ChargersMain.html</A>
<hr width=100% size=1>Jim
Draco 2500
freebird
New member
Thanks to everyone who replied, they were very useful
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ongolo
New member
Hi there,
I have a bit of an background in Electronics and related fields. My Boat is on the dry to be launched shortly. I lived in it now for two years while working on it.
Since that time I have run the Lights, up to 6 x 20W Halogen and 4 x 7W Flouresc. every day. I have two batteries of 105 Ah each.
Having shore power, I built variable voltage regulator using an LM317 that includes curent limiting and thermal limiting, so with other words you cannot blow the device.
I set the voltage to exactly 14Volt, which is as healthy as it can be for a battery, while one battery is OK, the other has now only a capacity of 10 minutes with all lights on. Identical treatment of both batteries shows that if a battery fails, it is not to say the wrong charger is to blame.
What I am going to do is to use a number of these LM317 in parallel with a typical output of 1.5A before currentlimiting sets in, and adjust them to different voltages so that at 12.5Vall 5 devices pull then at 13.6V only one still delivers which shuts down at 14V. This would deliver then 7.5A in total, should this not be enough, more 317 can be hooked up paralell. A simple Voltage Monitor for low battery voltage, could in addition to an alarm also cut in a relay to bypass the regulator and receive full current from whatever source there may be.
The best way to charge is about 10% of its capacity for 14 hours, that way no gasing occurs.
I have also halfway built a desulfator (not my design), but that gives high-voltage inductive spikes into the battery, but I am scared these spikes might also blow my Radar. So I am hesitant on this.
Again, one day next year, maybe I shall publish some articles about PC-board making (on board the vessel) and some simple devices anyone can make for his boat.
To come back to the LM317, it has only three legs, needs two or three resistors, and unless you apply more than 37V I think you will not be able to blow it.
If you experiment with new equipment or hobby electronics that requires 12V or less, the LM317 will also protect devices and itself against a full short.
regards ongolo
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I have a bit of an background in Electronics and related fields. My Boat is on the dry to be launched shortly. I lived in it now for two years while working on it.
Since that time I have run the Lights, up to 6 x 20W Halogen and 4 x 7W Flouresc. every day. I have two batteries of 105 Ah each.
Having shore power, I built variable voltage regulator using an LM317 that includes curent limiting and thermal limiting, so with other words you cannot blow the device.
I set the voltage to exactly 14Volt, which is as healthy as it can be for a battery, while one battery is OK, the other has now only a capacity of 10 minutes with all lights on. Identical treatment of both batteries shows that if a battery fails, it is not to say the wrong charger is to blame.
What I am going to do is to use a number of these LM317 in parallel with a typical output of 1.5A before currentlimiting sets in, and adjust them to different voltages so that at 12.5Vall 5 devices pull then at 13.6V only one still delivers which shuts down at 14V. This would deliver then 7.5A in total, should this not be enough, more 317 can be hooked up paralell. A simple Voltage Monitor for low battery voltage, could in addition to an alarm also cut in a relay to bypass the regulator and receive full current from whatever source there may be.
The best way to charge is about 10% of its capacity for 14 hours, that way no gasing occurs.
I have also halfway built a desulfator (not my design), but that gives high-voltage inductive spikes into the battery, but I am scared these spikes might also blow my Radar. So I am hesitant on this.
Again, one day next year, maybe I shall publish some articles about PC-board making (on board the vessel) and some simple devices anyone can make for his boat.
To come back to the LM317, it has only three legs, needs two or three resistors, and unless you apply more than 37V I think you will not be able to blow it.
If you experiment with new equipment or hobby electronics that requires 12V or less, the LM317 will also protect devices and itself against a full short.
regards ongolo
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philmarks
Member
Marine Battery chargers have the 12volt -ve side isolated from earth on mains side. I have read (Nigel Calder I think) that terrestrial chargers are not isolated in this way. The result can be anode and then hull corrosion in a steel boat.
Regards
Phil
<hr width=100% size=1>Rgds
Phil
Regards
Phil
<hr width=100% size=1>Rgds
Phil