Battery charging on a timer, or not?

Thepipdoc

Thepipdoc

Well-Known Member
Joined
13 Jun 2009
Messages
937
Location
Torquay, Devon/River Dart
Visit site
I currently leave my battery charger on 24/7.
When I'm not on-board I have a fridge/freezer running and that's about it.

Would I be better off running the battery charger through a timer switch, say for 2 hours per day or is it better to leave the charger running 24/7.
(All batteries are new this year and I think all 3 are 185ah)
 
Thepipdoc said:
I currently leave my battery charger on 24/7.
When I'm not on-board I have a fridge/freezer running and that's about it.

Would I be better off running the battery charger through a timer switch, say for 2 hours per day or is it better to leave the charger running 24/7.
(All batteries are new this year and I think all 3 are 185ah)
Click to expand...

Turn the charger off, leave it for some time, turn it on and check if it goes through the correct charge sequence, and time to do to it.

If it does goes through the sequence okay, you can set a timer to allow for that cycle time, and leave it on timer. Cycling to a high voltage for a short time is good, minutes, not hours though,

If it does not go through the correct cycle, or runs on high voltage for a long time, it may be better of leaving it on 24/7.

But try it to see what you get first.

Brian
 
Thepipdoc said:
I currently leave my battery charger on 24/7.
When I'm not on-board I have a fridge/freezer running and that's about it.

Would I be better off running the battery charger through a timer switch, say for 2 hours per day or is it better to leave the charger running 24/7.
(All batteries are new this year and I think all 3 are 185ah)
Click to expand...

I have left my Sterling 30 battery charger switched on for about 8 years now and the 4 boat batteries are still fully servicable, always starting the engines and with no evidence of a reduced charge cycle time. I do however, regularly check the electrolite levels as this does tend to bubble away. I am sure there are many who would question this decision but there is 8 years of experience there and I have known of many others who have not been able to make batteries (that are not always on charge) last that long.
 
Thepipdoc said:
I currently leave my battery charger on 24/7.
When I'm not on-board I have a fridge/freezer running and that's about it.

Would I be better off running the battery charger through a timer switch, say for 2 hours per day or is it better to leave the charger running 24/7.
(All batteries are new this year and I think all 3 are 185ah)
Click to expand...

With the fridge/freezer left on I would leave the charger on full time otherwise you will be cycling the batteries by around 10% every day and I would think this would shorten their life. This assumes a smart 3 or more stage charger.

With the fridge tuned off two hours a day would be fine, although I still leave mine on 24/7 even though everything is turned off.
 
Thepipdoc said:
I currently leave my battery charger on 24/7.
When I'm not on-board I have a fridge/freezer running and that's about it.

Would I be better off running the battery charger through a timer switch, say for 2 hours per day or is it better to leave the charger running 24/7.
(All batteries are new this year and I think all 3 are 185ah)
Click to expand...

Bernie are you saying that your fridge runs off 12v? Surely it's also 240v when shore power is available, which you have in DH? Making that assumption then it's just about your battery charger. Having previously run mine 24/7 when on a marina berth, I now only turn the chargers on when I'm on board. The problems of batteries running dry being the main consideration.

PS do you still want me to check yr anodes?
 
longjohnsilver said:
Bernie are you saying that your fridge runs off 12v? Surely it's also 240v when shore power is available, which you have in DH? Making that assumption then it's just about your battery charger. Having previously run mine 24/7 when on a marina berth, I now only turn the chargers on when I'm on board. The problems of batteries running dry being the main consideration.
Click to expand...

Good point ref fridge running off mains power. If that is the case the fridge probably didn't need mentioning in the OP and the two hours a day or even as you do, just when you visit the boat, would be fine.
 
longjohnsilver said:
Bernie are you saying that your fridge runs off 12v? Surely it's also 240v when shore power is available, which you have in DH? Making that assumption then it's just about your battery charger. Having previously run mine 24/7 when on a marina berth, I now only turn the chargers on when I'm on board. The problems of batteries running dry being the main consideration.

PS do you still want me to check yr anodes?
Click to expand...

Hi John
I assumed the fridge/freezer was 12volt on the basis that when I unplug the shore power i.e. remove 240v from the boat, the fridge continues to run without any involvement from me. I would have thought that I would have had to flick a switch enabling the fridge to run on 12 volt, if it wasn't 12 volt. Having said that I know nothing so I'm more than happy to be told I'm being a sirry iriot.:)
The batteries are all sealed so I assume they wont be running dry.


Re the Anodes - definitely yes. Any time to suit you. (I'm off work this week if this helps you) Did you get eh PM with my tel number?
 
Pretty sure some fridges "sense" the mains, if they are dual 12v/240v. (Just checked and Coolmatic ones do this, if plugged into the main they automatically run from the mains, if you unplug it, it runs from the 12v).

Mine doesn't though, it's 12v only. So if i want to leave the fridge on, the shore power has to be one. Easy enough to switch the charger of though.

That said, i leave the mains power on at all times, but the only thing that's left on is the charger. It's a decent multi-stage charger and the batteries appear to last well.
 
Last edited:
Thepipdoc said:
Hi John
I assumed the fridge/freezer was 12volt on the basis that when I unplug the shore power i.e. remove 240v from the boat, the fridge continues to run without any involvement from me. I would have thought that I would have had to flick a switch enabling the fridge to run on 12 volt, if it wasn't 12 volt. Having said that I know nothing so I'm more than happy to be told I'm being a sirry iriot.:)
The batteries are all sealed so I assume they wont be running dry.


Re the Anodes - definitely yes. Any time to suit you. (I'm off work this week if this helps you) Did you get eh PM with my tel number?
Click to expand...

No, no PM received. Yes most fridges will sense (or rather an inverter type device) will sense which voltage is available. If you're on shore power and turn your 12v supply off completely check then if your fridge is still running. I expect it will continue to run.
 
Last edited:
PaulGooch said:
Pretty sure some fridges "sense" the mains, if they are dual 12v/240v. (Just checked and Coolmatic ones do this, if plugged into the main they automatically run from the mains, if you unplug it, it runs from the 12v).

Mine doesn't though, it's 12v only. So if i want to leave the fridge on, the shore power has to be one. Easy enough to switch the charger of though.

That said, i leave the mains power on at all times, but the only thing that's left on is the charger. It's a decent multi-stage charger and the batteries appear to last well.
Click to expand...

Hi paul
Where is the battery charger switch on the 805?
I switch off the 3 switches under the steps which i assume operate the batteries (what else do they do).
Is there any useful info i can download on the 805 as i dont find the manual that informative.
 
gordhouse said:
Hi paul
Where is the battery charger switch on the 805?
I switch off the 3 switches under the steps which i assume operate the batteries (what else do they do).
Is there any useful info i can download on the 805 as i dont find the manual that informative.
Click to expand...

Just inside the patio doors, on the left. Three switches for shore power, battery charger and hot water heater.

The ones beneath the steps are isolators for the domestic and engine batteries, and the black one in the middle is 12v negative, we never turn that one off. Also under the steps is the overload reset for the anchor windlass.

Don't know of anywhere on the net for a useful manual.
 
You must log in or register to reply here.

Share this page

Top