A few Electrical/Battery questions?

[Matt341]

HI All,

Im hoping to have some help on a few questions. We bought the Konsort a couple of months ago and a lot of things are different on it to our previous boat. I have gone through the boat and everything seems brilliant. However, we have stayed onboard a few times and the immediate thing we notice is battery power, she has no charger and with a lot of lights on the levels are dropping fast. So I have the following questions -

1) At the moment there are 2x120ah sealed batteries (not leisure), connected to a battery selector switch. We were told to turn on the main isolator and then turn switch to "both", when staying onboard this means that both batteries are equally drained. There is housing for upto 3 batteries so im wondering whether to replace battery 2 with an 85ah leisure battery, I have 2 brand new 85ah leisure batteries in the garage so wondering whether to connect these together and then connect as Battery 2 in replacement of the second 120ah which is not a leisure. This means switch 1 would operate the 120ah non leisure and switch 2 would operate the 2 leisure batteries which are joined together. Therefore switch 1 as starter and switch 2 as domestic. Thoughts on this please?

2) There is a 30watt solar panel fitted permanently on the coachroof and a regulator fitted inside the cabin, in the battery area the solar panel is connected to battery 1 using crocodile clips, this means battery 2 isnt getting charged. I feel this is a waste as when I arrive at the boat the regulator is always flashing indicating that the battery is full, yet when i switch to both the voltmeter drops from just under 14 to 12 something, im guessing its because battery 2 isnt as full as battery 1. If I was to change the batteries in the order of Point 1 then how would I go about charging the batteries using the solar panel both at the same time. Should I run another wire from the regulator to battery 2 or split the current wire going to battery 1.

3) I am currently using an automatic battery charger from halfords which I am putting on the batteries individually until they are full, however, by the spring I would like to fit something permanent which could charge all the batteries at once automatically. There seem to be quite a few around, what would you suggest as the most reliable and the best suited for the battery sizes?

I hope this all makes sense.

I look forward to reading your suggestions.

Many Thanks
Ian

 

[andythilo]

HI All,

Im hoping to have some help on a few questions. We bought the Konsort a couple of months ago and a lot of things are different on it to our previous boat. I have gone through the boat and everything seems brilliant. However, we have stayed onboard a few times and the immediate thing we notice is battery power, she has no charger and with a lot of lights on the levels are dropping fast. So I have the following questions -

1) At the moment there are 2x120ah sealed batteries (not leisure), connected to a battery selector switch. We were told to turn on the main isolator and then turn switch to "both", when staying onboard this means that both batteries are equally drained. There is housing for upto 3 batteries so im wondering whether to replace battery 2 with an 85ah leisure battery, I have 2 brand new 85ah leisure batteries in the garage so wondering whether to connect these together and then connect as Battery 2 in replacement of the second 120ah which is not a leisure. This means switch 1 would operate the 120ah non leisure and switch 2 would operate the 2 leisure batteries which are joined together. Therefore switch 1 as starter and switch 2 as domestic. Thoughts on this please?

2) There is a 30watt solar panel fitted permanently on the coachroof and a regulator fitted inside the cabin, in the battery area the solar panel is connected to battery 1 using crocodile clips, this means battery 2 isnt getting charged. I feel this is a waste as when I arrive at the boat the regulator is always flashing indicating that the battery is full, yet when i switch to both the voltmeter drops from just under 14 to 12 something, im guessing its because battery 2 isnt as full as battery 1. If I was to change the batteries in the order of Point 1 then how would I go about charging the batteries using the solar panel both at the same time. Should I run another wire from the regulator to battery 2 or split the current wire going to battery 1.

3) I am currently using an automatic battery charger from halfords which I am putting on the batteries individually until they are full, however, by the spring I would like to fit something permanent which could charge all the batteries at once automatically. There seem to be quite a few around, what would you suggest as the most reliable and the best suited for the battery sizes?

I hope this all makes sense.

I look forward to reading your suggestions.

Many Thanks
Ian

1) You'd be better having the 2 120Ah batteries as house, and the 85 as engine.

2) I wouldnt bother using the solar power to charge the engine battery. Unless you're doing a lot of flooded starting it will hold it's charge well. I dont know your boat but your engine should have a charging capability?

3) A decent multi output charger like one of the Sterling range will suffice.

You may want to consider a small suitcase genny to provide mains and charging capability when at anchor. A 1000W genny will do you well. A 20A 12v charger will pull no more than 300W.

 

[Matt341]

Thanks for your comments,

My concern with the 120ah batteries are that they are non leisure, e.g. car batteries so im wondering whether they are likely to be any good for using water pump, lighting etc.

Once the engine has run for a while both batteries are fully charged and the regulator is off so im guessing the alternator is capable of the capacity.

Thanks for the suggestion on chargers, I was thinking of sterling as they seem the most popular around.

I am keen to split the batteries, especially if on anchor it would be a bad situation to have both flat and unable to start the engine. My only concerns are that there are 2 thick neg/pos wires going to each battery but I think battery 1 has a few other wires coming off the terminals, im wondering if they are some of the instruments though, if so it wouldnt be a problem as these are only used when we are sailing.

Thanks again
Ian

 

[VicS]

I agree with Andythilo.

connect the two 120 Ah batteries together as a domestic bank and connect them to terminal 2 of the isolator. Fit the 85 Ah battery and connect it to terminal 1.

Use the 85 Ah battery for engine starting and the 2x120Ah bank for domestic services.

Select 1 start the engine when it has been running long enough to recharge that battery switch to position 2. BUT when the engine is running always switch via the BOTH position.

Connect the solar panel via a suitable fuse to the 2x120ah battery bank

Use your charger as you do at present to charge which ever battery bank needs charging but invest in due course in a dual output charger so that both banks can charged simultaneously when necessary.

Also in due course consider a more sophisticated charging system from the engine alternator. Something that automatically recharges both battery banks. Maybe just a simple VSR based system or maybe some bit of electronic wizardry from Mr Sterling.

 

[andythilo]

Thanks for your comments,

My concern with the 120ah batteries are that they are non leisure, e.g. car batteries so im wondering whether they are likely to be any good for using water pump, lighting etc.

Once the engine has run for a while both batteries are fully charged and the regulator is off so im guessing the alternator is capable of the capacity.

Thanks for the suggestion on chargers, I was thinking of sterling as they seem the most popular around.

I am keen to split the batteries, especially if on anchor it would be a bad situation to have both flat and unable to start the engine. My only concerns are that there are 2 thick neg/pos wires going to each battery but I think battery 1 has a few other wires coming off the terminals, im wondering if they are some of the instruments though, if so it wouldnt be a problem as these are only used when we are sailing.

Thanks again
Ian

I wouldnt worry about the batteries, unless their old and past their best. They'll be fine for house batteries, all batteries are the same pretty much anyway, it's only the thickness of the plates that varies on real deep cycle batteries I believe.

To do it properly in my opinion, install a VSR cluster. One like this :

http://www.power-store.com/view-item.asp?itemid=1156

Basically what it does it provide all your battery isolation and split charging in one box and also provides an emergency parallel in case the engine battery dies.

It includes a VSR (voltage senstive relay) that when charging, charges the engine battery first and then once that has reached a set voltage (13.8v I think) it allows the house battery to charge.

The emergency parallel connects both engine and start batteries together so that you can use the house batteries to start the engine.

Both charger and solar charger inputs would be across the engine battery, allowing the VSR to regulate the charging.

It's probably best to trace your system as it is and do a schematic so that you know where everything goes.

It would also be beneficial to fit a battery monitor, either the NASA battery monitor, or the Victron BMV-600.

Hope this helps.

 

[VicS]

but I think battery 1 has a few other wires coming off the terminals,

Identify any wires connected directly to the batteries. Move any that do not need a permanent supply to the common terminal of the isolator and fuse them.

Supply anything that needs a permanent supply from the domestic bank and make sure the connection is fused.

Don't have anything supplied directly from the starter battery you need to be sure that when it is not selected by the isolator nothing is trying to run it flat!

 

[halcyon]

I wouldnt worry about the batteries, unless their old and past their best. They'll be fine for house batteries, all batteries are the same pretty much anyway, it's only the thickness of the plates that varies on real deep cycle batteries I believe.

To do it properly in my opinion, install a VSR cluster. One like this :
.

Westerlys were fitted with Delco Freedom batteries, and owners have replaced them with the same, they are totally different. I used to supply battery chargers to them that charged upto 15.4 volt and floated at 14.6 volt, to suit these batteries. So check what you have, as it may effect your plans to keep them.

Most Westerly's after around 1984 were fitted with P4000 VSR systems, and is still in production, though very up-dated. Some boats ( Merlin's ) were fitted with one battery bank, and the VSR output linked. Producing odd displays on battery status display, these are convertable to two battery banks at little cost.

Brian

 

[philip_stevens]

PM sent.

 

[Matt341]

Thank you everyone for your suggestions.

I am now 99% sure that the leads coming off the 1 battery are for various memory. FM radio, possibly chartplotter etc.

All batteries were new last year, there is an 85ah which is not connected to the system and only used for an alarm light which I thought was a waste so have brought it home to put on a smart charger, the light was quite annoying when staying on board, SWMBO said at 3 in the morning that she thought the police were flashing a light in our cockpit lol

My only other major concern now is charging, as the FM radio memory etc. are coming off the number 1 battery I feel that both batteries should have the solar panel connected. One thought says to leave the solar panel connected to engine start but then house battery is going to get flat until we run the engine. I was thinking of splitting the wires from the solar regulator just before the current croc clips, however this would cause the batteries to be put into parallel.

I really would be grateful for help on this, how can I connect the solar panel to both batteries without connecting them in parallel?

Many Thanks
Ian.

 

[halcyon]

I really would be grateful for help on this, how can I connect the solar panel to both batteries without connecting them in parallel?

Just feed the solar panel through a diode splitter, 1 in, 2 out. depending on loading you may get away with just diodes, or you may need a heatsink.

Brian

 

[Tranona]

As already suggested fit a BEP Marine switch cluster and VSR from Merlin. The 85 amp as engine and the 2*120 in parallel as house batteries - which is actually a lot of capacity for the size of boat, particularly if you are not running power hungry things like a fridge. You can also wire in an "always on" circuit from one of the house batteries for such things as memories and automatic bilge pumps. Merlin will design you a wiring circuit to meet your needs and supply all the ancilliary components if you want to go down that route.

For charging, I suspect your standard alternator will struggle to charge the house batteries if you use them a lot, so you will need to consider either a larger alternator or a boost system such as Sterling. For mains charging don't mess around with car chargers. Get a proper automatic multistage charger with outputs for more than one battery which can be set for the type of batteries you have. Something like a Synergex 25 amp would be adequate at the budget end, but there is plenty of choice. The Solar panel is more than adequate to keep the house batteries topped up when not being used. I use a 7 watt on a 170 AH bank. No need to charge the start battery as the switch cluster has an emergency parallel switch.

Hope this helps

 

[rivonia]

Forget everything that everyone has told you DUMP the car batteries and get two deep cycle batteries. Car batteries are designed for cranking and fast charge. Deep cycle are built and designed to SLOWLY discharge and to be SLOWLY charged. So a solar panel would be ideal as would a wind turbine. Fit a sterling charger batt, management systen,

Peter

 

[William_H]

Solar charging

If you want to charge all batteries from the solar panel but keep the batteries isolated you need to do away with the solar regulator and charge the batteries direct from the panel. The panel should have an isolation diode fitted and to charge different banks while remaining isolated you need additional diodes. Preferably fitted from the panel itself so use the original diode to one bank and an additional similar to the other banks.
Or if that is difficult just add another pair of isolating diodes from +ve of the panel to each battery bank pos.
Fit the diodes either near the battery terminal or fit fuses.

You can not fit isolation diodes after the regulator because the regulated voltage will already be reduced to 14v and any diode then in series will reduce this too far. Better to start with the max 20v of the panel so any reduction by diodes is of little consequence. With the size of battery you have 30w can never do any harm to the battery banks even under max output but it does mean that all the solar power goes into the batteries all the time.

yes I think you should go to a VSR system and get rid of the 1,2,both switch. Then use the 85AH for engine and the 2 bigger batteries in paralell for domestic. good luck olewill