Hot Battery..!

[Vaughan]

This is just an assumption as I don't know your boat, but you say that the yellow light means that something is being used?

The starter battery is getting a trickle charge only, as it is fully charged.  The charge on the other battery may be the aggregate difference between the power coming in from that solar panel, and the power being used by the fridge.  A 12v fridge uses about 5 amps when running and this is about the same as the power of an average solar panel.

I am interested that only one domestic battery is accepting a charge, but the other one is not.  Maybe that is the one that you didn't replace?

[Vaughan]

On 04/10/2020 at 18:24, FreedomBoatingHols said:

Battery is being overcharged or is knackered; potentially both now. Hot wires is a sign of too much current

I "liked" this post when I read it but it was later that we saw the picture of your battery monitor.

14.8 volts is a high charge and could cause overheating in the wiring.

Maybe your alternator needs an inspection as well?

[annv]

Hi Jemka I would suggest that as you don't know your electrical system that you get someone to do you a wiring diagram while the system is working, if you wait until it goes wrong it will be more difficult to fix if no diagram and not a conventual layout,  plus it may be not connected/wired up the best way for you or safest way,   hire boats get quick fixes to get them going when on hire, it may be not safe as it is,   certainly three starter batteries are not needed to start most boat engines, it is better to keep the starter battery separate from the rest of system,have you had the boat long and have you commissioned a bss or did it come with it when you bought it. John

[StillCruising]

The solar panel is generating 14.8 volts at 0.6 amps, the MPPT controller is converting it to 13.5 volts at 0.6amps. I have a 100watt panel and have seen up to 20 volts being generated but the controller manages it and converts to the voltage and amperage required.

[Meantime]

14 minutes ago, StillCruising said:

The solar panel is generating 14.8 volts at 0.6 amps, the MPPT controller is converting it to 13.5 volts at 0.6amps. I have a 100watt panel and have seen up to 20 volts being generated but the controller manages it and converts to the voltage and amperage required.

Was just about to say the same. The display is the remote panel for the MPPT controller. The left hand symbol is the solar panel. The middle symbol is the battery bank receiving 0.6A from the solar panel. The right hand symbol would be the alternate charge, in case case from an alternator which is showing 0A as the engine is stopped. 13.5v is about right for a fully charged battery that is still receiving a trickle charge from the solar panel. 

The issue occurred after the engine had been running, so it would be interesting to take a note of the charge being supplied by the alternator, the right hand symbol when the engine is running. If it also settles to around 13.4 or 13.5V then it was probably just a faulty battery.

Would be concerned about not being able to isolate the fridge though, that is a BSS failure. How do you turn it off when you go home?

[Regulo]

This make anything clearer?

[Vaughan]

Well, Glory Halleluhia!

There's nothing like making things as electronically complicated as possible, is there?

If you want to trust some gadget like that, I hope you do well with it.

[Guest]

1 hour ago, Meantime said:

Would be concerned about not being able to isolate the fridge though, that is a BSS failure. How do you turn it off when you go home?

There is an isolator switch for the fridge, and it passed BSS last week with a minor issue regarding the diesel heater which was rectified.

[Meantime]

1 minute ago, Jemaki said:

There is an isolator switch for the fridge, and it passed BSS last week with a minor issue regarding the diesel heater which was rectified.

I was just going by your previous post,

  

20 hours ago, Jemaki said:

When all batteries are isolated the bloody fridge still works...to the delight of the wife!.

Which would be a BSS failure!

[StillCruising]

There seems to be some confusion as to what the RH Load icon is showing. The load is just an output from the control panel which you can use under conditions that you can set. It is sometimes used to power a light on a timer for instants. Personally I don't use this facility. 

[Guest]

These photos give a better idea of setup, and touch wood since changing the rogue battery all is now back to normal, the other 2 were checked and found to be OK and we replaced the 2 leisure batteries last week. I have to hold my hands up as the fridge does switch off when the batteries are isolated . The higher figures on the panels are with engine running and the relay which is part of the 3 battery setup reduces domestic power should the batteries fade to ensure enough umph to start the engine. Power loss crept up on us over a 3 week period eventually dwindling so that after an hour we had to switch to shore power, as stated earlier with sufficient engine use we are back to normal. Thanks all for putting in your "two pennarth" it makes interesting reading even if I don't understand it all 

Ps.....as stated by posters it does appear that one of the 3 batteries is wired stand alone for starting the engine and the other 2 go towards leisure. 

[Vaughan]

1 hour ago, Jemaki said:

it makes interesting reading even if I don't understand it all 

I cannot imagine how I have managed to run several hundred hire boats in my time without need of these little electronic "Black Boxes" *

 

1 hour ago, Jemaki said:

This photo shows very clearly that your 3 "domestic" batteries are not wired together.  Look at the red positive cables.

In addition these are batteries of a lead/acid type where the electrolyte can be topped up by screw plugs.  But they are not installed in a sealed box, vented overside from high level, in accordance with ERCD and (I assume) B.S.S., to prevent hydrogen explosion in the event of an overcharge by a failed alternator regulator.  Funny your recent inspection didn't pick this up?

I don't mind in the least being superannuated by little LCD screens but I would like to say to members reading this that what I have said earlier on this thread is factually accurate.

To Jemaki I would suggest that you might like to have your system looked over by a reputable boatyard.

 

 

* Black Box is a term used by RAF pilots to describe little bits of solid state electronic kit in an aircraft whose purpose is not obvious; which cannot be adjusted in any way; which may fail at any time and which cannot be mended in flight. The only breakdown solution is to throw it away and buy a new one.

 

[Guest]

12 minutes ago, Vaughan said:

This photo shows very clearly that your 3 "domestic" batteries are not wired together.  Look at the red positive cables

Thanks for the feedback Vaughan (I did mention about the battery being stand alone at the end of my post 🍻)

[Smoggy]

34 minutes ago, Vaughan said:

Black Box is a term used by RAF pilots to describe little bits of solid state electronic kit in an aircraft whose purpose is not obvious; which cannot be adjusted in any way; which may fail at any time and which cannot be mended in flight. The only breakdown solution is to throw it away and buy a new one.

Not to mention the irony that the main lump known as a "black box" in aircraft is normally orange.....

I don't think high level external venting is part of the bss for batteries just secure and terminals covered, not sure of age of boat so can't say anything about ercd regs, it is for gas/fuel for sure but the flammable part of a fizzing battery is lighter than air so doesn't collect in bilges like gas/fuel fumes.

[Vaughan]

11 minutes ago, Smoggy said:

it is for gas/fuel for sure but the flammable part of a fizzing battery is lighter than air so doesn't collect in bilges like gas/fuel fumes.

Hence the need for high level ventilation as per ERCD.

[Oddfellow]

8 hours ago, Vaughan said:

I "liked" this post when I read it but it was later that we saw the picture of your battery monitor.

14.8 volts is a high charge and could cause overheating in the wiring.

Maybe your alternator needs an inspection as well?

Maybe the Solar Controller is set for the wrong type of battery......

 

[Islander]

Having just read this I think you will find the 14.8v reference is the solar panel voltage and not the charge voltage. The solar charge controller is a fairly common type for small off grid/RV setups but now being used on boats but without using the load connections. A better indication to battery charging/usage would be a Victron or NASA battery monitor. The solar charge controller is not going to show what your alternator is doing.
Out of interest, does the inverter run the fridge. As Vaughan has said, it would be a good idea to get a marine electrician to give it a once over and draw up a basic circuit diagram for you ( I really must do mine ).

Colin 

[Guest]

10 hours ago, Islander said:

Out of interest, does the inverter run the fridge.

The simple answer is no.

[Vaughan]

16 hours ago, Jemaki said:

 

I would ask you to please understand that I don't wish to criticise for the sake of it, but you have shown photos and I feel responsible to point out some matters of safety.

I have looked up the BSS this morning, as I am more used to ERCD (which is more stringent), but I have found the following :

 

Relevant BSS general requirements.

9/. All electrical systems must be capable of being safely and quickly disconnected from their power source(s) in an emergency.

11/. All battery compartments containing unsealed or open vented batteries must be adequately ventilated to prevent a build-up of a flammable mix of gases.

Battery storage.

3.1.1.  All unsealed batteries must be stored within a ventilated space.

          Dedicated battery boxes . . . must be ventilated at the top  or the highest point of the sides . . . and any ductwork        used must run horizontally or upwards. The ventilation pathway . . . .  must lead to the outside of the hull or superstructure.

3.6.1.  Battery isolators must be fitted to each bank of batteries.

3.6.2.  All DC electrical circuits must pass through a battery isolator. (there are exceptions, but the fridge is not one of them).

I am familiar with the type of batteries on your starter and domestic bank, and they are very good ones, which will accept a deep cycle and have a long life.  But if they are charged too fast or at too high a voltage they will "gas off" and need their electrolyte levels checked regularly.  In fact, lack of electrolyte may have been the cause of your battery failure.

ERCD says that the battery box must be watertight to contain spilled acid and must be corrosion resistant material such as GRP, but not metal.

Looking at your photo, that battery box for your inverter batteries is fine, so long it has a lid and is ventilated outside. Pity someone has drilled a line of holes in it though!  Also funny, that those two batteries are sealed type, so they don't need a box.

I guess that the thick red cable is feeding the inverter, as anything of 1000 watts or more must have "starter" size cable.  I think another red wire would be the charge feed, coming in from the alternator through a charge splitter.  So what is that other red wire?  That wouldn't be your fridge, would it?  If so, it would have to have a fuse, readily visible and accessible.  But even then it would fail as it is not an appliance that is allowed to bypass the master switch.

Your inverter may bypass a master switch but in that case it must have a suitable fuse in the circuit which is visible and readily accessible.  In which case, it seems your 2 batteries do not have a master switch.  Unless you count the fridge circuit, in which case it must have one.

If you have just had an inspection and passed, then it is up to you, of course.  My recommendation would be to wire the inverter through an accessible master switch and then wire the fridge to the switch.  That would cover all the angles!

 

[Meantime]

Looking at the picture of the Durite relay more closely, I'm not convinced it is even doing anything. The wires connected to the contacts appear to have been cut off. If so the wires going to the coil of the relay are redundant. I would investigate if they are live and consider if they are redundant, stripping them out.

[Meantime]

It's also worth pointing out that even sealed batteries should be vented. They normally contain a vent system in the top of the case to allow excess gas to escape if the battery is overcharged. Normally it requires a pressure of 2-3 psi to open and will then release gas.

The BSS does contain a note that makes reference to this.

NOTE ‐ if batteries of a ‘sealed’ type are stored in a non‐ventilated space verify that storage in
unventilated spaces meets with the battery manufacturer’s recommendations by reference to presented
documentation from the manufacturer.

Most modern charging systems support fast charging to top batteries up as quickly and fully as possible. Advanced regulators are a good example of this. However it is not possible to fast charge without loosing water or some gas. For this reason a lot of people still suggest that unsealed batteries are better because fast charging will cause loss of water and you can at least top it up then. Water loss from sealed or maintenance free batteries cannot be replaced.

[Vaughan]

15 minutes ago, Meantime said:

I would investigate if they are live and consider if they are redundant, stripping them out.

I was also wondering what that loose red wire is, in the bottom of the photo in my post. I hope it's not connected to anything? 

[Meantime]

10 minutes ago, Vaughan said:

I was also wondering what that loose red wire is, in the bottom of the photo in my post. I hope it's not connected to anything? 

Good spot, that looks very much like it is taped back on itself and not connected to anything at that end, but where is the other end?

[annv]

I might also add that the cables are not greased with silicone/vasalend and a more efficient way of connecting batteries s this. John

[Islander]

1 hour ago, Meantime said:

Looking at the picture of the Durite relay more closely, I'm not convinced it is even doing anything. The wires connected to the contacts appear to have been cut off. If so the wires going to the coil of the relay are redundant. I would investigate if they are live and consider if they are redundant, stripping them out.

Looks like the Durite relay has been replaced by the digital charge relay. The heavy gauge wires just chopped and transferred. The thin wires now redundant and probably from alternator warning light.

The boat was no doubt built with the most basic of electrics and has over the years had numerous add ons without the removal of redundant circuitry. 
 

Colin