shore power quandary

[arthor]

Greetings all.

I have just been down to the boat full of enthusiasm with Spring approaching to find my starter battery dead. House bank is fine.

I'd finally got my shorepower sorted before chistmas and set the rotary switch to shore. Thought that would all my batts in order over the winter.

I have a Mastervolt combi thing which seems to allow one bank only to be selected at a time. It had domestic selected. Not sure if this matters for this problem but I have now selected starter. Is there any chance that there may now be charge going to my starter battery?

I can go back down and take pictures of the set up, if that is useful.

Anyone know of a suitable electrian near Leeds?

Any help, much appreciated

[Tony Brooks]

2 minutes ago, arthor said:

Greetings all.

I have just been down to the boat full of enthusiasm with Spring approaching to find my starter battery dead. House bank is fine.

I'd finally got my shorepower sorted before chistmas and set the rotary switch to shore. Thought that would all my batts in order over the winter.

I have a Mastervolt combi thing which seems to allow one bank only to be selected at a time. It had domestic selected. Not sure if this matters for this problem but I have now selected starter. Is there any chance that there may now be charge going to my starter battery?

I can go back down and take pictures of the set up, if that is useful.

Anyone know of a suitable electrian near Leeds?

Any help, much appreciated

 

Depends upon how the charger is wired into the system but in many cases setting it to both will do what you want but then the whole boar electrics would be left turned on. I think that I would pop a jumps lead between the engine and domestic bank positives and leave the switch as it was set over winter.

 

If you have and can use a voltmeter then you could check the voltage on both banks with the charger on and the switch in the various positions.

[Guest]

5 minutes ago, arthor said:

Greetings all.

I have just been down to the boat full of enthusiasm with Spring approaching to find my starter battery dead. House bank is fine.

I'd finally got my shorepower sorted before chistmas and set the rotary switch to shore. Thought that would all my batts in order over the winter.

I have a Mastervolt combi thing which seems to allow one bank only to be selected at a time. It had domestic selected. Not sure if this matters for this problem but I have now selected starter. Is there any chance that there may now be charge going to my starter battery?

I can go back down and take pictures of the set up, if that is useful.

Anyone know of a suitable electrian near Leeds?

Any help, much appreciated

 

You may be able to revive it but if its been flat a long time its likely to be goosed.

[Alan de Enfield]

Battery chargers are commonly only wired thru to one-bank. Some chargers will have multiple take off terminals giving a supply to more than one bank.

 

It is the 'norm' to leave the boat with a 'jump-lead' bridged across the two battery banks postive (+) terminals so it can charge both together.

 

I do this with my solar panel over Winter. 

[David Mack]

Or a voltage sensitive relay (VSR) will do the same automatically.

[arthor]

19 minutes ago, Alan de Enfield said:

Battery chargers are commonly only wired thru to one-bank. Some chargers will have multiple take off terminals giving a supply to more than one bank.

 

It is the 'norm' to leave the boat with a 'jump-lead' bridged across the two battery banks postive (+) terminals so it can charge both together.

 

I do this with my solar panel over Winter. 

Interesting. Surprised there isn't some sort of facility for this to be enabled in the system.

 

thank you all for your help.

I will see what it looks like in a few days. 

The jumper idea. Is that just one lead? pos to pos?

[Tony Brooks]

47 minutes ago, arthor said:

Interesting. Surprised there isn't some sort of facility for this to be enabled in the system.

 

thank you all for your help.

I will see what it looks like in a few days. 

The jumper idea. Is that just one lead? pos to pos?

 

Yes

[nicknorman]

1 hour ago, arthor said:

Greetings all.

I have just been down to the boat full of enthusiasm with Spring approaching to find my starter battery dead. House bank is fine.

I'd finally got my shorepower sorted before chistmas and set the rotary switch to shore. Thought that would all my batts in order over the winter.

I have a Mastervolt combi thing which seems to allow one bank only to be selected at a time. It had domestic selected. Not sure if this matters for this problem but I have now selected starter. Is there any chance that there may now be charge going to my starter battery?

I can go back down and take pictures of the set up, if that is useful.

Anyone know of a suitable electrian near Leeds?

Any help, much appreciated

You don’t mention which model of Mastervolt you have. Our Mastervolt Mass Combi 12/2500/100 has a secondary small connection to keep the starter battery charged, maximum 6A which is more than enough.

 

But as a general point, a starter battery should not go flat when left unattended over winter unless either it is knackered, or if there is some load connected to it eg a bilge pump.

[arthor]

we had the eberspacher changed out to a Webasto in October. Might get them out to test the batt, replace if necessary and give me a quick run down of what I need to set all the switches to for various scenarios. It would be worth a few hours labour charge to get it right.

I may have a pic of our Mastervolt thing.

[Guest]

50 minutes ago, nicknorman said:

You don’t mention which model of Mastervolt you have. Our Mastervolt Mass Combi 12/2500/100 has a secondary small connection to keep the starter battery charged, maximum 6A which is more than enough.

 

But as a general point, a starter battery should not go flat when left unattended over winter unless either it is knackered, or if there is some load connected to it eg a bilge pump.

 

Ours was wired the same.

[arthor]

Been down to the boat and taken a pic of my Mastervolt thing.

Starter batt still reading zilch. One thing I did notice was that my house batts were reading 11.9v. I switched my inverter from 'off' to 'charger only' and they immediately went up to 13 plus. Can I take it that indicated there was now charge going to the house batts? This didn't happen with the starter batt. 

I'm thinking that I may have figured out how to charge both banks, albeit seperately but the starter batt is now beyond help.

[Tony Brooks]

Yes. the house batteries are probably charging and the voltage should gradually rise over the next several hours. Once they are getting on for 14 volts put a jump lead between the engine and domestic battery positives and see what happens. It should then charge the engine battery unless it is totally ruined.

 

Note 14V is nowhere near fully charged you need no more than 1 to 2% of the battery capacity in amps going into the domestic bank before you can consider them fully charged, so 3 x 110 Ah batteries you would be looking for no more than 6 or 7 amps charge.

 

Amps and volts is what you need, the other scales are likely to help you damage the batteries.

Edited February 23, 2022 by Tony Brooks

[frangar]

Note that the "Batt 1" and "Batt 2" switch just selects which bank the voltage is being read from...and for Batt 1 the current (amps). It wont select where the charge is going from the combi or charger....that will only be changed if you have a VSR or 1/2/Both changeover switch. You would hope its wired for Batt 1 to be domestic and Batt 2 to be starter but with boats its best never to assume. 

[Alan de Enfield]

12 minutes ago, frangar said:

You would hope its wired for Batt 1 to be domestic and Batt 2 to be starter but with boats its best never to assume. 

 

Correct - never assume.

 

For me the most important battery is the engine starter, if you can start the engine you can move the boat, charge the other battery bank and get hot water. Therefore "Batt1" is the starter (most important) battery.

 

The domestic bank is just for 'comfort' (running water, lights, TV etc) and in the greater scheme of things is far less important - hence the 'domestic batteries are "Batt2"

 

Seems logical to me.

 

 

 

Edited February 23, 2022 by Alan de Enfield

[frangar]

13 minutes ago, Alan de Enfield said:

 

Correct - never assume.

 

For me the most important battery is the engine starter, if you can start the engine you can move the boat, charge the other battery bank and get hot water. Therefore "Batt1" is the starter (most important) battery.

 

The domestic bank is just for 'comfort' (running water, lights, TV etc) and in the greater scheme of things is far less important - hence the 'domestic batteries are "Batt2"

 

Seems logical to me.

 

 

 

I’d need to check the specs of that now old micc panel but as I recall only one bank could read amps via a shunt….the other was voltage only…and I thought it was bank 1 that did both….however it’s been many years since I fitted one so I might be mistaken…However it definitely doesn’t select where the charge is going! 

 

~Edited to add

 

Ive had quick google and cant find a manual for the 2 bank version to check which bank does what....the Mastervolt website only shows the later version.

Edited February 23, 2022 by frangar

[arthor]

Many thanks again.

Think I will give it a few days and go down to try the jump lead thing if I know for sure the house batts are getting a charge. I'm assuming that would only be for when the boat is "stood" and on shore power.

There are a couple of stickers next the Mastervolt that say house is 1 and starter is 2. The voltage suggests that is correct.

Now that I know I have shorepower and mains outlets, I have had an idea. When I park my bike up in the garage for any length of time, I plug in a Tecmate battery optimiser. Just wondered if one of those plugged in would keep the starter batt topped up. Just a thought.

[frangar]

2 minutes ago, arthor said:

Many thanks again.

Think I will give it a few days and go down to try the jump lead thing if I know for sure the house batts are getting a charge. I'm assuming that would only be for when the boat is "stood" and on shore power.

There are a couple of stickers next the Mastervolt that say house is 1 and starter is 2. The voltage suggests that is correct.

Now that I know I have shorepower and mains outlets, I have had an idea. When I park my bike up in the garage for any length of time, I plug in a Tecmate battery optimiser. Just wondered if one of those plugged in would keep the starter batt topped up. Just a thought.

A Tecmate or Ctec unit would work but if as I suspect the Combi is a mastervolt Dakar then there should be as others have mentioned an outlet on the board to trickle charge a starter battery.....although I have come across the odd unit which didnt have one for some reason....you need to take the front cover off the dakar...and make sure its disconnected from the 240v etc....even then there is the chance of the capacitors still holding a charge so be wary what you poke about in....you should find a small "chocblock" type terminal marked trickle charge or similar....the Dakar manuals are on the Mastervolt website if you dont have one. Note you only need a positive wire from the Dakar to the battery via a suitable fuse....the negative is done via the common negative to the combi.

[Slim]

arthor, you don't seem to have been specific about which Mastervolt combi you have.. I have a Mastervolt Mass 12/2000/80. The exact outputs aren't too important as several models  used the same design. I also have a Mass MICC which displays in a slightly different way to yours but seems very similar.

My MICC display gives full monitoring info on the domestic Bank but not on the start battery. It does however show the start battery Voltage if selected.

On my combi the main charger output goes to domestic Bank. There is also a supplementary, dedicated terminal (6 amp output). This terminal is underneath the removal panel at the bottom of the combi. This output should be fused at installation, it's not in the unit itself. So, if the wiring exists it could be the fuse.

I'm on the boat for a few days so if I can provide info please ask

Full installation instructions should be on the Mastervolt site but to be honest I find navigating it a nightmare.

[MtB]

8 hours ago, Alan de Enfield said:

For me the most important battery is the engine starter,

 

For me it is the opposite. The domestic bank needs looking after first as it is by far the more expensive to replace if goosed by under charging.

 

After all you can still start the engine if the starter battery dies using a single jump lead, as you yourself explained earlier in this thread  

[arthor]

I'll check what Mastervolt it is.

The boat is over 20 yrs old, so I suspect the electrics may have been put in over time.

When cruising, I'm happy everything gets charged, so I'm not sure I want to mess too much.

As it only seems to be an issue when she's parked up over the winter on shore power,, as long as I can get them all charging via a jump lead, I can live with that. If the starter doesn't charge, I'll take it on the chin and swap it out and hopefully be forewarned for next winter.

The 5 house batts are brand new, so the point made about looking after them due to expense is very valid indeed.