battery replacement tips

[nipper]

I might be being thick here, but, if all the negatives are at one end of the battery bank (as they should be & mine now are) and all the positives are at the other end (ditto) if you removed a pair of links between two batteries would this not effectively kill the whole system?

 

Steve

 

 

Hi

I want to remove my batteries I have read your pinned thread but still confused too technical for me.

I have three domestics and engine start one isolation switch for domestic and one for engine.

Do I just turn off isolations switches and disconnect negs first then pos and reconnect in reverse

I have no battery monitor ect.

 

Seems to me that the OP asked a perfectly good question, and the subject has been overshadowed with technicalities!

All we really want to know is what bit of wire comes off first and what bit comes off last!

I for one got so confused that I am getting a boat yard to supply and fit my bank of four batteries, today, for the labour cost of £45.

I now can relax in the knowledge that if someone mucks up. it's down to them!

Nipper

[smileypete]

Hi

I want to remove my batteries I have read your pinned thread but still confused too technical for me.

I have three domestics and engine start one isolation switch for domestic and one for engine.

Do I just turn off isolations switches and disconnect negs first then pos and reconnect in reverse

I have no battery monitor ect.

 

OK I would do the following:

 

• Isolate or remove any connections that bypass the battery isolator(s).
  
• Open the battery isolator(s).
  
• Remove the negative connection from the bank
  
• Remove the links between the batteries
  
• Remove the positive connection from the bank
  
• Remove the batteries
  
• Place the new batteries in the same place and reverse the above procedure.
  

 

cheers,

Pete.

[luda]

HI

 

Thanks for that info Pete Just the sort of answers us numptys want no frills

[Gibbo]

OK I would do the following:

 

• Isolate or remove any connections that bypass the battery isolator(s).
  

 

 

So, whilst you have your spanner on the battery positive post (whilst eveything else is still connected) why not simply disconnect the battery positive?

 

 

Seems to me that the OP asked a perfectly good question, and the subject has been overshadowed with technicalities!

All we really want to know is what bit of wire comes off first and what bit comes off last!

 

Unfortunately that's often the result when someone expects a simple answer to a subject that isn't simple. A simple answer often implies the person who wrote it understands the subject no better than the person who asked the question.

 

It's just the way it is I'm afraid. Wanting a simple answer doesn't mean one is possible.

[smileypete]

So, whilst you have your spanner on the battery positive post (whilst eveything else is still connected) why not simply disconnect the battery positive?

 

Anything that bypasses the battery isolator should be fused near to the battery. So it's just a matter of pulling the fuse, or a connection to/from the fuse holder(s).

 

cheers,

Pete.

Edited November 7, 2010 by smileypete

[Gibbo]

Anything that bypasses the battery isolator should be fused near to the battery. So it's just a matter of pulling the fuse, or a connection to/from the fuse holder(s).

 

Aye I'll grant you that..... What about all the ones that aren't fused (because many boat electrical systems are a complete mess)?

 

I know, just disconnect the positive first. End of problem

[smileypete]

Aye I'll grant you that..... What about all the ones that aren't fused (because many boat electrical systems are a complete mess)?

 

I know, just disconnect the positive first. End of problem

I'd either fit a fuse or walk away.

 

cheers,

Pete.

[malbro]

What am I missing ?

Point taken about spanner and metal bat. box , get a flexible attachment for your short box spanner .

I do not see then , why if all power is off , you do not disconnect the positive , ( any and all ).

Edited December 30, 2010 by malbro

[jonkil]

My background is in vehicle wiring.

More accurately aircraft and bespoke automotive applications, with 30+ years in the industry, and in the past 10 years a dedicated CAN-bus design and applications field.

Wiring is relatively simple, MOST wiring will work in one form or another !.... even poorly designed systems.

I am a firm believer in KISS systems (keep it simple stupid), it is easier to sort out when it goes wrong.

Electric is identical to water, it flows, it leaks, it turns on and off. The idea of wires melting and units "blowing" is correct, but for this to happen the circuit must have energy (power), simple.... no energy, no problem.

The preliminary circuit shown below will alleviate any of the above problems, if the isolator is OFF then NO ENERGY will be in the system, no wires will burn, no units will "blow".... PROVIDED there is no other supply within the system (eg) 12v being back fed from a charging item e.t.c

The engine starting supply is completely separate, not integrated with this system at all. If charging of the leisure batteries is provided from engine alternator then a split charge relay is absolutely necessary to isolate the 12v supply from the engine starting battery when the engine is stopped.

I hope this helps.

 

John

Edited January 12, 2011 by jonkil

[WotEver]

I just noticed this post in this old thread. It's not perfect.

 

The first time someone turns off the isolator when the engine is running with the alternator under load the alternator will burn out.

 

When leaving the boat with a shore-power charger connected you'd have to leave all the rest of the boat electrics turned on.

 

When leaving the boat with the fridge turned on you'd have to leave all the rest of the boat electrics turned on.

 

If you have central heating you'd have to leave all the rest of the boat electrics turned on.

 

Tony

 

If you have a bilge pump, you'd have to leave all the rest of the boat electrics turned on.

[sebrof]

I just noticed this post in this old thread. It's not perfect.

 

The first time someone turns off the isolator when the engine is running with the alternator under load the alternator will burn out.

 

When leaving the boat with a shore-power charger connected you'd have to leave all the rest of the boat electrics turned on.

 

When leaving the boat with the fridge turned on you'd have to leave all the rest of the boat electrics turned on.

 

If you have central heating you'd have to leave all the rest of the boat electrics turned on.

 

Tony

 

If you have a bilge pump, you'd have to leave all the rest of the boat electrics turned on.

 

I don't know about your boat, but all my circuits have their own circuit breakers.

 

No problem to turn off whatever you want to turn off.

[WotEver]

I don't know about your boat, but all my circuits have their own circuit breakers.

 

No problem to turn off whatever you want to turn off.

Mine is old. It has fuses. No way of turning off any circuit without removing fuses. That's not uncommon.

 

Tony

[cereal tiller]

Easier no doubt and in the specific circumstances quoted probably the best of two evils BUT I think this is highly dangerous advice unless very heavily qualified - especially on a canal forum where metal boats are probably more than the norm and many boat builders seem to take delight it placing batteries under steel decking.

 

One slip of the spanner when removing positives first on many metal boats will get you a dead short and on a number of occasions I have seen the results where that ended up with exploding batteries. The equation is risk wrecking £2000 of equipment which seems to have been poorly wired or risk your eyesight.

 

It is up to each of us to draw our own conclusions - especially for anyone with isolators in the positive.

 

when i was an apprentice(sometime after the romans left)i rounded off a nut,i told the tutor that the spanner had"slipped",his reply was (YOU MEAN YOU ALLOWED IT TO SLIP!)

eventually....it sunk in!

 

one should be careful,experienced or not...

[Arthur Brown]

B&Q do some ranges of spanners with plastic covering,-which helps avoid accidental shorts to the chassis, If you wear rings then wear gloves to work on the battery, If you short battery to ground through the ring your finger will cook and need amputating.

[ditchcrawler]

B&Q do some ranges of spanners with plastic covering,-which helps avoid accidental shorts to the chassis, If you wear rings then wear gloves to work on the battery, If you short battery to ground through the ring your finger will cook and need amputating.

Metal straps on wrist watches are another danger, just behind things in your top pocket.

[Malarky]

hi all,i am contemplating replacing my battery bank before winter and was wondering if any one had any tips ie.do's and donts,for a person who has never done this operation before.i would say its a pretty standard setup as in 4 110ah leisure,1 starter,sterling battery charger and invertor,2 alternators.is there a sequence i should follow or just rip em' out and stuff the new ones in[if ya' know what i mean].allso i read here somewhere that when you buy new batteries that sometimes they can have dud cells,how do i ensure against this when i go to buy new ones.i was just going to replace them with the same ones that came with the boat,which i am pretty sure are just standard exide car batteries.they have lasted over four and a half years liveaboard (genny charging and no landline).so i dont see the point in fixin' what is not broken.am i mistaken?

thanks in advance.

First thing to mention is to make sure the connections are securely connected to the terminals when fitted. I have recently found a narrow boat yard that has an undisclosed policy of loosening the terminals as part of the service, and the result is a battery change once a year as standard!

It can also show a battery is knackered when the plastic sides bow out of true.

[Ex- Member]

Hi all

 

Rather than start a new thread.

 

Can anyone tell me the correct nuts to use on the US2200 volt 232 amp battery, they already come with threaded studs, however a standard M8 nut will only fit on the to the depth of the nut, so it's very close to 8mm, I'm unsure of the thread size as well, I would say it was coarse thread.

 

A chart I found equates M8 to US 3/8 - 16 UNC The batteries are made in the US. can anyone confirm this is correct.

[Grace and Favour]

Hi all

 

Rather than start a new thread.

 

Can anyone tell me the correct nuts to use on the US2200 volt 232 amp battery, they already come with threaded studs, however a standard M8 nut will only fit on the to the depth of the nut, so it's very close to 8mm, I'm unsure of the thread size as well, I would say it was coarse thread.

 

A chart I found equates M8 to US 3/8 - 16 UNC The batteries are made in the US. can anyone confirm this is correct.

 

You might have to telephone your battery supplier tomorrow morn . . . . . . . .

[Ex- Member]

You might have to telephone your battery supplier tomorrow morn . . . . . . . .

 

Think so, although I doubt they'll know

 

No mention of size on the US battery site. I'm pretty sure its 3/8 - 16 UNC. The 16 denotes the amount of threads per inch which I've checked and is correct. 3/8 does equate to around 8mm so I'll take a punt on that, just a couple of quid delivered for 10 x A2 stainless steel. Just handy if someone could confirm

Edited May 11, 2012 by Julynian

[smileypete]

Think so, although I doubt they'll know

 

No mention of size on the US battery site. I'm pretty sure its 3/8 - 16 UNC. The 16 denotes the amount of threads per inch which I've checked and is correct. 3/8 does equate to around 8mm so I'll take a punt on that, just a couple of quid delivered for 10 x A2 stainless steel. Just handy if someone could confirm

Maybe check that both + and - are 3/8, they may be different sizes.

 

Also a T-bar/socket combination with plastic head and heatshrink on shaft would be safer than a spanner for doing them up.

 

Quite a lot of useful info can be found on batt terminal nuts via a google discussions search.

 

cheers,

Pete. smpt

Edited May 11, 2012 by smileypete

[Ex- Member]

Maybe check that both + and - are 3/8, they may be different sizes.

 

Also a T-bar/socket combination with plastic head and heatshrink on shaft would be safer than a spanner for doing them up.

 

Quite a lot of useful info can be found on batt terminal nuts via a google discussions search.

 

cheers,

Pete. smpt

 

Hi Pete

 

Thanks for that.

 

The posts are all the same size, I've ordered some S/S nuts & washers. I'm pretty sure they'll be the correct size.

 

Good tip with the T-bar socket,

 

I'll take a look @ batt terminal nuts too.

 

 

 

 

[by'eck]

Hi all

 

Rather than start a new thread.

 

Can anyone tell me the correct nuts to use on the US2200 volt 232 amp battery, they already come with threaded studs, however a standard M8 nut will only fit on the to the depth of the nut, so it's very close to 8mm, I'm unsure of the thread size as well, I would say it was coarse thread.

 

A chart I found equates M8 to US 3/8 - 16 UNC The batteries are made in the US. can anyone confirm this is correct.

 

Nearest to M8 (standard 1.25mm pitch = 19.6 tpi) is 5/16" UNC - slightly courser at 18 tpi, & same as 5/16" BSW.

 

Check out & bookmark this excellent, comprehensive thread guide here

[Ex- Member]

Nearest to M8 (standard 1.25mm pitch = 19.6 tpi) is 5/16" UNC - slightly courser at 18 tpi, & same as 5/16" BSW.

 

Check out & bookmark this excellent, comprehensive thread guide here

 

Hi Richard

 

thanks, that's the guide I actually used, I've replaced the dead battery or my digital callipers so will be able to measure more accurately later.

 

 

[PaulD]

Metal straps on wrist watches are another danger, just behind things in your top pocket.

 

Battery And Inverter 10 commandments

 

1. Beware of the thunder and lightning that Lurketh in charged batteries, lest it cause thee to bounce upon thy buttocks in a most unseemly manner. Cause thee no spark or short among them.

2. Again, again I say unto you, Underestimate Not the energy of a shorted battery, for if thou so doest, thy friends will surely be buying beers for thy lady and consoling her in certain ways not acceptable to thee.

3. Suffer thou any DC installation doth comply with ABYC and or suffer Mightily Of The Plague of Lawyers who will separate thee from thy worldly goods .

 

4. Remember to put in Parallel or Series only Batteries of the same type, age, size, weight and state of charge or suffer thou a Righteous Ream Job by thy Supervisor, and the miraculous Shrinking of thy Wages.

5. Tarry thou Not amongst fools that mixeth different Types of Batteries in a Bank, for they are disbelievers but make question of them if their Airplane hath different size wings also.

6. Take care when thou takest the measures of high-voltage circuits, or thou shalt incinerate both thee and thy test meter. Verily, thou hast but small value and can be easily replaced, but the loss of a fine test meter bringeth much woe and lamenting back at the shop.

7. Bypass thou not fuses, breakers, or safety devices, nor wire thy vessel if thou be color-blind for this can arouse any Survivors to Wrath, and thou shalt suffer severe beatings and Loud Doubts on thine Ancestry, Present Worth and Future Prospects.

8. Covet not thy neighbors true RMS meter and Suffer thou learn well the common, neutral, negative, ground, earth and bond. Amen, Amen I say unto thee, the Smoke pouring out your ears cannot be putteth back and thy Brain worketh not a toss without it.

9. Bedeck thyself not with jewelry or watches whilst working with Acid and Lead substances lest thou compete with Quasimodo on the ugly scale and thy Wife will have no further use for thee except for thy Wages.

10. Give lasting peace, even amongst the Unbelievers, by letting them wire up their own Electric Toilet.

 

The old ones are the best, Paul

[Chris Pink]

Hi Richard

 

thanks, that's the guide I actually used, I've replaced the dead battery or my digital callipers so will be able to measure more accurately later.

 

 

You will have sorted this by now Mr Julyian but for others; they are indeed 5/16" UNC -true for trojan and other 6v trojan copiea - and a pox on the standards makers that made this different from 5/16" whitworth, and the mericans for not using M8