Is 805 AMPs enough to run 240 v fridge & 240 v freezer

[RLWP]

Just in case - the solution to this problem is very unlikely to be adding more batteries to your existing bank

 

Richard

[nicknorman]

Just a quick up date wife had not turned freezer off ( just turned to the lowest setting by mistake ) so the battery's where 44% & 11.90v at 8 am so from 8 pm to 8 am 48% has been used , I will turn the freezer off myself tonight and get the battery's to 100% by the smart gauge , I would of thought that the battery's would of been fully charged after 10 or 11 weeks on shore line , the first week that we had away the battery's where only just over the 50% in the morning that's why we ended up buying a genny

For the sake of £30 I suggest you get yourself a clamp-meter such as UNiT-203 - eBay, or Maplins for a bit more, but if you get a different model check is does DC current since plenty don't. An ideal last minute Christmas present, even if only for yourself!

 

That way you will know how much current you are draining at any one moment, so will be able to rule out (or not) some additional power drain that you forgot about. They are also useful to determine when to stop charging (tail current). The Smartgauge is very good on discharge, less good on charge. Whilst I agree that you should consult the builder regarding this problem, eventually you are going to have to get a grip of such things yourself, and trying to sort electrics without adequate measuring equipment is like trying to spanner your engine blindfolded. Lecccy is invisible!

 

I would also want to use the voltmeter (either in the Smartgauge or your new DVM) to ensure the charging voltages are appropriate.

Edited December 23, 2014 by nicknorman

[luggsy]

Yes, batteries were probably at 100% SOC when you left but after one day or even less they would not be.

 

If the batteries are/have failed it is because of less than perfect charging. Batteries can be ruined in less than than a week if not charged correctly

Well I never knew that I always thought you had to run a battery down the charge back up

or

 

you have another heavy use of electricity that you do not know about.

We have a 750 w microwave but only ever use it with the engine running once a week

or

 

the charging system is not set up correctly, causing early demise of batteries.

 

 

Basically you are using 50% of the batteries capacity (present day, not what they were when new) in 12 hours (20:00 hrs to 08:00 hrs)

 

My usage is about the same (mains TV, freesat box, fridge, freezer and LED lighting) but as I said before my batteries are well past their best, as it now looks like yours are.

 

That means your bank and mine are now at about the same capacity. (not State Of Charge)

I thought you was talking money bank at first lol

Battery bank: 330 amp.hrs @ 24v equivalent to 660 amp.hrs @ 12v

[cuthound]

Assuming that the batteries are suffering from sulphation, and not from a dodgy cell (and this hasn't been proven yet), the sulphation can probably be reversed by giving them a very low charge for a long time. As the batteries are relatively young the lead sulphates crystals should be fairly small and thus convertable back to lead when charged at a low rate (well below gassing point for wet cells).

 

Certainly worth a try before buying new batteries.

[luggsy]

Battery's are on charge , clamp meter ordered thanks for all the info

[J R]

A new battery should never be added to an 'old' battery bank as this will cause problems. Suggest you use a drop tester on each battery to see if there is one that is faulty. If you have wet open batteries, make sure that the electrolite is up to the correct level.

[luggsy]

A new battery should never be added to an 'old' battery bank as this will cause problems. Suggest you use a drop tester on each battery to see if there is one that is faulty. If you have wet open batteries, make sure that the electrolite is up to the correct level.

What's a drop tester ?

[Keeping Up]

A new battery should never be added to an 'old' battery bank as this will cause problems. Suggest you use a drop tester on each battery to see if there is one that is faulty. If you have wet open batteries, make sure that the electrolite is up to the correct level.

Not true, it won't cause any problems unless one of the existing batteries has a shorted cell.

[luggsy]

Battery's showing 100% & 13.10 v on the smart gauge , freezer off will see what tomorrow brings

[RLWP]

Place your bets, Ladies and Gentlemen

 

Richard

[ditchcrawler]

Battery's showing 100% & 13.10 v on the smart gauge , freezer off will see what tomorrow brings

How long after the charging stopped did you read 13.1 volts, or was it while the charger was running?

[luggsy]

Straight after , I will check it before I go to bed

[Drayke]

Not sure if this has been suggested but, do you have a calorifier that has an immersion heater in it and has this been left switched on, just a thought.

 

Fred

[luggsy]

Not sure if this has been suggested but, do you have a calorifier that has an immersion heater in it and has this been left switched on, just a thought.

 

Fred

Yes checked that I was told it will only work when on shore power or genny

11.30 smart gauge is reading 92% & 12.50v freezer is defiantly off

[dor]

Yes checked that I was told it will only work when on shore power or genny

11.30 smart gauge is reading 92% & 12.50v freezer is defiantly off

 

Three possibilities: Smartguage is lying and you were not at 100%; the 13.1 is to be expected just after stopping charging, should drop to about 12.8 after an hour or so with minimal current draw if batteries are 100% (of their now possibily depleted capacity).

 

One or more batteries have a shorted cell so are only 10.4V batteries and are pulling the others down.

 

Batteries are goosed, due to not being completely charged to a genuine 100% often enough.

 

My money is on number 3, as it is so common due to people thinking their 100A alternator delivers 100A so only takes a couple of hours or so to fully recharge their 440AHr bank, as opposed to the 10+ hours it needs in reality. You really do need a half-decent digital ammeter in your system. Or preferably more. I can see what current I am drawing through 12V, what current I am putting into or out of the batteries in total, what current my solar panel is delivering, and by comparing one and two, what current my inverter is drawing.

[RLWP]

Scenario 2 should show up as a warm battery

 

Richard

[Alan de Enfield]

Just thinking about this -

 

A fridge (or freezer) takes very little overnight, the doors are not opened and therefore the motor does very little 'cycling', maybe the actual capacity of the batteries is lower than we think.

 

If a freezer is using 50 ah per day I would hazard a guess that only about 10 ah is used overnight.

[Robbo]

Yes checked that I was told it will only work when on shore power or genny

11.30 smart gauge is reading 92% & 12.50v freezer is defiantly off

12.5v is around 80% soc.

[bottle]

Yes but we do not know if anything else was working or how long the batteries had rested before the reading had been taken.

 

The percentage (Smartgauge) could be correct but the voltage was held down by other factors and would recover after any load was OFF and the batteries rested.

[nicknorman]

12.5v is around 80% soc.

Only with zero load. Which was not the case here I suspect.

[dor]

Only with zero load. Which was not the case here I suspect.

I thought the whole point was to take the reading after resting with zero load...

 

What actually got used between turning off the charger and the later reading?

[RLWP]

I thought the whole point was to take the reading after resting with zero load...

 

Not easy to achieve at night

 

Richard

[chubby]

Not really qualified as such to give advice but something i think people may do is look at smartgauge SOC climbing up & up . It hits 100 & they turn the engine off . During my research before buying a smartgauge & since & due to recent probs i ve read a good deal of old threads on here & elsewhere on tinter & my understanding is that you ought to keep charging

for some time after 100 SOC is achieved .

I m not saying thats what s happened here , but maybe .

cheers

[luggsy]

8 amThis morning smart gauge is showing 35% & 11.85v only thing on was the fridge, so not much difference

[Robbo]

8 amThis morning smart gauge is showing 35% & 11.85v only thing on was the fridge, so not much difference

 

When charging your batteries, keep feeling the temperature of each battery, if one feels hot or a lot warmer than the others, remove this battery. When you get your clamp meter this will show you how many amps you are pulling at that moment in time. Unfortunately unlike a battery monitor like a Victron/NASA it won't show you how many ah's (how many amps over a period of time) have been used.

Edited December 24, 2014 by Robbo