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

[luggsy]

Battery's are at 93% and 13v according to the smart gauge I have had to turn the genny off at 8 pm out of respect for the other boaters moored near by also turned the freezer off

[nicknorman]

Battery's are at 93% and 13v according to the smart gauge I have had to turn the genny off at 8 pm out of respect for the other boaters moored near by also turned the freezer off

I would check the Smartgauge reading before you go to bed (presumably everything then off, except the fridge) and again when you get up. That will give a pretty good idea whether the batteries are goosed, but I would say they are or at least need an equalise.

[luggsy]

How much of 'all' your stuff is 240V? Fridge/freezer/cooking/kettle/washer/dryer/TV/Laptop/lights/pumps...

 

Richard

Hi Richard when we go to bed the only things that are on are the fridge 240v freezer 240v and inverter , we turn the TV & top set recorder off at the socket

[Bod]

As you can gather I know fxxk all about the electric side of things the boat is a new build ,I was advised to have 6 battery's with the set up we where having ie all 240 V and 400 w of solar , don't know about the victron being set up with a lap top I would of thought so as the man who did it seems to be very good at his job , I would like to disconnect 3 of the battery's but as it is only 4 months old I don't want to touch any of it as it may invalidate my guarantee and warrants

 

I think a trip back to the builder is in order.

To avoid looking a fool, (I know I've done it enough times!) make any normal checks first, fluid level in batteries, (if not sealed) tightness of all connections, alternator belt tension, etc.

 

Bod

NB If you can check the fluid level, then hydrometer readings may reveal a duff cell, or two.

[smileypete]

Nick has covered it pretty well, but just to repeat, if the batts seem to be losing capacity, ie powering things for less and less time:

 

1) What charge voltage is the genny charger or engine alt set to? 14.8V may be best (for short term off grid charging only), for calcium leisures, anything less may cause under-performance - despite what suppliers say.

 

2) What current are the batts taking when the Smartguage says 100%? The current should stabilise to a constant low level, typically less than 1% of batt capacity for calcium leisures. Always good to monitor current especially when charging at higher than recommended voltages as above.

 

3) How often are the batts charged to 100%? For batts in daily off grid use, at least weekly seems to be best.

 

Barring a serious batt cabling problem or faulty batch of batts, it may be the batts have been not quite well charged enough for the above reasons.

 

Unfortunately Smartgauge, though very good, is not a panacea - it helps avoid killing the batts quickly but doesn't show up other problems.

 

If this all sounds like gobbldygook then just take the boat back to the builder as Bod says. Might be worth considering an RCR boat maintenance course too, they should give a good grounding in electrics...

 

PS If CCing for some time from now, and the batts are kaput, maybe consider replacing with decent proper 'semi traction' batts from the likes of Trojan, and their T105s, but only if they can be charged and equalised at the required voltages.

 

cheers, Pete.

~smpt~

Edited December 22, 2014 by smileypete

[luggsy]

I will be taking the boat back after the new year, just wanted some ideas as I could be told any old tales at least now I have a better idea but I knew things where not right , also I know it won't be a problem taking it back and getting it sorted thanks to every one for your input I will keep you up dated ( tomorrow ) lol

[RLWP]

Hi Richard when we go to bed the only things that are on are the fridge 240v freezer 240v and inverter , we turn the TV & top set recorder off at the socket

 

I'm curious about how much of your stuff needs an inverter to work

 

Richard

[luggsy]

I'm curious about how much of your stuff needs an inverter to work

 

Richard

TV set top box ( recorder ) Central heating pump for the lockgate freezer & fridge

[RLWP]

Thanks, that should help the electrical bods to do an estimate of your power consumption

 

Richard

[nicknorman]

TV set top box ( recorder ) Central heating pump for the lockgate freezer & fridge

Just as a comparison, we have 450AH of Trojan batteries, a mains 22" tv & humax HD recording satellite box, we like the boat well lit (by LED lighting), a 12v shoreline fridge. In winter when we stop early (15:30) and have lighting on from 16:00, tv/satellite on for most of the evening, go to bed around 23:30, have the electric blanket on all night (on low) with the batteries very cold (hence reduced capacity) and thus leave the inverter on all night, by getting up time the next morning the Smartguage is in the low 60s%. It probably only drops 5-7% overnight despite having the electric blanket on.

[RLWP]

Electric blanket! My contempt is being severely stretched tonight

 

Richard

[nicknorman]

Electric blanket! My contempt is being severely stretched tonight

Richard

Best thing we ever bought. It's thermostatic so just keeps the chill off on "low", so when you roll over you don't hit a cold spot, and don't need a heavy winter duvet.

 

Mind you the one in the house is slightly better since it has 2 zones ie each can have his own setting. No more fighting about setting #2 vs #3! Trust me, they make for a great night's sleep.

[RLWP]

Anyway.....

 

ISTR we have discussed the power consumption of fridges running on 240v through an inverter before

 

Richard

 

I've sprained my contempt

[nicknorman]

I've sprained my contempt

Ah well, the inflammation will help to keep you warm despite your lack of an electric blanket.

[dor]

I will be taking the boat back after the new year, just wanted some ideas as I could be told any old tales at least now I have a better idea but I knew things where not right , also I know it won't be a problem taking it back and getting it sorted thanks to every one for your input I will keep you up dated ( tomorrow ) lol

 

Don't be too surprised if you find the "three year warranty" or whatever period doesn't cover your goosed batteries if it is all down to sulphation. The warranty is against defects, not against misuse.

[ditchcrawler]

overnight despite having the electric blanket on.

We have one, not as posh as yours and only use it on the first night aboard this time of the year. We find it takes about 24 hrs to warm the boat through when its been left for a couple of weeks or more. Again like you we have 4 T105 Trojans that have just passed 4 years old, but no smart gauge.

[Alan de Enfield]

To the OP

 

I would suggest that 4 or 5 hours charging with either a 100 amp alternator or battery charger will be in no way long enough to get 800Ah of batteries from 50% to 100%.

 

It is a mistaken belief that a 100 amp alternator / charger will provide you with 100 amps - an alternator in may need 6000 rpm to achieve anything like that output and get to those speeds needs careful matching of pulleys - I believe that normal pulley matching is 3 to 1 and if yours is at this ratio you will need to be running your engine at 2000rpm.

 

Secondly, an alternator will only put out its 'maximum' charge for a short time (this is due to battery chemistry, a battery will control the alternator output, not the other way around)

You need to get 400 amps back in your battery.

 

Hypothetical figures but are not an unreasonable example.

First hour alternator output 100 amps

Next hour alternator output 70 amps

Next hour alternator output 40 amps

Next hour alternator output 20 amps

Next hour alternator output 6 amps

 

After four and a half hours you have actually replaced 236 amps.

 

I would be guessing that you have destroyed you batteries with undercharging and that the Smartgauge has got confused / reset to the now much lower battery capacity.

 

Top answer the original question 800 amps is 'way to much' , a fridge and freezer will take roughly 100Ah over 24 hours - your problem appears to be replacing what you have used, or a 'leaky' battery(s)

 

Do you have any other 'thirsty' items ?

Microwave ?

Washing Machine ?

etc

 

Turn everything electrical off for an hour, see what you Smatgauge is showing, then check the actual batteries with a test-meter, compare test meter voltage results to the following, table, and then compare the table "SOC" to the Smatrgauge SOC, This will not show if you have a reduced capacity, but it will show if the capacity you have left is charged.

 

Edited December 23, 2014 by Alan de Enfield

[system 4-50]

OP - Have you always checked your SG daily or is this a new practice? In other words, were you undercharging for a period before you started checking?

[nicknorman]

 

It is a mistaken belief that a 100 amp alternator / charger will provide you with 100 amps - an alternator in may need 6000 rpm to achieve anything like that output and get to those speeds needs careful matching of pulleys - I believe that normal pulley matching is 3 to 1 and if yours is at this ratio you will need to be running your engine at 2000rpm.

We do get a lot of these type of posts on here. It is the classic pitfall (into which we all fall, including myself) of presuming that everyone else's installations exhibit the same characteristics as our own. I don't know what a modern Barrus Shire is like for pulley ratios, but a modern Beta has good pulley ratios such the the large (175A) alternator will produce full output at just above idle. Maybe 150A at idle (850rpm) and the full amount by 1000rpm. Of course the best way to know this is to have means of measuring charge current.

[Markinaboat]

IMHO - Just a thought, does the Smartgauge have to be setup with the total AH of the batteries in the bank? i.e. you added a battery/ies but does the Smartgauge know that or is it still calculating on the previous total AH? Maybe a possible test would be to let the batteries run down until the inverter says no (should cut out 240v if unable to deliver) and check the % status at that point. It should be in the region of 40% but a higher reading could indicate a miscalculated reading.

[nicknorman]

 

Secondly, an alternator will only put out its 'maximum' charge for a short time (this is due to battery chemistry, a battery will control the alternator output, not the other way around)

You need to get 400 amps back in your battery.

 

Hypothetical figures but are not an unreasonable example.

First hour alternator output 100 amps

Next hour alternator output 70 amps

Next hour alternator output 40 amps

Next hour alternator output 20 amps

Next hour alternator output 6 amps

 

After four and a half hours you have actually replaced 236 amps.

 

I would be guessing that you have destroyed you batteries with undercharging and that the Smartgauge has got confused / reset to the now much lower battery capacity.

 

 

This is of course true, but the degree to which it is an issue depends on battery size vs alternator size. In the case of the OP, when the batteries had full capacity they were pretty big compared to the charging capability so I think max current would be sustained for longer. Of course now they are way down in capacity only 200AH has to be replaced anyway.

 

I agree the batteries have probably been undercharged since when the Smartgauge just reaches 100% there is still a little way to go, and such batteries seem to need a high charge voltage, or fairly regular equalisation.

IMHO - Just a thought, does the Smartgauge have to be setup with the total AH of the batteries in the bank? i.e. you added a battery/ies but does the Smartgauge know that or is it still calculating on the previous total AH? Maybe a possible test would be to let the batteries run down until the inverter says no (should cut out 240v if unable to deliver) and check the % status at that point. It should be in the region of 40% but a higher reading could indicate a miscalculated reading.

No, the Smartgauge does not need to be told the total AH. It works in relative terms eg 60% SoC indicated, is 60% of whatever the current actual capacity is. If you add or remove batteries, the SG will automatically adapt within a couple of cycles.

[spadefoot]

Is there any chance that there is a battery-inverter-charger-battery loop going on?

[nicknorman]

Is there any chance that there is a battery-inverter-charger-battery loop going on?

Doubt it. I think the OP has a Victron Combi which is either in inverter mode, or charger mode. It will only be in charger mode if there is external ac present, either from shore power or a genny.

[luggsy]

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

[bottle]

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

 

or

 

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

 

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)

 

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