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

[Sabcat]

Quick up date still in marina on shore power due to Harecastle tunnel being closed ,so to test the victron I disconnect from shore line at 9 pm 1st night smart gauge showing 99% 12.65v victron showing 97.1% & 12.62 at 11.45 pm , at 8.30am smart gauge showing 71% & 12.24 v victron showing 91.8% & 12.23v so a big difference on s o g need to get out cruising to test proper , will up date once out cruising , just to add 240v fridge 240v freezer and 240v central heating pump on all night

 

That to me says your batteries are well past their best. The Victron is just counting the amp hours out of the batteries and subtracting them from the capacity you told it the batteries have while the SG is monitoring the batteries based on their actual remaining full capacity and telling you have 71% of that left.

[bottle]

Quick up date still in marina on shore power due to Harecastle tunnel being closed ,so to test the victron I disconnect from shore line at 9 pm 1st night smart gauge showing 99% 12.65v victron showing 97.1% & 12.62 at 11.45 pm , at 8.30am smart gauge showing 71% & 12.24 v victron showing 91.8% & 12.23v so a big difference on s o g need to get out cruising to test proper , will up date once out cruising , just to add 240v fridge 240v freezer and 240v central heating pump on all night

 

The voltage readings, if they are no load, batteries rested readings, suggest that the batteries are at just above 50%SOC.

 

Otherwise as Sabcat says the Victron has not been given the correct capacity of your batteries, not what the label says, what they actually have.

[luggsy]

The voltage readings are under load ie fridge freezer central heating pump all 240 v on

[bottle]

That would expalin the 'low' readings.

 

Trust the Smartgauge but remember it is only accurate when the batteries are at rest or being discharged.

[luggsy]

Could I just turn all the power items off and leave them off for a hour or so to get a true reading of the Batteries ?

[bottle]

The voltage readings would then give you an idea of their SOC, it would not tell you their capacity.

 

If the Smartgauge has been through a few cycles ( battery charging and then discharging) it will be accurate.

[Paul C]

Surely its a simple excercise to do a "backsolve" style configuration, and iteratively keep trying capacities in the Victron until the Victron and Smartgauge show the same state of charge?

Edited January 28, 2015 by Paul C

[bottle]

Yes but as the batteries age further the Victron will again go out of 'sync' (true reading) whilst the Smartgauge will continue to be correct until the batteries are at less than 50% of their original capacity and then it to will be inaccurate.

[nicknorman]

Yes but as the batteries age further the Victron will again go out of 'sync' (true reading) whilst the Smartgauge will continue to be correct until the batteries are at less than 50% of their original capacity and then it to will be inaccurate.

The victron says ~8% has been used whilst the SG says ~29%, so the batteries are already well below 50% of rated capacity, nearer 25%. Presuming the Victron is wired correctly to measure all current coming out of course.

[Bob Blues]

two things, Is your Charger set up for the correct batteries?

second I saw you had a clamp meter on order. I got one and found out my mastervolt was nadged as with the inverter on and nothing connected it was drawing 10A from the battery.

Worth a check....

 

Bob

[luggsy]

Is there any electrical experts willing to show me how to use a clamp meter and look at my battery set up ? I am at Stoke at the minute and will be until Harecastle tunnel is opened ( 16 th feb ) I will then be making my way up the t & m to the middlewich branch then down the Llangollen , obviously you will be paid

[Paul C]

Is there any electrical experts willing to show me how to use a clamp meter and look at my battery set up ? I am at Stoke at the minute and will be until Harecastle tunnel is opened ( 16 th feb ) I will then be making my way up the t & m to the middlewich branch then down the Llangollen , obviously you will be paid

 

Let us know if/when you'll be at Barbridge - Hurleston area.

[blackrose]

Personally I've never understood the logic of using batteries to keep large amounts of food frozen on a boat. I realise we all do things differently, but as a liveaboard it seems unnecessary to me. The trick on boats is to reduce demand from the batteries, then you're not constantly chasing it (and replacing batteries).

Edited January 29, 2015 by blackrose

[Phil Ambrose]

I find the demands of my stomach quite compelling, (we have a freezer)

Phil

[Bod]

I fear the difficulty is that Amp counter type meters rely on you telling them what is the actual capacity of the battery. But as this changes with time, and is all but unmeasurable, then accuracy, suffers badly the further away from new the batteries are.

Smart Gauge tells you how much capacity your batteries have remaining to be used. But not the starting point for that calculation.

 

When my batteries started to fail, the Smart Gauge, went down quickly, but with charging went up quickly.

I reckon that if Smart gauge goes Down quick...Up quick = Batteries naff.

Down quick...Up slow = Heavy drain

Down slow....Up quick = Light drain

Down slow....Up slow = Poor charging

 

Bod

[nicknorman]

I fear the difficulty is that Amp counter type meters rely on you telling them what is the actual capacity of the battery. But as this changes with time, and is all but unmeasurable, then accuracy, suffers badly the further away from new the batteries are.

Smart Gauge tells you how much capacity your batteries have remaining to be used. But not the starting point for that calculation.

 

When my batteries started to fail, the Smart Gauge, went down quickly, but with charging went up quickly.

I reckon that if Smart gauge goes Down quick...Up quick = Batteries naff.

Down quick...Up slow = Heavy drain

Down slow....Up quick = Light drain

Down slow....Up slow = Poor charging

 

Bod

Well put, have a greenie!

[luggsy]

Let us know if/when you'll be at Barbridge - Hurleston area.

Will do thanks

[luggsy]

Just checked the smart gauge as yesterday it was showing 97% soc it's still on 97% soc even though we are on shore line , what's going on ?

[blackrose]

I find the demands of my stomach quite compelling, (we have a freezer)

Phil

I have a small tabletop freezer too but I only use it while on shore power. If I was living off grid I wouldn't bother with it. There was plenty of fresh food in the shops the last time I looked.

Edited January 29, 2015 by blackrose

[nicknorman]

Just checked the smart gauge as yesterday it was showing 97% soc it's still on 97% soc even though we are on shore line , what's going on ?

Maybe the charger has gone into float a little prematurely. At a voltage of around 13.25v there may not be any current going into the batteries. If you briefly disconnect the shore power and reconnect it, that will put the charger back into bulk and then absorption mode (ie a higher voltage) for a while.

[luggsy]

Ok thanks nick

[peterboat]

I have 1500 ah of traction batteries charged by 1kw of solar due to lack of sun recently I have been down on voltage the whispergen runs twice a day but hasnt gone into float for weeks its always on bulk. The other day even with the engine running it still stayed on bulk its a clever device so it must know that the batteries are still demanding power even though the voltage is up at 13.6. I did a New Year cruise clocking up 6-7 hours a day and that put the whispergen in float so it does go to show how much cruising you need to charge cold batteries ps 160 leisure alternator

 

Peter

[Phil Ambrose]

I have a small tabletop freezer too but I only use it while on shore power. If I was living off grid I wouldn't bother with it. There was plenty of fresh food in the shops the last time I looked.

Not wishing to make an issue of this but shops are very thin on the ground here so we always stock the 12v undercounter freezer so when we cruise we are not reliant on finding pubs which are also thin on the ground. I realise are chosen method of cruising for about a week at a time means we can adopt a different stance on the fridge and freezer front. If we were CCing I may well have a different view on this matter.

Phil

[bottle]

I have a small tabletop freezer too but I only use it while on shore power. If I was living off grid I wouldn't bother with it. There was plenty of fresh food in the shops the last time I looked.

 

and so there is but I hate shopping and so do it as little as possible. ie. once a week or at even greater time intervals

 

Full size fridge and full size freezer.

Edited January 29, 2015 by bottle

[Sabcat]

 

and so there is but I hate shopping and so do it as little as possible. ie. once a week or at even greater time intervals

 

Full size fridge and full size freezer.

 

I'm with you there. Shopping is grim. Get in, stock up, get out. I've got a proper full size freezer and a proper full size fridge to go with it. None of those Mickey Mouse 12v jobs on here