Bernie and Carols Isuzu fit out.

[BernieQ2]

Tiz the weekend George having a rest . House reno got in the way .
later today I will post some more .
Bernie .

[Newcastle George]

Bernie, as I have the same (similar) fridge as you I have disconnected the solar from my batteries at 10:30 and have no load other than the fridge and inverter, I will be able to tell you how many ah they have drawn over 24 hours at nominal 24v when I check at 10:30 tomorrow. this may help.

My fridge is empty at the moment and set for 4.5* so may cycle more often than normal. The inverter, on standby is drawing 6 to 7 watts.
The fridge has started and the total draw is 109 watts.

George

[BernieQ2]

Its later . Mates battery was crap worse than mine so that didn't work . Was at rest 12.7 turned the fridge on and went to 12 .0 immediately.
So I think mine are on the way out work perfectly while the sun shines (as it does here) wouldn't like a trip down south in winter . I reconnected at 10.15 showing 12.6 now 10.45 and showing 13.2 with 14amps coming in its hazy today sorter like filtered sunlight . Will connect the fridge a bit later .
Cuppla pics the new cupboard's done and dusted and the blurb on my fridge .
Bernie .

DSCF2655 (Custom).JPG

DSCF2657 (Custom).JPG

Thanks George last pic is for you .

[BernieQ2]

test
Bernie .

[Newcastle George]

After 24 hours with only fridge connected to 260 ah of 24V battery. Victron BMV702 shows 26.6 ah consumed, capacity remaining 91.3%, battery voltage at rest 1 hour 25.35V (12.675), fridge temp min 2* max 6*.

George

[T1 Terry]

Terry I disconnected around 2pm the battery at 12.00v I don't think the inverter could turn the fridge on it was only showing 218vac . I held both door on the fridge open for 5 min and it didn't start .
The battery now at rest is 12.5 .
Mate up the road has lent me a AGM battery ( Ill tell him about it when he gets home next week ) so will also do test with this battery as well, I think its 100amp .
Bernie .
Read the blub on the inside of the fridge and it says 5amp draw ?

http://www.ozervnews.com/forum/download ... d=5908&t=1

This spec sheet indicates it is not an inverter type fridge so the start up current is high for a few secs max, I'm guessing this is why the fridge wouldn't fire up again once the voltage got low. There specified 1.095kWh for a 24 hr periods adds up to 91Ah @ 12v, probably calculated from the Aust Standards test when calculating the yrly consumption and star rating and that test is at an ambient of 36*C from memory, so it would be less than that in winter.
0.5 amps @ 240vac = 10amps @ 12v, so fairly close to the 7.5 amps you have recorded. Allowing 5 times the current load for start up gives a figure of around the 50 amp mark which is quite a solid draw for a lead acid battery at any time, so a weakened battery getting close to the 50% SOC would not be able to provide that sort of current draw without dropping below the inverter cut off voltage.... so that is likely why it could not restart.
Still watching with interest to see how well the sick battery recovers or if it does at all.
Just as a quick plug for lithium batteries, a 100Ah@12v would power that fridge in the tropics for 24 hrs without any issues and continue to do it for many yrs if there was enough solar to recharge it the next day, so 500w of solar with good sun input every second day or 500w even when it's raining would put some of that back each day and probably be enough for 2 or 3 days of rain before an alternate charging method was required.

T1 Terry

[BernieQ2]

Your quite ok Terry to use me as a free test bed if you wish...................hehe .
Had trouble today getting on (Lance disease)???
What I had done was turn the fridge on at midday yesterday @13.5v this morning at around 7.30 the batteries showed 12.5 they are back as one in parallel .At about a hour later they showed 13.4 with 14amps coming in . Now at almost 3.30pm the batteries show 13.1 with 8amps coming in the fridge is also cycling at this time . My fridge is also empty George , plus it has auto defrost . The system seems to be working better than it was .
Plus me being me mistook the gauge on the inverter its watts not amps and shows around 90w when the fridge is on , maybe some one can tell me what amps that is . I assume its around the 7amp that the clamp meter showed me.?
Bernie .

[T1 Terry]

Your quite ok Terry to use me as a free test bed if you wish...................hehe .
Had trouble today getting on (Lance disease)???
What I had done was turn the fridge on at midday yesterday @13.5v this morning at around 7.30 the batteries showed 12.5 they are back as one in parallel .At about a hour later they showed 13.4 with 14amps coming in . Now at almost 3.30pm the batteries show 13.1 with 8amps coming in the fridge is also cycling at this time . My fridge is also empty George , plus it has auto defrost . The system seems to be working better than it was .
Plus me being me mistook the gauge on the inverter its watts not amps and shows around 90w when the fridge is on , maybe some one can tell me what amps that is . I assume its around the 7amp that the clamp meter showed me.?
Bernie .

Look to see the voltage at the time, then divide the watts by that voltage and it will give you the amps at the time. The watts remain fairly constant but as the voltage drops the amps increase thanks to the inverter as it will keep the 240vac side at a constant voltage and use what ever it requires to produce that, all the way down to around 11v. At 13.5v 90w would require 6.6 amps but at 11v it would require 8.2 amps so you need to know the voltage at the time you read the watts to get a definite number of amps being used at the time.

T1 Terry

[BruceS]

So ................

Watts divided by Volts equals Amps.
Amps times by Volts equals Watts.
Watts divided by Amps equals Volts.
Volts times by Amps equals Watts.
etc?

[BernieQ2]

Thanks Bruce Terry George .
Batteries at 5.45am was 12.4 fridge was running . I can live with that. I will continue with bulk charge to 15v for a few more days .
Bernie .