240 watts of solar not managing fridge ?

grafozz

grafozz

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With 2x80 watt and 2x 40 watt solar panels I still find the regulator warning buzzer going off , during the night because the fridge is left running (+ 1 x led anchor light ) .
the fridge draws 0.9 amps so even at 1.0 amps it is only drawing 24 amps per day with less for cycling .

the solar panels are putting in at least 50 amps per day ( Ionian ), so there should be a surplus ?

the 4 x batteries were new last winter , 4x 85 amp deep cycle , 1x 6 amp , 1x 8 amp regulators , I dont see where the deficit is ,

there is a second fridge on board but I dare not even think about turning that on !
Can someone throw some light on this for me , please ?
 
Perhaps you are getting too much information? You seem to have more than enough power, both storage and solar input. :confused:

Although the batteries are new, do they have the correct levels of electrolyte, have you checked?

Have you used a decent AVO to check the real voltage across the house batteries whilst the 'low battery alarm' is sounding? Check each battery by disconnecting one from the other as a faulty battery can drag down the voltage.

That would be my first step. ;)
 
Last edited:
grafozz said:
With 2x80 watt and 2x 40 watt solar panels I still find the regulator warning buzzer going off , during the night because the fridge is left running (+ 1 x led anchor light ) .
the fridge draws 0.9 amps so even at 1.0 amps it is only drawing 24 amps per day with less for cycling .

the solar panels are putting in at least 50 amps per day ( Ionian ), so there should be a surplus ?

the 4 x batteries were new last winter , 4x 85 amp deep cycle , 1x 6 amp , 1x 8 amp regulators , I dont reedsee where the deficit is ,

there is a second fridge on board but I dare not even think about turning that on !
Can someone throw some light on this for me , please ?
Click to expand...
How do you measure the amps, a smart meter.?
 
In the ionian this time of year you shoul be making 100AHrs+ on 90% of the days.
Either the batteries are stuffed, or something is wrong with the solar system.

A good battery monitor will tell you what the solar panels are doing. If you have not got a battery monitor install one. If you really object to a battery monitor a clamp on multimeter will at least verify the solar output, together with a regular multimeter to check the voltage.
If the output of he solar panels is OK do a load test on he batteries.
 
noelex said:
In the ionian this time of year you shoul be making 100AHrs+ on 90% of the days.
Either the batteries are stuffed, or something is wrong with the solar system.

A good battery monitor will tell you what the solar panels are doing. If you have not got a battery monitor install one. If you really object to a battery monitor a clamp on multimeter will at least verify the solar output, together with a regular multimeter to check the voltage.
If the output of he solar panels is OK do a load test on he batteries.
Click to expand...

Hence I asked - how does he measure the amps.

I would be very surprised if it used as little as .9amp, Mine uses 3 amps when running.

My fridge only runs about 15% of the time as I ripped out the old one, which used to run all the time and hardly get cold.

It could be a combination of factors -

Badly insulated fridge - 3 to 4 inches of insulation require all round.

Batteries have run down, and are only partly charged. - Needs a day on shore power to fully charge again.

Fridge taking more than .9amps.

If you don't have a good meter like the NASA BM1, then there is little you can do to really work out what its using and charging.
 
We are in the Ionian, we have 2 x100w solar panels, with 4 x 140 amp batteries. According to the Battery monitor we have never gone below 75%, normally not below 80%. We run a fridge, okay it is keel cooled, occasionaly use a slow cooker,computer and occasionally a t.v., aswell as anchor light.
Seems something is wrong with your system, may well bve just the alarm is not right.
Have you checked the state of charge of the batteries?
 
Check your batteries, one may have a shorted cell causing the rest to not fully charge and discharge prematurely.

Also, never go by the rating on the solar panels. If they're rated at 85watts you'll probably see an average of 80watts. And, depending on how the sun is, you will probably see less than that unless you have a solar panel sun tracking array on your deck.

My bet is with a shorted cell in one or more batteries causing your issue.

Unless you're running a 110volt fridge? If you are, that 1 amp x 110 volts is 110 watts. You might be lucky to get 1000 watts of power from your solar panels a day.

So, for the other 16hrs you aren't making power, you're using keeping that fridge cool.
 
solar / fridge

First , thanks all , its good to have your input .
1.batteries are sealed lead acid .

2. amps monitoring done by 2x BM1 . 1 per two battery bank.

3.each battery , disconnected ,tested at 1280/90

4.fridge is a Shoreline 100litre , Danfoss BD 35 compressor , 12volt ,2 years old , works fine , makes ice ,etc .the BM1 ,s show start up discharge at 1.6 amps , settling to 0.9 amps running on setting 1/2.

5 I checked the voltage output on the solar panels , the 80watts show20 volts and 3-4amps . best 5.5 amps. the 40watts show 19 volts and 0.40 amps , (these are older )

I have wired , only 2 weeks back , the fridge into the surplus charge terminal on the solara 135 regulator , now this runs the fridge without using the batteries , I gather , so they really should stay charged up ?

the boat happily sits in the sunshine every day , the panels get sun at different times , naturally , but as soon as I switch on a draw the monitors show discharge .

and no , I havent ever checked the system when the alarm goes off at 0330 ! I am
too hacked off to do anything logical at that time of night !

today I did switch on the second fridge at the same time and the amp draw was 1.6
for both fridges running .
the suggestion about the alarm being faulty was interesting and I would be very happy if this was the case , but the regulator that fires off is showing 25-75 % discharge at the same time so it seems to be working ok ?

still confused ...
 
grafozz said:
First , thanks all , its good to have your input .
1.batteries are sealed lead acid .

2. amps monitoring done by 2x BM1 . 1 per two battery bank.

3.each battery , disconnected ,tested at 1280/90

4.fridge is a Shoreline 100litre , Danfoss BD 35 compressor , 12volt ,2 years old , works fine , makes ice ,etc .the BM1 ,s show start up discharge at 1.6 amps , settling to 0.9 amps running on setting 1/2.

5 I checked the voltage output on the solar panels , the 80watts show20 volts and 3-4amps . best 5.5 amps. the 40watts show 19 volts and 0.40 amps , (these are older )

I have wired , only 2 weeks back , the fridge into the surplus charge terminal on the solara 135 regulator , now this runs the fridge without using the batteries , I gather , so they really should stay charged up ?

the boat happily sits in the sunshine every day , the panels get sun at different times , naturally , but as soon as I switch on a draw the monitors show discharge .

and no , I havent ever checked the system when the alarm goes off at 0330 ! I am
too hacked off to do anything logical at that time of night !

today I did switch on the second fridge at the same time and the amp draw was 1.6
for both fridges running .
the suggestion about the alarm being faulty was interesting and I would be very happy if this was the case , but the regulator that fires off is showing 25-75 % discharge at the same time so it seems to be working ok ?

still confused ...
Click to expand...

I looked up that compressor, and it looks like its amp consumption is around 2.5amps.

So why is your BM1 showing only 1 amp. Possibly your BM1's shunt is not having the total negative current go through it, therefore only reading 1/2???

There should only be 1 connection to your battery bank via the negative.

Just a thought............
 
How are your BMIs wired - if they are both monitoring the domestic bank, then you need to add together the current to get the total draw ( I'm not sure why you would have 2 on the domestic bank, but you imply they both show a current draw when the fridge is on)

Neil
 
If your fridge is wired to run off the 'surplus charge' output it shouldn't even be running at night ( no sun = no surplus ) The solar charge circuit may also have a separate voltage sensor circuit on it that cuts the supply at some silly voltage at 3am.

Your BM1 is either lying or you have it wired wrong. ( if you find 100litre fridge that can make ice on 0.9A I suspect everyone here will buy one )

Your 40 w panel/s ( is that current from both or each? ) appear to be producing less than 8w of power The 80's appear to be producing 60w ( again is that each or both )

Even if your current source figures are right you are still putting in about 50 A/hr per day so you should be able to drive a fridge all night.
 
BM1

Thanks , I had a thought after my last post , the reading on the BM1 is taken with the solar panels charging so its not a true reading of consumption , to find this the panels would need to be covered up , which I shall do tomorrow , then take a reading . this should give the actual amps draw without ant solar charge .
 
nimbusgb said:
If your fridge is wired to run off the 'surplus charge' output it shouldn't even be running at night ( no sun = no surplus ) The solar charge circuit may also have a separate voltage sensor circuit on it that cuts the supply at some silly voltage at 3am.

Your BM1 is either lying or you have it wired wrong. ( if you find 100litre fridge that can make ice on 0.9A I suspect everyone here will buy one )

Your 40 w panel/s ( is that current from both or each? ) appear to be producing less than 8w of power The 80's appear to be producing 60w ( again is that each or both )

Even if your current source figures are right you are still putting in about 50 A/hr per day so you should be able to drive a fridge all night.
Click to expand...

there are 2 batteries in each bank both have a BM1 monitor . total 4 batteries but different circuits , (2 engines ) the outputs I posted were regarding each solar panel (total 4 )

yes ,after sundown the batteries are running the fridge and they should mange 12 hours running it before the suns up again ?
 
grafozz said:
yes ,after sundown the batteries are running the fridge and they should mange 12 hours running it before the suns up again ?
Click to expand...

You'd certainly hope so! My 500Ah battery bank can run our 80l fridge (with same compressor as yours) plus tv, radio, lights and some other bits for 48 hours and only discharge to around 80%. Granted this was during a British summer, but you get the idea.
 
this is the Shoreline fridge

Key Features
12/24 Volt DC Fridge
845H x 501W x 540D mm
100 litres gross capacity
14 litre freezer box (-12c)
Interior light
Reversible door
Automatic defrost fridge section
Low Voltage Warning LED
All WHITE
2 glass shelves
30 Kgs
0.32 KWhr/24hr
1.14 Ahrs (12V)
Narrow - RR5010W
 
I also have doubts about the current drawn by your fridge, should be quite a lot higher than indicated. Also, no-one I know uses the output terminal on the solar regulators, most wire the fridge into the general circuit via a circuit breaker, battery banks paralleled.
 
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