Setting leisure battery voltage correctly

15Degrees

Free Member
Joined
Dec 15, 2018
Posts
32
Likes collected
8
Location
Corby
Funster No
57,595
MH
Burstner Argos 747-2
Exp
I'm a Newbie
Hi Guys

In My Burstner Argos I can set the leisure battery amps on the main panel. The thing is if I set them to 220 (They are 110 each) then it shows max 100% at 176amps

Is that correct? As of course 176 is not 220? I tried changing them to 230 and it bumped up a bit to 184 at max 100%

Bit confused with this? Should it not show max 100% 220?
 

hilldweller

LIFE MEMBER
Joined
Dec 5, 2008
Posts
615
Likes collected
36,112
Location
Macclesfield
Funster No
5,089
MH
Zilch Mk1
Exp
From Aug 2007
Don't expect mathematical accuracy. Just a reasonable guide.
 

scotjimland

LIFE MEMBER
Joined
Jul 25, 2007
Posts
2,655
Likes collected
11,809
Funster No
15
MH
None
You have a total capacity of 2 x 110 ah = 220 ah

For longevity and to prevent damage to the batteries they shouldn't be discharged below 50% of total capacity..

so you have a useful capacity of 110 ah

The panel reading is misleading

Voltage is a better guide to remaining capacity .. do you have a voltage panel meter ?

dsc-marine-electrical-systems-seminar-020311-44-728.jpg
 

andy63

Free Member
Joined
Jan 19, 2014
Posts
4,672
Likes collected
15,019
Location
south shields
Funster No
29,767
MH
None
Exp
since 1990
Hi Guys

In My Burstner Argos I can set the leisure battery amps on the main panel. The thing is if I set them to 220 (They are 110 each) then it shows max 100% at 176amps

Is that correct? As of course 176 is not 220? I tried changing them to 230 and it bumped up a bit to 184 at max 100%

Bit confused with this? Should it not show max 100% 220?

If you are talking about some sort of battery monitor function or panel then yes ..you normally set your battery capacity in amp hours... unless you know your batteries are new and in good shape then it may be better to enter a lower amp hour capacity than that stated... it drops over the life of the batteries anyway..
That will most probably give a more realistic read out of the capacity available...
The net amps used is usually a resetable figure... normally set at zero from a known point...ie batteries fully charged...
As said its not an exact science ...and requires altering from time to time to make the displayed capacity meaningful...
Andy..
 
OP
OP
15Degrees

15Degrees

Free Member
Joined
Dec 15, 2018
Posts
32
Likes collected
8
Location
Corby
Funster No
57,595
MH
Burstner Argos 747-2
Exp
I'm a Newbie
No im talking about does it matter.

Does it matter if you set them to 220 or 495>! Does that alter how they are charged for example. Logically I should set them to 220 as that's what they are when joined together

BUT

At this setting (220) it displays a 100% charge as 176ah as I said.

So i was trying to understand it and Why it displays only 176 when fully charged and why that figure goes up if I set them to 230 etc.
 

andy63

Free Member
Joined
Jan 19, 2014
Posts
4,672
Likes collected
15,019
Location
south shields
Funster No
29,767
MH
None
Exp
since 1990
it does appear that altering the ah capacity alters the display for the available capacity and you will have to try and select a figure that is meaningful for your batteries... so that what you see is what you get ...
I have a seperate battery monitor and as i said i can reset the net amps in or out to zero from the known fully charged point..

Does that alter how they are charged for example.

I doubt it..

Andy

Subscribers  do not see these advertisements

 
Joined
Jan 29, 2017
Posts
718
Likes collected
612
Location
Gloucestershire
Funster No
47,109
MH
Lunar Champ H621
Exp
15yrs
It depends on how that system interprets the information as to state of charge. Battery voltage is only an indication, the only real way to know is using a battery monitor which counts ampere hours in and out from a known point but I dont think batteries often give exactly their full capacity and it will reduce with age, number of cycles, rate of charge and just how far they have been discharged. Battery voltage is agreed to only be realistic some hours after the complete end of charge.
Empirical, I think is the word- does that mean it all depends on everything?
Mike S
 

pappajohn

LIFE MEMBER
Joined
Aug 26, 2007
Posts
43,872
Likes collected
53,745
Location
Dark side of the moon
Funster No
172
Exp
Since 2005
Battery voltage is agreed to only be realistic some hours after the complete end of charge
That's why I asked if it was still on the charger.
If the voltage was in the mid 14v's it COULD be showing a lower amperage than if it was at a steady 12.7v.... Or the batteries could simply be losing capacity.
 
Joined
Apr 27, 2016
Posts
7,474
Likes collected
8,942
Location
Manchester
Funster No
42,762
MH
A class Hymer
Exp
Since the 80s
The thing is if I set them to 220 (They are 110 each) then it shows max 100% at 176amps
Your battery capacity is 2 x 110 = 220 amp-hours. To stop you completely discharging the battery, the panel displays the capacity as 80% of that.

80% of 220 is 176. Think of it as the 'usable capacity'.

In percentage terms, when the display goes from 100% down to 0%, the battery in reality will discharge from 100% to 20%. It's like a built-in safety factor.

Of course many people reckon you shouldn't discharge a battery below 50%, which would show as 37.5% on the display panel.

50% of 220Ah is 110Ah. The displayed 0% limit is actually 220 - 176 = 44Ah, ie 20% of 220Ah.

The 110Ah level is displayed as (110-44)/176 x 100 = 37.5%

Hope this helps more than it confuses.

The panel works out the state of charge by counting the amp-hours into and out of the battery. It has a shunt resistor in the circuit to measure the amps accurately. Utilising the built-in clock, this method is more accurate than measuring the battery voltage. It is reliable even when the battery is is discharging and charging, in contrast to the voltage method which is only accurate when the battery is resting (ie not charging or discharging)
 
OP
OP
15Degrees

15Degrees

Free Member
Joined
Dec 15, 2018
Posts
32
Likes collected
8
Location
Corby
Funster No
57,595
MH
Burstner Argos 747-2
Exp
I'm a Newbie
Your battery capacity is 2 x 110 = 220 amp-hours. To stop you completely discharging the battery, the panel displays the capacity as 80% of that.

80% of 220 is 176. Think of it as the 'usable capacity'.

In percentage terms, when the display goes from 100% down to 0%, the battery in reality will discharge from 100% to 20%. It's like a built-in safety factor.

Of course many people reckon you shouldn't discharge a battery below 50%, which would show as 37.5% on the display panel.

50% of 220Ah is 110Ah. The displayed 0% limit is actually 220 - 176 = 44Ah, ie 20% of 220Ah.

The 110Ah level is displayed as (110-44)/176 x 100 = 37.5%

Hope this helps more than it confuses.

The panel works out the state of charge by counting the amp-hours into and out of the battery. It has a shunt resistor in the circuit to measure the amps accurately. Utilising the built-in clock, this method is more accurate than measuring the battery voltage. It is reliable even when the battery is is discharging and charging, in contrast to the voltage method which is only accurate when the battery is resting (ie not charging or discharging)


That actually makes sense. So essentially I SHOULD set them to the 220 then in the panel and ACCEPT that at 100% it is showing 176AH

Cheers..
 

two

Joined
Aug 4, 2011
Posts
4,914
Likes collected
4,590
Location
West Midlands
Funster No
17,624
MH
A-Class Fiat
I'm not sure what your panel is measuring. Are there no instructions?
In simple terms, If you enter the capacity as 220Ah, stop discharging/using them when it gets to 50%. If you say it's 110Ah, stop at 0%.
I'm assuming that this is an Amp-hour counter: A device that's counting the current flowing into or out of your battery bank over time.
Maybe you had already used some power before looking? Otherwise (are they Gel?) the monitor may be trying to stop you from depleting them too much (and is allowing you to use 80%). It may consider that Gel are able to go as low as 20%, but I'd try to stay well above that.
It's better to understate the capacity of your bank because it will deteriorate over time, anyway. When it says 50%, it means you have discharged 110Ah (from two 110Ah batteries). As their capacity drops, the monitor will still say 50% after 110Ah has been drawn because that's the way it works. It assumes how much is left from the capacity you enter.
Sorry if that's not clear. It's the best I can do at the moment (too much Christmas spirit).

Subscribers  do not see these advertisements

 

Join us or log in to post a reply.

To join in you must be a member of MotorhomeFun

Join MotorhomeFun

Join us, it quick and easy!

Log in

Already a member? Log in here.

Latest journal entries

Back
Top