Checking battery level (1 Viewer)

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Mar 21, 2022
429
262
Funster No
87,579
MH
autosleeper
Hi all
If you don't trust the onboard control panel readings for the state of your batteries, then whats the best and most accurate way of telling how much is left in your battery?
 
Apr 27, 2016
7,383
8,786
Manchester
Funster No
42,762
MH
A class Hymer
Exp
Since the 80s
A quick simple,cheep way of knowing.
As the saying goes, pick any two. :giggle:

The question is, I think, does the voltmeter on the Sargent unit give you the actual terminal voltage of the battery? If it does, then you can switch off any loads, and if there's no solar charging (at night for example) then the voltage chart will give you an approximate state of charge.

If the Sargent meter is not accurate, then any of the voltmeters suggested can be used instead, in the same situation.

For a more accurate state of charge reading, valid even when charging or under load, a shunt monitor is best, but is more trouble to install.
 
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Dec 24, 2014
9,871
51,844
Hurstpierpoint. Mid Sussex.
Funster No
34,553
MH
Compass Navigator
Exp
Ever since lighting was by Calor gas.
Wow heads mushed again.
All I want to know really is when I've been off grid when batteries need charging.
A quick simple,cheep way of knowing.
I don't have much confidence in the on board sargent ec200 control panels read outs
A very simple answer and rough guide is to check their voltage after being off-load for say 30 mins. Best done with a test meter (available for around a tenner) direct to the batteries' terminals unless you have verified the accuracy of the readings on the Anxiety Panel.
Recharge at any time but certainly when down to 11.6V.
 
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Dec 2, 2019
3,875
8,558
Amersham
Funster No
67,145
MH
van conversion
Exp
Since 2019
I may add, for those that don’t know what a shunt(resistor), does; the clue it’s in the name, shunting all the current trough a intended path. Because, the shunt has a known fixed resistance value, the microchip, applies ohms low and other calculations, upon the current passing the resistor, a minimal voltage drop will occur. Based on that value the chip calculates the amps flow, voltage drop taking peukert into account, and battery capacity entered. It does multiple complex calcs, given you a pretty accurate data of current flow for charge, discharge and state of charge.
A multimeter, can only read voltage at that instance, nothing more.
 
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Feb 9, 2008
8,968
18,777
Corby, Northants
Funster No
1,455
MH
Coach Built
Exp
Since 2007
Wow heads mushed again.
All I want to know really is when I've been off grid when batteries need charging.
A quick simple,cheep way of knowing.
I don't have much confidence in the on board sargent ec200 control panels read outs
Your not alone! It's a minefield and not helped by the different views posted by members. However, a cheap way forward for you is to get a £10.0 volt meter and then you can measure battery voltage directly from your battery and compare with control panel readouts.

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Feb 22, 2016
3,805
12,188
York
Funster No
41,744
MH
Bailey 620 Approach
Exp
Since 2015
I use one of those and also charge my vehicle and hab batteries by plugging the charger in to the same permanently live cig lighter socket which saves having to access the batteries.
(I can select whether to supply the cig lighter from the vehicle or the hab battery).
I’ve got one of these but don’t find it as accurate as putting the digital meter probes directly on the battery or the test points on my Peugeot Boxer based Bailey. It’s a ‘quick and easy’ check so it is useful.
 
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