Battery Monitoring -- How I Done It --
Part #1
Battery monitoring is a very important part of your 12v system . . . . whether its just the vans starter battery or your leisure setup keeping an eye on the power in your battery bank will keep you from breaking down and make sure your weekends are not cut short from lack of power.
Battery monitoring is even more important with Lithium Lifepo4 batteries as the voltage stays fairly constant for 90% of the capacity.
first off lets look at a few basic 12v meters.
here a great little unit that I've been using for ages....
you can plug it into your 12v socket and it will you you a basic voltage reading. . . .
Dual USB Car Charger - Jebsens Top Rated Car Charger with Two USB Ports, 4.8A/24W,
.
.
But what do those numbers mean?
well, when the engine is not running it will show you the Voltage of the battery . . . from this we can get a rough idea of SOC "state of charge" or the DOD depth of discharge.
this chart is an idea for a SLA "Sealed Lead Acid" battery.
we can see that with a voltage of 12.4v the battery could be 80%.
++++++++++++++
here is the same chart for an AGM battery, the type of battery on a T6 and stop/start car
+++++++++++++++
anf just for reference, here is a Lifepo4 leisure battery chart.
++++++++++++++++
One thing to note is that when you are drawing a load from the battery these numbers and readings will go a bit squiffy, this is due to something called volt drop. . . . its similar to water pressure in a pipe dropping when you open a tap. . . . . . . so these numbers are best observed when all your kit is switched off . . . .
here are another couple of examples of volt meters that can be hard wired . . . though it may be best to wire them through a switch so that they are not on 24/7
#1
LED small round Volt Gauge - XCSOURCE Car Motorcycle Waterproof Blue LED Digital Panel Display Voltmeter Voltage Volt Meter Gauge Black DC 12V MA1028: Amazon.co.uk: Electronics
#2
LED Slim Volt Meter - EEEKit Car Motorcycle Digital Voltmeter, White LED: Amazon.co.uk: Electronics
.
So you get the idea of the voltage means at rest . . . but what about charging?
well you can you the voltmeter to monitor the charge voltage from your alternator, EHU, solar or DC-DC charger .. . . as a rough guide we have this for the smart chargers:
********************************************************************
What are the smart charger stages?
Adaptive three step charging, are configured for a three-step (or more) charging process: Bulk – Absorption – Float. (these values depend on the battery type, temperature, current - so are variable)
Bulk (14.6v - 15.3v) During this stage the controller delivers as much charge current as possible to rapidly recharge the batteries.
Absorption (14.6v - 15.3v) When the battery voltage reaches the absorption voltage setting, the controller switches to constant voltage mode. For lead acid batteries it is important that during shallow discharges the absorption time is kept short in order to prevent overcharging of the battery.
Float (13.2v - 13.6v) During this stage, float voltage is applied to the battery to maintain it in a fully charged state. When the battery voltage drops substantially below this level, due to a high load for example, during at least 1 minute, a new charge cycle will be triggered.
*********************************************************************
Redarc BCDC1250D spec - https://www.redarc.com.au/Content/Images/uploaded/BCDC1250D Instruction Manual.pdf
REDARC BCDC1240 40A 12 V DC-DC -
REDARC 8065 40 A 12 V DC Battery Charger: Amazon.co.uk: Car & Motorbike
.
If you have both the starter and leisure battery setup them it may be worth looking at two separate 12v monitors or look at some of the available dual voltage monitors, like this :
***************************************************
Now these are all very nice, but what about bluetooth and your smartphone?
well these have been around a while now,
the first version i had was the CTEK CTX Battery Sense:
a nice small device that attaches to the battery and has a nice APP for your smartphone, when you are in range (10meters ish) it will update the phone and give you live readings of SOC and voltage/temp.
CTX BATTERY SENSE
CTEK Vehicle Battery Monitor - CTEK 40-149 Vehicle Battery Monitor: Amazon.co.uk: Car & Motorbike
************************
another option that i now favor is the Quicklynx BM2
Bm2 Battery Monitor: - QUICKLYNKS Battery Monitor BM2 Bluetooth 4.0 Device Car 12V Battery Tester Diagnostic Tool for Android iOS iPhone Digital Analyzer Battery Measurement Units: Amazon.co.uk: DIY & Tools
its a similar device, but gives more more data and a brilliant history readout so you can monitor voltage trends over night or then whole weekend . . . . similar to the CTEK but a bit better IMHO.
You can see the effects of the DC-DC charger above and its different stages and how that effects the battery voltage.
.
.
Bm2 Battery Monitor: - QUICKLYNKS Battery Monitor BM2 Bluetooth 4.0 Device Car 12V Battery Tester Diagnostic Tool for Android iOS iPhone Digital Analyzer Battery Measurement Units: Amazon.co.uk: DIY & Tools
Part#2 to follow.
******************************************
Kit List And Stuff -- How I Done It & What I Use --
******************************************
Dellmassive`s -- "how I Done It" -- Thread
******************************************
******************************************************
.
Part #1
Battery monitoring is a very important part of your 12v system . . . . whether its just the vans starter battery or your leisure setup keeping an eye on the power in your battery bank will keep you from breaking down and make sure your weekends are not cut short from lack of power.
Battery monitoring is even more important with Lithium Lifepo4 batteries as the voltage stays fairly constant for 90% of the capacity.
first off lets look at a few basic 12v meters.
here a great little unit that I've been using for ages....
you can plug it into your 12v socket and it will you you a basic voltage reading. . . .
Dual USB Car Charger - Jebsens Top Rated Car Charger with Two USB Ports, 4.8A/24W,
.
.
But what do those numbers mean?
well, when the engine is not running it will show you the Voltage of the battery . . . from this we can get a rough idea of SOC "state of charge" or the DOD depth of discharge.
this chart is an idea for a SLA "Sealed Lead Acid" battery.
we can see that with a voltage of 12.4v the battery could be 80%.
++++++++++++++
here is the same chart for an AGM battery, the type of battery on a T6 and stop/start car
+++++++++++++++
anf just for reference, here is a Lifepo4 leisure battery chart.
++++++++++++++++
One thing to note is that when you are drawing a load from the battery these numbers and readings will go a bit squiffy, this is due to something called volt drop. . . . its similar to water pressure in a pipe dropping when you open a tap. . . . . . . so these numbers are best observed when all your kit is switched off . . . .
here are another couple of examples of volt meters that can be hard wired . . . though it may be best to wire them through a switch so that they are not on 24/7
#1
LED small round Volt Gauge - XCSOURCE Car Motorcycle Waterproof Blue LED Digital Panel Display Voltmeter Voltage Volt Meter Gauge Black DC 12V MA1028: Amazon.co.uk: Electronics
#2
LED Slim Volt Meter - EEEKit Car Motorcycle Digital Voltmeter, White LED: Amazon.co.uk: Electronics
.
So you get the idea of the voltage means at rest . . . but what about charging?
well you can you the voltmeter to monitor the charge voltage from your alternator, EHU, solar or DC-DC charger .. . . as a rough guide we have this for the smart chargers:
********************************************************************
What are the smart charger stages?
Adaptive three step charging, are configured for a three-step (or more) charging process: Bulk – Absorption – Float. (these values depend on the battery type, temperature, current - so are variable)
Bulk (14.6v - 15.3v) During this stage the controller delivers as much charge current as possible to rapidly recharge the batteries.
Absorption (14.6v - 15.3v) When the battery voltage reaches the absorption voltage setting, the controller switches to constant voltage mode. For lead acid batteries it is important that during shallow discharges the absorption time is kept short in order to prevent overcharging of the battery.
Float (13.2v - 13.6v) During this stage, float voltage is applied to the battery to maintain it in a fully charged state. When the battery voltage drops substantially below this level, due to a high load for example, during at least 1 minute, a new charge cycle will be triggered.
*********************************************************************
Redarc BCDC1250D spec - https://www.redarc.com.au/Content/Images/uploaded/BCDC1250D Instruction Manual.pdf
REDARC BCDC1240 40A 12 V DC-DC -
REDARC 8065 40 A 12 V DC Battery Charger: Amazon.co.uk: Car & Motorbike
.
If you have both the starter and leisure battery setup them it may be worth looking at two separate 12v monitors or look at some of the available dual voltage monitors, like this :
***************************************************
Now these are all very nice, but what about bluetooth and your smartphone?
well these have been around a while now,
the first version i had was the CTEK CTX Battery Sense:
a nice small device that attaches to the battery and has a nice APP for your smartphone, when you are in range (10meters ish) it will update the phone and give you live readings of SOC and voltage/temp.
CTX BATTERY SENSE
CTEK Vehicle Battery Monitor - CTEK 40-149 Vehicle Battery Monitor: Amazon.co.uk: Car & Motorbike
************************
another option that i now favor is the Quicklynx BM2
Bm2 Battery Monitor: - QUICKLYNKS Battery Monitor BM2 Bluetooth 4.0 Device Car 12V Battery Tester Diagnostic Tool for Android iOS iPhone Digital Analyzer Battery Measurement Units: Amazon.co.uk: DIY & Tools
its a similar device, but gives more more data and a brilliant history readout so you can monitor voltage trends over night or then whole weekend . . . . similar to the CTEK but a bit better IMHO.
You can see the effects of the DC-DC charger above and its different stages and how that effects the battery voltage.
.
Bm2 Battery Monitor: - QUICKLYNKS Battery Monitor BM2 Bluetooth 4.0 Device Car 12V Battery Tester Diagnostic Tool for Android iOS iPhone Digital Analyzer Battery Measurement Units: Amazon.co.uk: DIY & Tools
Part#2 to follow.
******************************************
Kit List And Stuff -- How I Done It & What I Use --
******************************************
Dellmassive`s -- "how I Done It" -- Thread
******************************************
******************************************************
- Charging:
- Battery Chargers - How I Did It -
- Battery Charging - Main Battery Earth Point -
- Battery Monitoring -- How I Done It --
- [Guide] Battery Maintainer (for Starter battery) -- How I Done It --
- Which Jump Starter?
- Seat Base Electrics, EHU+Charger+solar+install - How We Done It -
.
Last edited: