Leisure battery monitor

[nabsim]

I find it hard to understand how some people manage ok in winter with solar my batterys go one way down

Different locations, different weather, different usage requirements. Easier to just accept there are differences

 

[Garyb88]

I was just about to make a post to say the Cables on these Aili Meters are rediculously short (500mm compared to the 10M or Longer ones on the Victron BMVs).
Not found a source for the plug and socket connectors, so what I usually do is modifiy the original one to insert an extension length as the extension cable you can buy is way too pricey for what it is.

Old thread. But I was just wondering if you know what would be the max length I could extend the unit too? Thanks if you see this.

 

[wildebus]

Old thread. But I was just wondering if you know what would be the max length I could extend the unit too? Thanks if you see this.

I don't know, but I can't see any reason why it can't be as long as you need within the confines of a motorhome.

 

[CriftinsCampers]

The two wires that matter are those measuring the comparative miniscule volt drop across the shunt.
There’s very little current flow in those two wires to the monitor, and it’s current that causes volt drop down a given length and thickness of wire.

That being said there’s very little comparative difference in voltage when measuring a relatively low current across the shunt so just be aware there’s always some volt drop over any given length of wire, however hopefully in this case it’s will be negligible.

The cable seems to be the same screened stuff used for usb leads, I chopped an old usb cable up to extend mine by approx 2m.

The two wires I used from the shunt were the two that form the twisted pair in the cable green and white iirc and over a longer distance this may be beneficial to reduce error due to induction especially from any adjacent cables

You can buy usb cables up to 5m long if you needed to go longer than that then use something of a continuous length such as a bit of Cat5 as the fewer joints the better.

 

[mikewroe]

Hoping to resurrect this very informative posting.
I would like to monitor my own batteries using either the Victron Bluetooth shunt or the Aili wired display version as recommended by Widebus.
Before I make the final decision, I just wondered if having two batteries in parallel could mess with the readings? I assume that the current will always flow from the battery with the greatest voltage?
Would it be more accurate to have a monitor/shunt on each of the batteries?

 

[wildebus]

Hoping to resurrect this very informative posting.
I would like to monitor my own batteries using either the Victron Bluetooth shunt or the Aili wired display version as recommended by Wildebus.
Before I make the final decision, I just wondered if having two batteries in parallel could mess with the readings? I assume that the current will always flow from the battery with the greatest voltage?
Would it be more accurate to have a monitor/shunt on each of the batteries?

if you have the Batteries as a single bank, you have the two -ves together and the two +ves together. Then if you connect the Shunt -BAT to one of the -ves (and it is the ONLY thing connected to the -ve apart from the other battery of course), then it is monitoring both batteries as a combined bank. And you set the capacity in the monitor to the total of the two batteries.

You could have a monitor on each battery if you wanted. not a lot of point unless you are curious about how each is working. Bear in mind these are Monitors only and have no effect on how the batteries are actually used.
(FWIW, I have a Victron BMV on one bank, another on the other bank and a third on the overall bank as a whole, but I don't have the typical setup )

Also .... at the original date of this thread, the Victron Monitors were a LOT more expensive. Right now they are a lot cheaper and I would recommend Victron rather than the Alii Monitor now the price difference is a lot closer.

 

[mikewroe]

if you have the Batteries as a single bank, you have the two -ves together and the two +ves together. Then if you connect the Shunt -BAT to one of the -ves (and it is the ONLY thing connected to the -ve apart from the other battery of course), then it is monitoring both batteries as a combined bank. And you set the capacity in the monitor to the total of the two batteries.

You could have a monitor on each battery if you wanted. not a lot of point unless you are curious about how each is working. Bear in mind these are Monitors only and have no effect on how the batteries are actually used.
(FWIW, I have a Victron BMV on one bank, another on the other bank and a third on the overall bank as a whole, but I don't have the typical setup )

Also .... at the original date of this thread, the Victron Monitors were a LOT more expensive. Right now they are a lot cheaper and I would recommend Victron rather than the Alii Monitor now the price difference is a lot closer.

Thanks for confirming that David.
The idea of a simple connection and no wiring as its Bluetooth gets my vote.
Are they still available through yourself?

 

[wildebus]

Thanks for confirming that David.
The idea of a simple connection and no wiring as its Bluetooth gets my vote.
Are they still available through yourself?

The Smartshunt is probably the most popular Battery Monitor as it is so simple to install

I can supply these (link), but so of course can plenty of other places including the autolink above to BMS Technologies (in case anyone thinks was recommending for non-genuine reasons).

 

[Landyseverywhere]

I find it hard to understand how some people manage ok in winter with solar my batterys go one way down

I have 400w on the roof and Renogy b2b mppt controller( keeps SB topped up )
every time I've looked LB &SB fully charged (220 Flooded lb) according to app circa 30/34 ah per Month Is it a case of the sun shines on the righteous ?(or just Lincolnshire)

 

[wildebus]

I have 400w on the roof and Renogy b2b mppt controller( keeps SB topped up )
every time I've looked LB &SB fully charged (220 Flooded lb) according to app circa 30/34 ah per Month Is it a case of the sun shines on the righteous ?(or just Lincolnshire)

34Ah per Month? You are generating in one month 1/6th of your battery capacity. if that is sufficient, you could go without any solar for 3 months and still not be down to 50% discharged.
34Ah is a tiny amount of power in a month - that is around 13Wh per day - you couldn't run an LED light on that for more than maybe 2-3 hours at the most.


I suspect the 30/34Ah a month might be a typo? (my fridge uses more than that every day ).
Just checked my numbers and last month was a touch more than sunny Lincolnshire at 1430Ah (or 17.27kWh). Sadly still not enough to run the fridge, but the weather has been pants everywhere

 

[Landyseverywhere]

34Ah per Month? You are generating in one month 1/6th of your battery capacity. if that is sufficient, you could go without any solar for 3 months and still not be down to 50% discharged.
34Ah is a tiny amount of power in a month - that is around 13Wh per day - you couldn't run an LED light on that for more than maybe 2-3 hours at the most.


I suspect the 30/34Ah a month might be a typo? (my fridge uses more than that every day ).
Just checked my numbers and last month was a touch more than sunny Lincolnshire at 1430Ah (or 17.27kWh). Sadly still not enough to run the fridge, but the weather has been pants everywhere

No not a typo.did actually get as high as 44ah in December,guess I must have switched something on briefly,so. IF the app is accurate just over 1 ah per day,when nothing is on leisure side and engine side is is on life support and 3 batteries self discharge.
Would like to double check with meter on starter battery only at some point as this seems on the low side (but shows fairly consistent month on month) ,even if 20% inaccurate still wouldn't make much difference . What would you expect ? Bearing in mind lb isolator is off.

 

[wildebus]

No not a typo.did actually get as high as 44ah in December,guess I must have switched something on briefly,so. IF the app is accurate just over 1 ah per day,when nothing is on leisure side and engine side is is on life support and 3 batteries self discharge.
Would like to double check with meter on starter battery only at some point as this seems on the low side (but shows fairly consistent month on month) ,even if 20% inaccurate still wouldn't make much difference . What would you expect ? Bearing in mind lb isolator is off.

I don't know if you are mixing up Ah - Amp Hours - with something else, but seriously 1Ah a day is a tiny tiny amount - 12 Wh (Watt-Hours).
Turn on an old fashioned electric light and you will use 12Wh in 10 minutes.
I would expect the residual drain on the starter battery to easily exceed 1Ah/Day.


When you quoted a post from Molly which said "I find it hard to understand how some people manage ok in winter with solar my batterys go one way - down" and described your experience, I had kind of assumed you were referring to a motorhome that was actually in use, and not one that was in storage with the Leisure Batteries isolated and not in use

I guess I must be missing some kind of irony or sarcasm?

 

[Landyseverywhere]

I don't know if you are mixing up Ah - Amp Hours - with something else, but seriously 1Ah a day is a tiny tiny amount - 12 Wh (Watt-Hours).
Turn on an old fashioned electric light and you will use 12Wh in 10 minutes.
I would expect the residual drain on the starter battery to easily exceed 1Ah/Day.


When you quoted a post from Molly which said "I find it hard to understand how some people manage ok in winter with solar my batterys go one way - down" and described your experience, I had kind of assumed you were referring to a motorhome that was actually in use, and not one that was in storage with the Leisure Batteries isolated and not in use

I guess I must be missing some kind of irony or sarcasm?

No irony or sarcasm intended,having read many posts about SB going flat in storage ,I obviously wrongly assumed this was what was being referred to.
Also just thought the numbers I'm seeing. could they be what has gone into the batteries and be what is being replaced during hours of darkness,whilst drain during daylight is not captured ??? as it never enters the battery,
sounds unlikely to me but would it be possible?

 

[Landyseverywhere]

No irony or sarcasm intended,having read many posts about SB going flat in storage ,I obviously wrongly assumed this was what was being referred to.
Also just thought the numbers I'm seeing. could they be what has gone into the batteries and be what is being replaced during hours of darkness,whilst drain during daylight is not captured ??? as it never enters the battery,
sounds unlikely to me but would it be possible?

Sorry should have been replenishing what was used during hours of darkness

 

[wildebus]

Sorry should have been replenishing what was used during hours of darkness

The difference in readings between a full day and when dark is a good point. It depends how the device you are reading the info from is using the data and the difference could quite literally be night and day

So taking your setup where the only input into the battery is from Solar ...
If the readings are from a Battery Monitor, the Amp-Hours could be the net difference between Power Used and Power Harvested, so the actual Solar harvested is greater than the value as power loads around the motorhome could be effectively fed directly from the solar (such as a Starter Battery trickle charger).
If the readings are from a Monitor reading the Solar Controller, that would be the actual amount of Solar harvested.
May or may not be of interest, but these two screenshots I just did may illustrate this?
This is the Battery Monitor in my Motorhome:
Right now is getting 3.3A fed into the Battery from the Solar


And at the same time, this is the Solar 'Monitor' for the Solar Roof Panels:
It is feeding 7.40A into the system from the panels (about 100W coming in from the 450W array)

Which means 4.10A (7.40 - 3.30) is being used by the Motorhome and the battery is not providing any power. So it does depend very much on what point you are measuring to know what is what.
In your case, the solar is keeping the batteries fully replenished I would say as the power coming in from a decent sized array is low and you have a very low demand right now..
In my case, the solar would be providing all that it is capable of (which is not a lot in the current weather situation) to try and raise that -363.9Ah back to 0Ah (Full).
The difference between our setups would be you have turned everything off and isolated the batteries, etc so have no notable power demands whereas I have my Electric Fridge/Freezer running as well as having random things like internet routers and USB sockets powered.

 

[Landyseverywhere]

Thanks for your time and information ,so the latent draw to keep it's heart beating will be very roughly(dependant on hrs of light) double the amount recorded.I will at some point put a meter between the SB and van just to see what actual power life support takes,but being a boxer and having a secured tailored Matt over cab floor a pita .
Thanks again for the information

 

[Landyseverywhere]

Strangely I'm getting 7.4 a into battery having drained it by 10% with isolator off (400w panels) so very little different to yours,must be a bit brighter here but negligible