Battery Monitoring -- How I Done It --

[TallPaul_S]

Yeah that looks perfectly fine. I'm guessing some of those lower spikes are the solar topping up the battery?

 

[TheBops]

Yep, a mix of solar top ups, short journeys and longer ones. Nice to have the monitor on for any future reference though if it starts to muck me about

 

[Dellmassive]

Yep, a mix of solar top ups, short journeys and longer ones. Nice to have the monitor on for any future reference though if it starts to muck me about

Looking good to me, voltage is staying well above 12.0v

 

[Dave512]

Looking for some advice. Recently posted about having a Lion Battery for the leisure set up (previous owner). Haven't been driving the van much for various reasons (broken leg). The voltage display does show the battery reaching 14V+ but after a few hours with nothing running the reading is showing 12-12.1V

Does this mean the battery is on the way out as I've seen the battery % chart against voltage.

Curious as to whether it's better changing now and upgrading the battery and split charger as we have a trip for the NC500 booked for the middle of May.

Any help is appreciated.

 

[Dellmassive]

The battery resting at 12.1 is fairly normal.

 

[Dave512]

Thanks @Dellmassive it's probably been like that for a while and only cause I've had the van back I've been paranoid lol

 

[redowlin]

I'm just about to embark on a small upgrade to my van and it'll be my first foray into electrics so looking for some advice. It's a van we bought already converted so making any significant changes i=would be difficult, so I want to do as much under the drivers seat as possible. Current set up is a 100Ah SLA under the drivers seat, with a 16mm2 cable (which heads off to a PMS3 at the back of the van I assume) and a smaller 4/6mm2 cable (which I think is the fridge) as the only connections to the battery +/-.

I'm adding a portable solar panel with a Victron 75/15 MPPT which I'm fairly happy with the connections for - but I'm considering installing a SmartShunt at the same time to monitor the battery state. To do this I think I'll need 3 x ring terminals on the System - side of the shunt (fridge, MPPT, battery/PMS cable). Will this fit? I expect the answer will be 'fit a busbar' but if that's not necessary I'd rather reduce the complication?

@Dellmassive your "how I done it threads" have been a veritable mine of information so far so thanks for that!

 

[TallPaul_S]

I'm just about to embark on a small upgrade to my van and it'll be my first foray into electrics so looking for some advice. It's a van we bought already converted so making any significant changes i=would be difficult, so I want to do as much under the drivers seat as possible. Current set up is a 100Ah SLA under the drivers seat, with a 16mm2 cable (which heads off to a PMS3 at the back of the van I assume) and a smaller 4/6mm2 cable (which I think is the fridge) as the only connections to the battery +/-.

I'm adding a portable solar panel with a Victron 75/15 MPPT which I'm fairly happy with the connections for - but I'm considering installing a SmartShunt at the same time to monitor the battery state. To do this I think I'll need 3 x ring terminals on the System - side of the shunt (fridge, MPPT, battery/PMS cable). Will this fit? I expect the answer will be 'fit a busbar' but if that's not necessary I'd rather reduce the complication?

@Dellmassive your "how I done it threads" have been a veritable mine of information so far so thanks for that!

Do the negatives from the devices go straight to the battery negative currently? And is there a connection from battery negative to chassis ground?


You can either connect the negatives directly to the M10 shunt system terminal, or (if the system terminal on the shunt connects to chassis ground) you can connect the device negatives to a chassis ground. That would mean one connection to the shunt then the device negatives all connections to one or more chassis ground bolts.

 

[redowlin]

Do the negatives from the devices go straight to the battery negative currently?

They do. Two devices currently - chunky 16mm2 cable which I assume goes to the PMS3 (or it could be from the split charge?) and another smaller cable which I assume is the direct connection for the fridge.

And is there a connection from battery negative to chassis ground?

Not sure - there is nothing visible - the cables disappear under the lining back towards the fridge / PMS 3 (or split charge?) at the back (I assume). I have an under-bonnet EHU as well which I also assume goes via the PMS3 - I'm currently ignoring the inefficacy of the charger on this for now.

You can either connect the negatives directly to the M10 shunt system terminal

This is the most appealing for simplicity / minimum change sake - if 3 x ring terminals will fit.

 

[roadtripper]

To do this I think I'll need 3 x ring terminals on the System - side of the shunt (fridge, MPPT, battery/PMS cable). Will this fit? I expect the answer will be 'fit a busbar' but if that's not necessary I'd rather reduce the complication?

If you're in that middle ground between having a bit too much for one terminal but not sure you need a bus bar than these 3 terminal battery clamps might offer a solution - there are matching covers as well:

Positive Battery Terminal Clamp - 3 Stud Connection

Battery terminal clamp for positive post with 3 stud connection points (2x M6, 1x M8) and nyloc nuts. Ideal for multiple auxiliary connections.

www.12voltplanet.co.uk

 

[redowling]

If you're in that middle ground between having a bit too much for one terminal but not sure you need a bus bar than these 3 terminal battery clamps might offer a solution - there are matching covers as well:

Positive Battery Terminal Clamp - 3 Stud Connection

Battery terminal clamp for positive post with 3 stud connection points (2x M6, 1x M8) and nyloc nuts. Ideal for multiple auxiliary connections.

www.12voltplanet.co.uk

Yes, I have one of those in my shopping basket for the +ve side. However as I understand it I only need one cable from the battery -ve to the battery -ve on the shunt; everything else (fridge, MPPT and what was the battery cable connection) has to go onto the system -ve terminal on the shunt. That's why I want to know if 3 ring terminals will fit on the shunt and still be able to do the bolt up.

 

[roadtripper]

That's why I want to know if 3 ring terminals will fit on the shunt and still be able to do the bolt up.

Gotcha - the challenge here is not the ring terminals as such but the diameter of the wire on them. You'll have to splay the terminals to make them fit, you must not just bolt down on them and bend the rings as the cables collide otherwise you'll likely get a bad connection on the ring or a damaged crimp area. Generally you need about 45 degrees between each cable so you'd likely be fine with a large cable and one small, but you might be on the limit with one large and 2 small.

A couple of thoughts:

These power distribution blocks make a neat bus bar/fuse solution that may let you tidy things up elsewhere and serve as a bus bar:

Mega & Midi Fuse Power Distribution Box

Compact power distribution & fuse box that distributes power theough a single mega link fuse into 4 midi or strip link fuses.

www.12voltplanet.co.uk

This junction box might let you consolidate your lower current feeds into a single feed to the shunt so you only have 2 on it:

Power Jointing Box 120A - 3 Way

300A, 3-way jointing box for connecting battery cables. Glass-filled nylon material with a hinged lid, M8 connection studs, nyloc nuts & 6mm mounting hole.

www.12voltplanet.co.uk

You might also be able to consolidate the lower current feeds using a power post rather than a full bus bar. I'm less of a fan of these on the +ve side as I think there is an increased risk of shorting, but that's a more acceptable risk where for commoning grounds, just consider how you might cover it in case you let a positive cable go when doing maintenance or trying to change a fuse in the dark.

Power Posts & Bulkhead Feed-Through Connectors | 12 Volt Planet

Power posts & bulkhead feed-through connectors for power distrbution in vehicles and boats. Marine grade fixing for corrosion resistance.

www.12voltplanet.co.uk

 

[redowling]

Not sure - there is nothing visible

@TallPaul_S Had a proper look at this today having now got all the bits I think I need. Battery negative does indeed go to a chassis ground (on the seat base). So I assume it's just a case of connecting that ground onto the system side of the shunt along with the other device negatives?

 

[TallPaul_S]

@TallPaul_S Had a proper look at this today having now got all the bits I think I need. Battery negative does indeed go to a chassis ground (on the seat base). So I assume it's just a case of connecting that ground onto the system side of the shunt along with the other device negatives?

Yep, you can connect all your negatives to either the shunt system terminal or the chassis ground that it connects to - or any chassis ground in fact

 

[lummy]

I don’t use my van from week to week so I have put a BM2 on both the starter and leisure batteries. I wanted to monitor the leisure battery when camping and starter battery when parked up so I can better judge when I need to take it for a run.

When the van is running, both batteries are charging well and within normal limits. What surprises me is the voltage and % charge readings on the starter battery when the van is parked up for a few days. After a couple of days I get low batt warnings and when cranking I also always get a low cranking warning.

The state of charge readings and inbuilt app warnings don’t seem to correlate to the tables earlier in this thread. Is this because the BM2 algorithms do not take into account the T6 smart alternator setup?

I am coming to the conclusion that I have to largely ignore the % values and associated warnings and that I should focus on the voltage.

So far I have never had an issue starting the van.

After a long run the starter steadily drops from circa 12.5v to 12.3v over a few days. The monitor considers this as Low.

The cranking voltage is always low at 9.32v.

On the starter battery what voltage can I safely let it fall to? I assume anything above 12.1 ish is ok.

What readings do other get for both cranking and after the van has been parked up for a few days?

I have also discovered that you can change the app alarm parameters. What setting have you got?

hello Dellmassive . i know this is a old post but is one of the few that seems relevant to my situation , i have a victron shunt fitted and as you say during a long run after first charging starter at 14.4-14.6v drops to 12.2-12.4v . my van is set up as a camper and not used very much this time of the year ,the voltage seem to drop about 0.1v per day when not in use so at what point do you think i should run out with the charger been leaving it till about 11.5v, van parked on road so a bit inconvenient running charger down path once a week do you think a small window mounted solar panel a option , was thinking of removing battery into house but after reading about it think this might bring up more problems than it solves . any comments welcome .

 

[Dellmassive]

hello Dellmassive . i know this is a old post but is one of the few that seems relevant to my situation , i have a victron shunt fitted and as you say during a long run after first charging starter at 14.4-14.6v drops to 12.2-12.4v . my van is set up as a camper and not used very much this time of the year ,the voltage seem to drop about 0.1v per day when not in use so at what point do you think i should run out with the charger been leaving it till about 11.5v, van parked on road so a bit inconvenient running charger down path once a week do you think a small window mounted solar panel a option , was thinking of removing battery into house but after reading about it think this might bring up more problems than it solves . any comments welcome .

You should be looking to keep the starter battery voltage above 12.0v.

Bellow that it will degrade quickly.

Solar is very poor this time of year.

Take a look at this thread.....

[Guide] Battery Maintainer (for Starter battery) -- How I Done It --

[Guide] Battery Maintainer (for Starter battery) -- How I Done It -- Right so its that time of year again . . . . . . . . Winter & (Lockdown 2020) The van might be layed up not being used, which will lead to a flat battery in around 3 weeks. The cold weather doesn't help the battery's...

www.t6forum.com

.

 

[TallPaul_S]

Solar is very poor this time of year.

Second this, I doubt a small portable panel would be able to keep a starter battery topped up over winter, unless you angled it facing the sun all day long.

I've got a 300w panel on my van and I struggle to get above 60Wh a day at the moment. 60Wh is about 5Ah. That's enough to cover a 0.2a constant draw.

 

[CAB]

hello Dellmassive . i know this is a old post but is one of the few that seems relevant to my situation , i have a victron shunt fitted and as you say during a long run after first charging starter at 14.4-14.6v drops to 12.2-12.4v . my van is set up as a camper and not used very much this time of the year ,the voltage seem to drop about 0.1v per day when not in use so at what point do you think i should run out with the charger been leaving it till about 11.5v, van parked on road so a bit inconvenient running charger down path once a week do you think a small window mounted solar panel a option , was thinking of removing battery into house but after reading about it think this might bring up more problems than it solves . any comments welcome .

A 10w panel does nothing from October onwards.

I imagine at least 50w would be required.

 

[CAB]

hello Dellmassive . i know this is a old post but is one of the few that seems relevant to my situation , i have a victron shunt fitted and as you say during a long run after first charging starter at 14.4-14.6v drops to 12.2-12.4v . my van is set up as a camper and not used very much this time of the year ,the voltage seem to drop about 0.1v per day when not in use so at what point do you think i should run out with the charger been leaving it till about 11.5v, van parked on road so a bit inconvenient running charger down path once a week do you think a small window mounted solar panel a option , was thinking of removing battery into house but after reading about it think this might bring up more problems than it solves . any comments welcome .

Other alternatives:

Leisure battery + battery maintainer - what do you have? If Lithium, could you install an Ablemail?

Powerpack + 240v charger - do you have access to a powerpack with 240v output - stick it in once a week with a CTEK charger plugged in?

 

[lummy]

i can see what people are saying on solar panels output this time of year being pitiful at best even on a large setup , powerpack with a 240 charger sounds interesting but how long a affordable powerpack with a 240v charger pluged in would last ?.
will have a read of Dellmassive post on "[Guide] Battery Maintainer (for Starter battery) -- How I Done It --" and try and educate myself .