12 volt control box.

[Kappy]

Currently travelling in my Sprinter van, I have a second battery set up, currently an average Lead Acid.
I have a battery box with input/output, but considering hiding battery and setting up a 12 Volt Control box like this
https://www.bcf.com.au/p/xtm-12v-contro ... 20#start=1
My question the brains truss, is it possible to construct one cheaper that buying one already to go.
I realise doing it myself it can be customised, but it will only be simple with cig and Anderson plug output etc, with input for future portable solar panel.
Also considering changing the 2nd Battery to an AGM as my fridge drains the lead acid battery to the point of low voltage issues with fridge.
Cheers

[T1 Terry]

There is no battery disconnect if the battery goes over voltage or under voltage, so the battery is just at the mercy of the user. Suggesting it is pre wired for solar is just rubbish, it is just a connection to the battery with a fuse in it.

An AGM battery is just another type of lead acid battery, if the fridge drains the battery you have, then it will drain the same capacity AGM battery.
Could you custom build the same thing cheaper ..... probably, but it would still be inadequate to what you really need.
How do you recharge the battery now if you don't have solar?

T1 Terry

[Mrcoolabah1au]

[Kappy]

There is no battery disconnect if the battery goes over voltage or under voltage, so the battery is just at the mercy of the user. Suggesting it is pre wired for solar is just rubbish, it is just a connection to the battery with a fuse in it.

An AGM battery is just another type of lead acid battery, if the fridge drains the battery you have, then it will drain the same capacity AGM battery.
Could you custom build the same thing cheaper ..... probably, but it would still be inadequate to what you really need.
How do you recharge the battery now if you don't have solar?

T1 Terry

Its charged by the Vans alternator via a dual battery switch thingy.
So maybe its not getting enough, had my multimeter on it while engine running and was getting 12.9volts on idle.

[T1 Terry]

There is no battery disconnect if the battery goes over voltage or under voltage, so the battery is just at the mercy of the user. Suggesting it is pre wired for solar is just rubbish, it is just a connection to the battery with a fuse in it.

An AGM battery is just another type of lead acid battery, if the fridge drains the battery you have, then it will drain the same capacity AGM battery.
Could you custom build the same thing cheaper ..... probably, but it would still be inadequate to what you really need.
How do you recharge the battery now if you don't have solar?

T1 Terry

Its charged by the Vans alternator via a dual battery switch thingy.
So maybe its not getting enough, had my multimeter on it while engine running and was getting 12.9volts on idle.

You need to measure the amps going through the cable to actually charge the battery and you need a DC clamp meter for that job.
12.9v won't fully charge a battery, but it would bring it up to around 70% charged given a few days, so a few hrs driving isn't going to get it recharged much at all.
I'd recommend either a Victron 30 amp DC to DC or a 40 amp Enerdrive DC to DC charger. Fit it close to the house battery and make sure the cables are at least 13.5mm sq (6 B&S) both from the start battery to the DC to DC and from there to the house battery. Set the DC to flooded cell battery type to ensure the charging voltage is high enough to get the most into the lead acid battery as it can while you are driving.

T1 Terry

[RobertNotBob]

These are well built and a bit cheaper https://www.4wdsupacentre.com.au/produc ... tml?page=2

[Kappy]

There is no battery disconnect if the battery goes over voltage or under voltage, so the battery is just at the mercy of the user. Suggesting it is pre wired for solar is just rubbish, it is just a connection to the battery with a fuse in it.

An AGM battery is just another type of lead acid battery, if the fridge drains the battery you have, then it will drain the same capacity AGM battery.
Could you custom build the same thing cheaper ..... probably, but it would still be inadequate to what you really need.
How do you recharge the battery now if you don't have solar?

T1 Terry

Its charged by the Vans alternator via a dual battery switch thingy.
So maybe its not getting enough, had my multimeter on it while engine running and was getting 12.9volts on idle.

You need to measure the amps going through the cable to actually charge the battery and you need a DC clamp meter for that job.
12.9v won't fully charge a battery, but it would bring it up to around 70% charged given a few days, so a few hrs driving isn't going to get it recharged much at all.
I'd recommend either a Victron 30 amp DC to DC or a 40 amp Enerdrive DC to DC charger. Fit it close to the house battery and make sure the cables are at least 13.5mm sq (6 B&S) both from the start battery to the DC to DC and from there to the house battery. Set the DC to flooded cell battery type to ensure the charging voltage is high enough to get the most into the lead acid battery as it can while you are driving.

T1 Terry

Bare with me, I gather by installing DC to DC would I dismiss my Dual Battery switch?

[T1 Terry]

No, you can still have the dual battery switch if the feed end goes to the start battery or alternator, the DC to DC input cable goes on the connection that did go to the house battery, it just runs through the DC to DC now to boost the voltage before it goes into the house battery

T1 Terry

[Kappy]

Thanks Terry
Cheers

[Kappy]

No, you can still have the dual battery switch if the feed end goes to the start battery or alternator, the DC to DC input cable goes on the connection that did go to the house battery, it just runs through the DC to DC now to boost the voltage before it goes into the house battery

T1 Terry

Not that happy with isolation switch, if I don't turn off I think the second starts to drain start battery, I forget to turn off and on.
With the right DC2DC charger it turns on with ignition so with ignition off, no backward drain, yes?
This looks like an investment with the future in mind.
https://www.ebay.com.au/itm/13307995904 ... Track=true
Cheers