Alternator output

[Rioja John]

Your attachment doesn’t work Wayne.

 

[Drive Wayne]

Your attachment doesn’t work Wayne.

Try again, I posted the wrong Pic!

 

[Drive Wayne]

Try again, I posted the wrong Pic!

Surely it's the 63% that matters, not the voltage? How many Ah are your batteries holding? Not the volts!

 

[Rioja John]

According to the booklet that came with the batteries at 13.1 volts they’re down to 20% capacity.

 

[Rioja John]

I’ve sent you a dm Wayne.

 

[Salty Spuds]

According to the booklet that came with the batteries at 13.1 volts they’re down to 20% capacity.

Voltage isn’t an indicator of SOC when it comes to lithium. You either need a smart BMS or a shunt.

 

[Rioja John]

This is what came with my batteries and I’m going by. So according to this I’m down to about 25% so the Victron should charge more than it does.

 

[Rioja John]

Victron shunt ordered.

 

[Drive Wayne]

Victron shunt ordered.

£80 well spent John, you'll thank us, in due course!

 

[Simon Audi]

Hi - Totally new to this

I have ordered a Fogstar Drift 105A Lithium, A Victron 12/375 Inverter, Victron 12 - 12 -30A DC DC Charger and Victron IP65 12/25A Charger for my Kombi.

Obviously cables etc for connection.

NO Shunts...... Do I need shunts? or Similar? The battery has Blue tooth as does the charger?

THANKS

 

[Salty Spuds]

Hi - Totally new to this

I have ordered a Fogstar Drift 105A Lithium, A Victron 12/375 Inverter, Victron 12 - 12 -30A DC DC Charger and Victron IP65 12/25A Charger for my Kombi.

Obviously cables etc for connection.

NO Shunts...... Do I need shunts? or Similar? The battery has Blue tooth as does the charger?

THANKS

It all depends on how clever the battery is. Some batteries have all the magicary built in, so they monitor their own State Of Charge (SOC) and you read this via an app & Bluetooth. Other batteries are dumb & need managing externally via a 3rd party device, e.g. a shunt. So the answer is… it depends.
I’m not familiar with the Fogstar batteries so can’t comment on your specific case.

 

[Rioja John]

Think I’m a thick shunt.

 

[Salty Spuds]

Think I’m a thick shunt.

Oh don’t be hard on yourself, we don’t think you’re…..thick

 

[roadtripper]

Hi - Totally new to this

I have ordered a Fogstar Drift 105A Lithium, A Victron 12/375 Inverter, Victron 12 - 12 -30A DC DC Charger and Victron IP65 12/25A Charger for my Kombi.

Obviously cables etc for connection.

NO Shunts...... Do I need shunts? or Similar? The battery has Blue tooth as does the charger?

THANKS

Unless you are really going to stretch the capacity with sustained off grid use or you just like lots of data then probably not.

That's a good set of kit, though I'd go for the smaller and cooler running Orion XS DC-DC and downrate in software.

If you find you do need one they are reasonably simple to retrofit as you install them in the battery ground side same as the shunt on the main van battery. If you want to future proof then maybe mock one up in cardboard and leave space for it when planning your install.

 

[Simon Audi]

Thanks

Its to run a dehumidifer - so running around 15A for 2 to 3 hours a day.... 2 if its dry - 3 if its wet (based on this weeks tests) through the inverter - Dogs do a lot of heavy breathing...

I was hoping that with the DC DC I can live 2 to 3 days before having to top up the charge - That's why I went the 30A - as it will at best be running daily for 20 minutes off the Alternator...(To and From Dog Walk) then a longer run at the weekends.

THANKS

 

[Salty Spuds]

Thanks

Its to run a dehumidifer - so running around 15A for 2 to 3 hours a day.... 2 if its dry - 3 if its wet (based on this weeks tests) through the inverter - Dogs do a lot of heavy breathing...

I was hoping that with the DC DC I can live 2 to 3 days before having to top up the charge - That's why I went the 30A - as it will at best be running daily for 20 minutes off the Alternator...(To and From Dog Walk) then a longer run at the weekends.

THANKS

What dehumidifier are you going to be running? Your inverter is only 375W, which may on paper be enough to run your dehumidifier. But a Dhr is basically a fridge running with the door open, & the start up current could be 4-5 times the running current.

 

[Simon Audi]

Its a Meaco - Arete Two - 12L Per Day.

Its a 155W Power Consumption - So Theoretically less than half the 375 Watt Inverter.

So hopefully will all be OK...

 

[roadtripper]

That's a compressor based dehumidifier so a few things to be aware of, think fridge.

The startup surge is a motor based surge, so the initial draw could be up a spike up to 8 times the average draw, so you need an inverter that's happy to do motor starts.

Compressor dehumidifiers are rated at warm household temperature (27 degrees in the specs you found!) and the performance will drop off quite noticeably as the temperature drops below normal house temperature. While in a small space you probably don't want to worry about extraction rates you potentially do need to worry about compressor icing which it will deal with by reversing the circuit and heating the condenser, which will generally use more power.

The good news is that the average power drops with temperature, the 10 degree rate is what I normally look at for non home use (I've used them on boats before) so you might be down to between 2-4 litres a day


So at 2 hours a day you are going to remove between 160ml - 320ml or roughly a half to full can of coke. That's not a lot for the 25Ah of battery capacity you'll use (assuming 80% inverter efficiency)

Assuming 80% DC-DC inverter efficiency the other way that's going to be about an hour of engine running at charging revs. If it wasn't for the noise on a campsite you'd be better off just running the engine and AC for that hour in the first place...


I currently have 2 Meaco desiccant units in garage/shed and a compressor unit in the house. They're great but I'd not try to run either off a battery. Mobile you are much better off just letting the warm wet air out and heating the incoming drier air.

 

[Simon Audi]

This is a van used for transporting dogs for their walk - I have 6 St Bernards - 6 Get in Van - Drive to Walking Site - 2 go for a walk - 4 stay in the van - swap over repeat - swap over repeat - drive home.

So the van is not running when parked... just the Dehumidifer will be running (hopefully) to try and minimise the condensation

When I get home - if needed - daily I can plug in the 12V charger (25A) to keep it charged and running

This week - I have been using mains when I get home (nothing when out) and its taken between 30 and 90 minutes to dry the Van Back out. of their condensation and I guess its around 200ml water thats been collected in that time.

 

[Simon Audi]

I should add that the van is always hot after about 5 minutes - due to the huge walking radiators.... so it may mean that for the first 5 minutes as you say the dehumidifier does not work - but I guess when its started the natural dog heat will keep the temperature up enough...

I guess time will tell....... but maybe I need to be ordering a bigger Inverter...