quick charging question

Nekarsulm

Hi all, we have a 2000 Autoroller '5. While plugged in to the mains, the leisure batteries recharge. The engine battery does not. Is this normal procedure? I left the courtesy light on for 24 hours and ran down the main engine battery. Regards, new.

Yeah think so. Easily remedied with a conductor and switch or relay. I just use two chargers though.
A voltage sensing relay driver would do everything at once from all directions but is still a bit limiting because you're linking mismatched batteries and the charger is only really catering for the nearest/strongest one.

I've a relay driver going for a song if you're interested...I've mostly put all the magic smoke back into it except the disconnect trimpot setting is stuck at 13.1v iirc.

Nekarsulm

Ha! You lost me after the magic smoke bit!
Jump leaded it (the Positive pole is awkward enough on the Ducato) and it's grand now. Thanks. Nek

Nekarsulm

Magic smoke is the most vital component of any piece of electronics...soon as it escapes; device stops working. It's very trixy to get it back in there but possible if you're persistent and have enough junk.

Actually it's the connect threshold I've lost the adjustment on. It's supposed to be presentable; connect (relay...when either battery sees..) from 13.0v to 13.6v, disconnect from 12.6v - 13.3v, and hold state for 0 -90 secs....except the magic smoke in charge of the connect threshold has done a legger and it's locked at 13.1v...
...can't remember what I did exactly but something to do with bench testing it with unbridled conductors and bodgineering...:o

Any other takers?
Going twice...(for a song!)

....I may poke it a bit more at some stage. I'm trying to google design a latching version instead for purpose.

Nekarsulm wrote: »

Jump leaded it (the Positive pole is awkward enough on the Ducato) and it's grand now.

That's all you need really...put a switch in the middle and call it hard-wired. :pac:

niloc1951

I have ONE OF THESE fitted.
It sends a charge to the engine battery from the leisure battery when it (the leisure battery) reaches 13,6 volts.
It works whatever the source of charge to the leisure battery, hook-up or solar.

niloc1951

niloc1951 wrote: »

ONE OF THESE

Charge current 4A max :eek:
Disconnect @ 12.5v

You can do better Niloc!
Here did I mention I have a relay driver for sale? :pac:

Link





Link

[Edit]: Better Link

niloc1951

Sir Liamalot wrote: »

Charge current 4A max :eek:
Disconnect @ 12.5v

You can do better Niloc!
Here did I mention I have a relay driver for sale? :pac:

It works for me
It is not for primary charging of the starter battery, it's more for countering the effects of using the dash radio and any other small loads or losses while stationery.

With solar panels working it keeps the starter battery healthy while off hook up.

Yeah just teasing Niloc.

Looks alright in fairness 4A is loads for a starter battery, plus I bet your B2B charger is back feeding it. [Edit: so it's a good thing it's current limited].
Conductors look a bit small but that voltage drop isn't significant
My concern would be the disconnect threshold is too low for a system that's idling without a hook-up or engine cranking as the starter will be held in parallel until you turn a load on the house batteries.
Is it solid state? Any diode drop across the unit?

niloc1951

Sir Liamalot wrote: »

Yeah just teasing Niloc.

............................Is it solid state? Any diode drop across the unit?

Haven't a clue, the unit is sealed (filled with a type of resin or some such stuff) all its innards can't be seen or got at.

On the plus side CBE are a major supplier to the motorhome manufacturing trade, their stuff is standard on Rapido and other quality brands so the CSB2 unit should tick all the required boxes.

It probably is solid state if it's potted. There'll be a voltage drop somewhere between 0.7v and 1.5v from the input to output. That or they put a SMD relay in there and they don't want people tinkering with it made it waterproof. It also won't click. You can check it easily by comparing the battery voltages at the terminals and compensate for wiring losses and battery SOC.
Solid state relays aren't the may west for charging circuits.
I try to avoid motorhome stuff to be honest, most of my kit is for industry and off grid.