Dual battery setup

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This is there fix:

Ctekfix.jpg
 
so when the alt is showing low current it automatically switches to solar????
what if you have no solar?
i installed a ctec d250s dual for a mate not long ago
he also had permanent solar on roof
there was no relay involved?
alt imput and solar were each connected to unit seperatly
the unit simply switched to solar charging when ign is off
i believe the redarc senses low volts from eco alt but still charges when ign is on
http://www.redarc.com.au/images/uploads/images/BCDC1225-LV_Instruction_Manual.pdf
 
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so when the alt is showing low current it automatically switches to solar????
what if you have no solar?
i installed a ctec d250s dual for a mate not long ago
he also had permanent solar on roof
there was no relay involved?
alt imput and solar were each connected to unit seperatly
the unit simply switched to solar charging when ign is off
i believe the redarc senses low volts from eco alt but still charges when ign is on

this is how i plan to do it have done it twice without the relay on mates cars. that drawing seems wrong as theres a alternator input and a solar input.... putting a relay in to switch when the ignition is off would defeat the purpose of having the smart charger....?

ok so back to my thing i plan on using one of these big cat batterys as space is not an issue and i can guarantee you with fridge and other shit i run including lights amps pumps and inverters 200ah is a safe bet

http://www.cat.com/cda/files/3049510/7/PEHJ0073-02.pdf

i am looking at the 153-5710 first page of them. can anyone see anything more suited among this list.?
 
so when the alt is showing low current it automatically switches to solar????
what if you have no solar?
i installed a ctec d250s dual for a mate not long ago
he also had permanent solar on roof
there was no relay involved?
alt imput and solar were each connected to unit seperatly
the unit simply switched to solar charging when ign is off
i believe the redarc senses low volts from eco alt but still charges when ign is on
http://www.redarc.com.au/images/uploads/images/BCDC1225-LV_Instruction_Manual.pdf

Looking at that diagram, the relay is set up so that when the ignition is on the alternator is sending power to the battery all the time, then the solar kicks in when the key is off. Obviously if no solar then no charging when the key is off
 
Looking at that diagram, the relay is set up so that when the ignition is on the alternator is sending power to the battery all the time, then the solar kicks in when the key is off. Obviously if no solar then no charging when the key is off

it also states low ignition it wont charge?
 
I was thinking low as in off, but I can see your point... It does seem like a weird setup though if that's the way they try and sell them...
 
I'v never seen a full starter that has any ah, just ca & cca. Battery like Yellow top as duel use so they have deep cycle ah, ca/cca not alot of amp hours tho. 200ah is alot you'll probably never need that much. But better to go a full deep cycle battery.



Had a felling you'd say that. Makes most duel battery system useless

If you look at almost any battery you'll find either an RC (reserve capacity, the number of minutes the battery can maintain a useful voltage while delivering 25A) or an Ah (the number of amps per hour you can draw for 20 hours before the battery falls below 10.75V = dead flat). Some say the RC is a better gauge of capacity than the Ah - but the RC value (remember, that's minutes) will often be around double the Ah rating, so you can generally figure one from the other.

For auxiliary purposes these are more important than CCA, which is the number of amps the battery can deliver for 30 seconds at 0F (zero degrees Fahrenheit). It's also easier to work out capacity in Ah - so that's generally what I'll use. I prefer simple math.

Now on to those dual battery issues with the new alternators - there are new isolators that deal with it. Look for them in the Redarc range at least (I think they're the model with the 'i' in the model number).
 
If you look at almost any battery you'll find either an RC (reserve capacity, the number of minutes the battery can maintain a useful voltage while delivering 25A) or an Ah (the number of amps per hour you can draw for 20 hours before the battery falls below 10.75V = dead flat). Some say the RC is a better gauge of capacity than the Ah - but the RC value (remember, that's minutes) will often be around double the Ah rating, so you can generally figure one from the other.

For auxiliary purposes these are more important than CCA, which is the number of amps the battery can deliver for 30 seconds at 0F (zero degrees Fahrenheit). It's also easier to work out capacity in Ah - so that's generally what I'll use. I prefer simple math.

Now on to those dual battery issues with the new alternators - there are new isolators that deal with it. Look for them in the Redarc range at least (I think they're the model with the 'i' in the model number).

cheers mate. also if you have two batterys same ah one starter one deep cycle is there really a difference? that diagram seems whack still its basically saying put the alternator onto the solar input and nothing onto the alternator input on the charger.
 
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It's basically a standard double pole relay wired in reverse so it switches input based on the state of the ignition. Ignition on and it activates the relay, closing the circuit between the alternator and the CTek charger. Switch the ignition off and the relay clicks off, returning to the default solar->charger. It makes sense if you know how solar chargers work.

The C-Tek charger is designed to take fluctuating inputs on the solar input and manage that into a usable power source for charging. The alternator input of the CTek expects a fairly consistent input (probably hard-wired in the range of 14.1-14.7V). I guess that means they don't have to reinvent the wheel and can just draw power from the cranker until the alternator figures it needs to juice it up again.

The one warning I'd make with this one: don't leave your car in ACC ON (or ignition on, engine off) for extended periods of time, because it will draw power from the starter without stopping.
 
so when the alt is showing low current it automatically switches to solar????
what if you have no solar?
i installed a ctec d250s dual for a mate not long ago
he also had permanent solar on roof
there was no relay involved?
alt imput and solar were each connected to unit seperatly
the unit simply switched to solar charging when ign is off
i believe the redarc senses low volts from eco alt but still charges when ign is on
http://www.redarc.com.au/images/uploads/images/BCDC1225-LV_Instruction_Manual.pdf

Reading it what I understand is that the low cut out is lower then most. So the red arc will keep working even when the alt is in in lazy mode
 
The one warning I'd make with this one: don't leave your car in ACC ON (or ignition on, engine off) for extended periods of time, because it will draw power from the starter without stopping.


So basically do without the relay and run straight to solar pole on the charger??
 
It's basically a standard double pole relay wired in reverse so it switches input based on the state of the ignition. Ignition on and it activates the relay, closing the circuit between the alternator and the CTek charger. Switch the ignition off and the relay clicks off, returning to the default solar->charger. It makes sense if you know how solar chargers work.

The C-Tek charger is designed to take fluctuating inputs on the solar input and manage that into a usable power source for charging. The alternator input of the CTek expects a fairly consistent input (probably hard-wired in the range of 14.1-14.7V). I guess that means they don't have to reinvent the wheel and can just draw power from the cranker until the alternator figures it needs to juice it up again.

The one warning I'd make with this one: don't leave your car in ACC ON (or ignition on, engine off) for extended periods of time, because it will draw power from the starter without stopping.

That makes sense, well kinda. Thinking its better to just get the redarc that is designed for it or tho the price is a different matter.

So basically do without the relay and run straight to solar pole on the charger??

I think then you may damaged the charge.
 
Reading it what I understand is that the low cut out is lower then most. So the red arc will keep working even when the alt is in in lazy mode

thats the way i read it
i would go with the redarc if you have an eco alternater
 
the 1st amount of voltage is like 14v then in drop down. But could be wrong. I like the redarc as its made for it
 
here is redarcs low voltage dc/dc charger

This is about as good as gets for a dual battery system solution, with many four wheel drivers and people towing a vehicle set up with 2 different battery technologies ( start battery being lead acid ) and the auxiliary battery being another , say AGM , it is difficult to get long life or full charge our of the second/auxiliary battery.
THIS IS THE SOLUTION , the BCDC12225LV is a battery isolator and a 3 stage battery charger in one Isolating the start battery with the ignition off and a BOOST , FLOAT and ABSORPTION charger This unit will also compensate for low voltage wiring to it and the auxiliary battery DOES NOT RELY on the alternator to receive it's charge rate which in a lot of cases is not the optimum anyway, So if you need more battery capacity from your system consider this as an alternative you may have enough , just the Auxiliary battery may not be getting it's full charge.This unit also features MPPT ( maximum power point tracking ) solar regulator for connecting in with a solar panel system as well.


cheaper on ebay,same wty from factory
i can reccomend this seller
have bought heaps from him with no issues
http://www.ebay.com.au/itm/REDARC-B..._Parts_Accessories&hash=item5d39d0525a&_uhb=1
 
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Thanks guys the red arc will be the the way I'm going. O and no relay on the 250s means no way to disconnect the 2 batteries.
 
so an AGM requires a different charger? and the cars alternator wont charge an AGM correctly??
 

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