Redarc BCDC1225

Submitted: Sunday, Dec 01, 2013 at 19:37
ThreadID: 105336 Views:7365 Replies:5 FollowUps:2
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I have a couple of questions to ask re the above dc to dc charger.
I have a Toyota Prado and tow a caravan and I am considering purchasing the above charger to charge my van batteries. (2x100 amp agm batteries)
Should the charger be installed in the Prado or in the caravan battery compartment?
I understand that it will charge from both alternator and solar inputs.
I have 150 watts of portable solar which I would like to connect when I am camped for extended periods of time.
Is it just a matter of unplugging an anderson type plug from the car to caravan and then plugging in my solar panels to the van anderson type plug?
Does the Redarc unit recognise the input change or is there something that needs to be done manually?


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Reply By: Maggsie - Sunday, Dec 01, 2013 at 21:34

Sunday, Dec 01, 2013 at 21:34
log in to the Redarc website and all your questions will be answered there, including wiring diagrams for different applications. I have the 1240 and no problems.

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AnswerID: 522435

Reply By: Brian 01 - Sunday, Dec 01, 2013 at 21:59

Sunday, Dec 01, 2013 at 21:59
The device needs to be positioned as close as practicable to the battery that is being charged. This is so that any voltage drop that takes place in the wiring occurs in the input side and can then be compensated for in the output side.
Whilst the charger will compensate for input voltage drop, you still need to provide sufficient cable size between the car and van to minimise this.
It will charge from both solar and alternator, but not at the same time.
You can do it the way you suggest by swapping the anderson plugs, or via separate inputs and a relay.
If using the anderson plug swap method, you will connect the red wire to the positive and the black to the negative, you will also need to either install a switch that will connect the blue wire to the red wire when charging from the car and break that connection when charging from the solar, or run the blue wire through to the car (via the regular 7/12 pin plug) and connect it to the accessory terminal of the ignition or to the alternator feed on the car side of the anderson plug.

The relay method is better in that it does this automatically.
The blue wire can be connected to an ignition/accessory source on the car, whereupon alternator charging will be the default with solar taking over when the ignition is off
OR, it can be connected to the 12v alternator input from the car.
If connected to the 12v input from the car, then the solar will not operate unless the Anderson plug is disconnected from the car (or you have some other method of disconnection of the car battery from the van such as a solenoid or VSR).
Terminate the orange separately for charging your AGM battery.
Suitable circuit diagrams are supplied with the charger.
Don't use 24v solar panels as the Redarc is rated to only 32v and a 24v panel has an Ocv in excess of that.
AnswerID: 522437

Reply By: Andrew D. - Wednesday, Dec 04, 2013 at 09:14

Wednesday, Dec 04, 2013 at 09:14
Had the Redarc BCDC1225 and was never that satisfactory. Friend had same experience. Changed to Ctek D250S Dual with inbuilt MPPT solar regulator and charged and maintained the batteries perfectly. If you compare specifications you can see the charging profile of the Ctek is superior.
AnswerID: 522542

Follow Up By: olcoolone - Wednesday, Dec 04, 2013 at 13:20

Wednesday, Dec 04, 2013 at 13:20
FollowupID: 803636

Follow Up By: Andrew D. - Wednesday, Dec 04, 2013 at 13:28

Wednesday, Dec 04, 2013 at 13:28
olcoolone have they closed down all the establishments for mental defectives in SA? Your displayed issues are alarming and need professional treatment.
You have proven your lack of knowledge time and time again so don't make matters worse.
Sign up for some basic electrical and English education if you cannot understand specifications.
FollowupID: 803637

Reply By: Bob Y. - Qld - Thursday, Dec 05, 2013 at 12:53

Thursday, Dec 05, 2013 at 12:53

I was looking at getting either the 1225 or 1240, but decided against it because of the need to wire in a relay, for latching between alternator power and solar.

Instead I bought a Redarc BMS, which has DC/DC charger, MPPT solar reg and a 240v 15 amp multistage charger. Doesn't need a changeover relay, and has a remote display to keep track of power use etc. Bit exxy(>$1K), but the cost of seperate, good quality items would be almost same cost.


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AnswerID: 522592

Reply By: Nomadic Navara - Friday, Dec 06, 2013 at 00:31

Friday, Dec 06, 2013 at 00:31
Chris, with 200 Ah battery capacity I would be inclined to go for one of the Redarc 40 A models. You need to get near C/4 charging capacity to recharge your batteries when they are very low in capacity.
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AnswerID: 522636

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