12V Ignition Wire

[Scylth]

Morning all,

I have settled on a Redarc BCDC1225D as my LiFePO4 battery charger. Since the 200 has a variable voltage alternator, they highly recommend connecting the Redarc "blue wire" to a vehicle wire that is only on when the ignition is on.

Any suggestions? The 12V outlet and cigarette lighter seem to be on during accessory mode, which isn't recommended (but are some of the easiest to identify). I'm looking for a wire that easy to identify, and not tied into anything critical - like the actual ignition. Also, needs to be a wire that "weekend" electrician to get to and splice into reasonably easy.

Thanks in advance.

 

[CharlieS]

I have AGM batteries with my BCDC, so didn't need to do this with the blue wire, but I have my SwitchPros connected to ignition for a similar purpose. I used an add-a-fuse to the IGN fuse in the engine bay fuse box.

Switchpro 9100 wiring

forum.ih8mud.com

 

[indycole]

Another option to consider would be leaving the blue wire open and using something like a battery switch between your primary and the charger. I used to rely on the blue wire but it was still easy to fool the charger when I was charging my primary with solar.

 

[RobW0]

Morning all,

I have settled on a Redarc BCDC1225D as my LiFePO4 battery charger. Since the 200 has a variable voltage alternator, they highly recommend connecting the Redarc "blue wire" to a vehicle wire that is only on when the ignition is on.

Any suggestions? The 12V outlet and cigarette lighter seem to be on during accessory mode, which isn't recommended (but are some of the easiest to identify). I'm looking for a wire that easy to identify, and not tied into anything critical - like the actual ignition. Also, needs to be a wire that "weekend" electrician to get to and splice into reasonably easy.

Thanks in advance.

Are you sure your 200 has a variable voltage alternator? I think the LC has a TCA (temperature compensating alternator). No need for the blue wire with a TCA.

 

[Scylth]

Another option to consider would be leaving the blue wire open and using something like a battery switch between your primary and the charger. I used to rely on the blue wire but it was still easy to fool the charger when I was charging my primary with solar.

I am planning on putting a switch near my right knee to do just that, @indycole. But, one of my goals is make this system as maintenance free as possible, so if I can easily tap into an “ignition”, I’m wanting to do that.

 

[Scylth]

Are you sure your 200 has a variable voltage alternator? I think the LC has a TCA (temperature compensating alternator). No need for the blue wire with a TCA.

I think you are right, from my 5 minutes of searching the internet, it appears to be temp compensated, not variable voltage. I believe the main purpose of the blue wire is to turn the Redarc charger on. By connected this to an “ignition only” on scenario, connecting that blue wire would ensure the charger doesn’t draw down my main battery.

 

[Scylth]

I have AGM batteries with my BCDC, so didn't need to do this with the blue wire, but I have my SwitchPros connected to ignition for a similar purpose. I used an add-a-fuse to the IGN fuse in the engine bay fuse box.

Switchpro 9100 wiring

forum.ih8mud.com

Do you some specific directions on how to do this, tapping into a fuse box? That sounds like a great idea, but without detailed instructions, I wouldn’t trust myself to do the work.

 

[CharlieS]

I used a product called Add-a-Fuse. It plugs into the place where the fuse (IGN in this case) goes, it has a second fuse for the new load you are adding. It essentially splits a single fuse into two separate circuits.

Here is an example: Amazon product ASIN B007FFG5YI

The 200 series uses ATM low profile mini fuses, but the mini size Add-a-fuse works fine too.

 

[Scylth]

I used a product called Add-a-Fuse. It plugs into the place where the fuse (IGN in this case) goes, it has a second fuse for the new load you are adding. It essentially splits a single fuse into two separate circuits.

Here is an example: Amazon product ASIN B007FFG5YI

The 200 series uses ATM low profile mini fuses, but the mini size Add-a-fuse works fine too.

That almost looks too good to be true. Just so I understand, you found a 12v, similar amp fuse, that was energized only when the ignition was on?
Next question: can you send me a pic of where you installed, or tell me circuit?

 

[CharlieS]

I think you are right, from my 5 minutes of searching the internet, it appears to be temp compensated, not variable voltage. I believe the main purpose of the blue wire is to turn the Redarc charger on. By connected this to an “ignition only” on scenario, connecting that blue wire would ensure the charger doesn’t draw down my main battery.

 

[HRTROB]

On mine there is an unused plug by the battery that gets +12v when the key is in position 2

Where to find switched 12V under the hood?

forum.ih8mud.com

 

[CharlieS]

That almost looks too good to be true. Just so I understand, you found a 12v, similar amp fuse, that was energized only when the ignition was on?
Next question: can you send me a pic of where you installed, or tell me circuit?

@Scylth - if you click the link I posted in post #2 of this thread, it will take you to a picture of my fuse box. It really is a simple way to add a circuit like this.

It is the fuse labeled "IGN".

 

[catastrofe]

Morning all,

I have settled on a Redarc BCDC1225D as my LiFePO4 battery charger. Since the 200 has a variable voltage alternator, they highly recommend connecting the Redarc "blue wire" to a vehicle wire that is only on when the ignition is on.

Any suggestions? The 12V outlet and cigarette lighter seem to be on during accessory mode, which isn't recommended (but are some of the easiest to identify). I'm looking for a wire that easy to identify, and not tied into anything critical - like the actual ignition. Also, needs to be a wire that "weekend" electrician to get to and splice into reasonably easy.

Thanks in advance.

FYI, I have. BCDC1240. Redarc in Australia advised that the LC200 does not have a variable alternator and the blue wire is not required. From Todd Simpson at Redarc:

“ Hello Bob.
Thank you for the enquiry.
Your vehicle has a temperature compensating alternator, sort of halfway between a smart and fixed voltage alternator. Fortunately, the temp comp alternators in Toyota’s do not drop below the turn on voltage of a BCDC (13.2v). So to cut a long story short, you do NOT need to wire the BLUE wire to ignition. You can leave this wire disconnected and tapped back.
I hope this helps Bob.”

 

[tonyc1050]

Morning all,

I have settled on a Redarc BCDC1225D as my LiFePO4 battery charger. Since the 200 has a variable voltage alternator, they highly recommend connecting the Redarc "blue wire" to a vehicle wire that is only on when the ignition is on.

Any suggestions? The 12V outlet and cigarette lighter seem to be on during accessory mode, which isn't recommended (but are some of the easiest to identify). I'm looking for a wire that easy to identify, and not tied into anything critical - like the actual ignition. Also, needs to be a wire that "weekend" electrician to get to and splice into reasonably easy.

Thanks in advance.

to answer your question, it is a Black wire with red stripe from ignition switch thru the fuse until it gets to the relay and from the relay to the ECU it is a Black with white stripe