Does The Redarc Alpha 50A In-Vehicle BCDC Battery Charger RED78NR Need A Separate Ignition Wire?

Updated 04/29/2026 | Published 04/26/2026

Question:

I’m not clear on the need for a separate ignition wire. I have a smart alternator. The charge will be installed in a slide-in truck camper, not permanently connected to the truck. I have an Anderson connector for the charging wires, so that’s not the problem. I don’t want to run a separate ignition wire just to tell this thing to turn on. Is that what is required?

asked by: Brett

Expert Reply:

Hey Brett, thanks for reaching out. I get what you’re trying to avoid, and unfortunately with a smart alternator setup, that ignition trigger wire is there for a reason. The Redarc Alpha 50A In-Vehicle BCDC Battery Charger # RED78NR needs a reliable signal that the engine is actually running, because smart alternators don’t hold a steady voltage like older ones. Without that trigger, the charger can see low or fluctuating voltage and either not turn on consistently or shut off when you don’t want it to.

expert reply by: Jesse M