3 B&S ignition relay lead — 25mm² cable, 120A Anderson, 6 metres

This 3 B&S ignition relay lead carries 12V or 24V power to the back of your vehicle — a fridge, a compressor, or a DC-DC / BC-DC charger — and only powers up when it should. The built-in ignition-sensing relay closes when your ignition is turned on, letting power flow from the main battery, and opens when you switch off so the lead can’t drain the battery while you’re parked. It’s built on heavy Australian-made 3 B&S (25mm²) twin-core cable over 6 metres for low voltage drop, and terminated with a 120A Anderson-style plug. Assembled ready to wire in: relay, fuse, lugs and ignition wire all included.

How the ignition relay works

The lead runs through an ignition-sensing 100A relay. Wire the thin ignition trigger wire to a switched (ignition-on) source using the included fuse taps, and the relay closes with the key on — power flows through the main 3 B&S cable to your Anderson plug. Turn the key off and the relay opens, depowering the lead. That means no parasitic drain on the crank battery when the vehicle is off, and a clean trigger for DC-DC and BC-DC chargers that should only draw while the engine is running.

Key features

• Heavy Australian-made 3 B&S (25mm²) twin-core, double-insulated cable, 6m — low voltage drop
• Ignition-sensing 100A relay — closes with ignition on, opens when off to depower the lead
• 120A Anderson-style plug for a secure, high-current connection
• 100A Midi fuse and holder for circuit protection (upgradeable on request)
• Full-length split-tube protection (6m) against rubbing and cuts
• Two heavy-duty 10mm ring cable lugs for a clean battery-end termination
• 3m × 4mm ignition wire with mini and standard fuse taps included

Specifications

What it suits

Ideal for DC-DC and BC-DC charger systems, dual-battery setups, and running power to the rear of a vehicle for a fridge, compressor or camp setup. The ignition-sensing relay makes it a clean match for charger installs that should only draw from the crank battery while the engine is running. The 120A Anderson-style plug suits common auxiliary and dual-battery fitments, and the heavy 3 B&S cable keeps voltage drop low over the 6-metre run. The lead is relay-switched and fused at 100A, with the 120A plug giving headroom on the connector.

Build options

• Cable length can be made to suit — contact us for a quote on a custom run
• Fuse rating can be changed to match your setup
• Anderson plug colour can be changed to Blue or Red. Please leave a note in the cart if that is required

Australian Made

This lead is built with a majority of Australian-made components and assembled by hand in our Queensland workshop. Our 12/24V premade lead range carries Australian Made accreditation — so you’re getting a quality, locally built product and supporting an Australian small business at the same time.

Built to spec. Made for the track.