7 Core Trailer Cable — 3mm & 4mm

Q: What does “7 core” actually mean?
Seven-core trailer cable bundles seven individually insulated copper conductors inside one black outer sheath, one core for each trailer circuit (tail lights, stop/brake lights, left indicator, right indicator, reverse lights, electric brakes and earth), so you run one cable instead of wiring each circuit separately.

Q: What's the difference between the 3mm and 4mm sizes?
These are Tycab's nominal cable sizes, not the outside diameter. 3mm is a 1.13mm² conductor (14/0.32mm strands) rated to 10A per core. 4mm is a 1.84mm² conductor (23/0.32mm strands) rated to 15A per core. The larger 4mm size carries more current, which matters for electric-brake loads and longer tow-vehicle-to-trailer runs.

Q: What's the current rating for each core?
3mm carries up to 10A per core, 4mm carries up to 15A per core, each of the seven cores rated individually, not combined. This covers standard trailer lighting loads. Electric brakes draw more on their dedicated core, so check your brake controller's rated draw against the 4mm rating on longer runs.

Q: What's the colour code for the 7 cores?
This cable follows the AS 2513 colour code used on Australian 7-pin round trailer plugs: white = earth, yellow = left indicator, brown = tail/clearance lights, red = stop/brake lights, green = right indicator, black = reversing lights, blue = electric brake control. Matching these colours at both the vehicle and trailer plug keeps the wiring consistent end to end.

Q: What crimp terminals do I need?
Match the terminal's insulation colour to the cable size: red insulated terminals (rated 0.5–1.5mm²) suit the 3mm cable, blue insulated terminals (rated 1.5–2.5mm²) suit the 4mm cable. Terminals aren't included, this is cable only, sold per metre.

Q: What voltage is this cable rated for?
Up to 120V DC or 50V AC per AS/NZS 3808 V90 PVC insulation. That comfortably covers 12V and 24V trailer, caravan and camper systems, it isn't rated for 240V AC household mains wiring.

Q: What insulation does it use, and how hot can it get?
V90 PVC insulation to AS/NZS 3808. Rated to 75°C in continuous use, or up to 105°C where the cable is protected from mechanical damage.

Q: Is this genuinely Australian-made cable?
Yes. It's manufactured in Australia by Tyree Cable (trading as Tycab), using oxygen-free copper conductors.

Q: Is it RoHS compliant?
Yes, RoHS compliant, no restricted hazardous substances in the insulation or conductor.

Q: Does it come with a trailer plug or connector?
No, this is cable only, sold per metre. You'll need a matching 7-pin trailer plug/socket for your tow vehicle's connector type, plus crimp terminals, to complete the wiring.

Q: Can I use this for a caravan, or is it just for light trailers?
Yes, the same 7-core cable and colour code is used for light trailers, box trailers and caravans. For caravans running electric brakes over a longer tow-vehicle-to-van run, use the 4mm size to keep voltage drop and heat down on the higher-draw brake core.