Actisense NMEA 2000 Micro Bulk Cable Reel - 100M

If you're building or extending an NMEA 2000 network from scratch, this is the cable that lets you do it right. The Actisense A2K-BULK-100M is a 100-meter reel of NMEA 2000 Micro (Lite) cable, the same spec Actisense uses across its connector range, so you cut exactly the backbone length your boat needs instead of stringing together pre-made sections and hoping the run comes out clean.

Inside the jacket you get five conductors: a red and black power pair, a blue and white data pair, and a drain wire. The drain ties into a foil shield that wraps the whole bundle, and that's the part that matters on a busy boat. It knocks down radio frequency interference coming off your VHF, radar, and inverter, and it keeps the bus itself from radiating noise into everything else. On a network carrying engine data, GPS, wind, and depth all at once, that shielding is what keeps your chartplotter from dropping sensors at the worst possible moment.

The electrical spec is straightforward. It's rated 60V DC and 3A, so a single backbone comfortably powers and talks to a full helm of instruments. The data pair is 24 AWG with a 120 ohm characteristic impedance, which is exactly what the CAN bus behind NMEA 2000 wants to see for clean signaling. The power pair steps up to 22 AWG, 19-strand tinned copper, to hold voltage on longer runs. Tinned copper throughout, because this is going on a boat and bare copper and salt air don't get along.

A few numbers to plan your install around. You can build a backbone up to 100 meters long on Lite cable. Each drop cable off that backbone tops out at 6 meters, and the total of all your drops added together can't exceed 72 meters. Stay inside those limits and the network just works. Push past them and you'll start chasing intermittent dropouts that are miserable to diagnose. If your boat genuinely needs a backbone longer than 100 meters, extend the center of the run with heavier Mini cable and keep the Lite sections out on the ends.

Here's the install advice we give every customer buying bulk cable. Unroll the reel flat on the deck or the dock before you start routing, then feed it through conduit and around bulkheads from there. Pull it straight off a spinning reel and you'll kink it, and a kinked data pair is a signal problem waiting to happen. The 6.85 mm jacket is flexible and slips through tight conduit better than the fatter Mini cable, but that thinner jacket is also easier to crush, so don't force it under a hard clamp or a sharp edge.

This is bulk cable, so it ships bare on the reel with no connectors attached. You terminate it yourself with Actisense Field Fit Connectors or land it into a QNB-1 Quick Network Block. Field connections are where saltwater gets in, so seal every joint. Heat-shrink over the connector and a dab of dielectric grease on the pins goes a long way toward a network that's still solid three seasons from now. And don't forget the two terminating resistors, one at each end of the backbone. A network with only one terminator, or none at all, will give you reflections and flaky data no matter how good the cable is.

One more thing worth knowing: the cable is rated for -25 to +75 degrees C operating temperature, with an even wider storage range. That covers everything from a cold winter layup to a hot engine room in July, so you don't have to think twice about routing it near machinery spaces as long as you keep it clear of direct exhaust heat.

Who's this for? Riggers and serious DIY owners wiring a fresh electronics package on a 30 to 60 foot boat, anyone repowering a helm and adding sensors, and shops that build a lot of networks and want cable on hand to cut to fit. It's UL certified and NMEA 2000 approved, so it passes survey and plays nicely with the rest of the certified network hardware. Buy the reel, cut what you need, and keep the rest on the shelf for the next job.