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How to wire a channel

Strip 8 mm, insert, screw down, tug-test. Same six-step action on every channel — the two onboard the Nexus hub, and every channel on a Mini, Mid or Max router. Once you've done one channel you've done them all. About 90 seconds per channel.

Close-up of a screw-clamp terminal during wiring: stripped wire approaching the wire-entry hole on the right, slotted screwdriver descending from above with a clockwise rotation arrow, and three numbered callouts — strip 8 mm, insert fully, tighten clockwise. A grommet is pre-fitted on the cable.
Screw-clamp terminal · same on every channel — Nexus hub and every router

Read this first — the bit everyone skips

Slide a strain-relief grommet onto every cable BEFORE you strip or terminate it. The grommet won't fit over a bared/screwed-down end. If you skip this step you'll have to cut the wire and start over.

The grommet ships open on one side. Open it, lay the cable in, snap it shut. One per cable. Do this for every cable now, before you do anything else.

Push every cable through its tent port BEFORE terminating for the same reason — you can't fish a terminated cable through a small port without unscrewing it again.

What you'll need

Channel map — what plugs into which channel

The Nexus hub has two onboard channels — enough to run a single tent on its own. Need more? Plug in a router: Mini adds 2 channels, Mid adds 4, Max adds 8, and you can daisy-chain up to 66 channels across as many as 16 rooms.

Set the role of each channel in the dashboard, then wire to match. Don't wire to one channel and assign another — if you do, your "extract" command spins your humidifier.

ChannelWhereTypical role
CH1Nexus (onboard)Extract fan
CH2Nexus (onboard)Intake fan
CH3Router channelCirculation
CH4Router channelLED dimmer
CH5Router channelSecond room — extract
CH6Router channelSecond room — intake
...Router channels(continues per room as you add routers)

The wiring action — once per channel, six steps

This is the same on every channel — the two onboard the Nexus hub and every channel on a router. The diagram above shows it once.

  1. Strip 8 mm of insulation from the wire end. Twist the strands together so no whiskers stick out.
  2. Loosen the channel's screw with the flat screwdriver — anti-clockwise, ¼ turn. Don't fully remove it.
  3. Push the stripped wire fully into the wire-entry hole on the front face. You'll see the copper disappear into the green terminal.
  4. Tighten the screw clockwise until firm. Don't crush the wire — stop when you feel resistance, plus a quarter turn.
  5. Tug-test. Pull the wire firmly. If it slips out, you under-tightened or didn't strip enough. Re-do.
  6. Repeat for the other pole of the same channel — every channel has + and − terminals.

That's it. Same six steps for every channel — on the hub and on every router.

Polarity & wire colours by load type

The wiring action is the same; what plugs in is different per load. Here's the standard convention:

Load+ terminal− terminalNotes
4-pin computer fan (PC-style)Red (V+)Black (GND)Yellow speed-signal wire stays unconnected; the blue sensor wire is trimmed flush
3-pin DC fanRed (V+)Black (GND)The yellow / blue sensor wire is trimmed flush
Variable-speed duct fan (AC Infinity Cloudline et al.)Red (dim +)Black (dim −)Cut off the original phone-style controller plug; cap unused wires
LED light dimmerDim + from driverDim − from driverMains power goes to the wall socket separately — never wire mains into the hub or a router
Humidifier / heater / CO₂Don't wire direct — use a BudMaster smart plug, paired in the dashboardMains-rated devices go through plugs, not channels
Power inputRed striped wire from 12 V adapterPlain wireSame screwdriver action; the power pair is the rightmost terminal on the hub and on each router

Power on, verify each channel

Wire everything cold (no power), then:

  1. Plug the 12 V adapter into the wall.
  2. Open budmaster.local in any browser on the same network. (See the WiFi setup guide if this is your first time.)
  3. Set CH1 to 50%. The extract fan should spin within 1 second.
  4. Test each channel the same way. The LED dimmer changes brightness, not RPM.
  5. Set everything back to 0% when satisfied. Turn on Auto Mode at the top of the dashboard. The hub now runs your VPD / DLI / circulation schedule automatically.

Common mistakes (the ones that cost an evening)

MistakeSymptomFix
Forgot the grommet"Cable pulls on the terminal, won't seal at the tent port"Cut wire, re-thread grommet, re-terminate
Reversed polarity (red/black swapped)Fan doesn't spin, no damageSwap the two wires
Stripped too much insulationBare copper visible outside terminalCut, re-strip clean to 8 mm
Stripped too littleLoose contact, intermittentLoosen screw, pull wire out, strip another 4 mm
Over-tightened the screwStranded wire crushed flat, intermittentLoosen, twist strands, re-insert, gentle tighten
Wired LED mains into a dimmer channelTripped breaker, possibly damaged hardwareMains goes to the wall socket. The dimmer channel is signal-only — low-voltage, safe-touch
Mixed channel orderWrong load responds to wrong commandRe-wire to match the channel-map table
Sensor wire on a 3-pin fan inserted"It buzzes, won't run smoothly"Cap or trim the sensor wire — BudMaster doesn't read it
Forgot to thread cable through tent port FIRSTTrying to fish terminated cable through 6 mm portCut wire, re-thread, re-terminate
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