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Nature's Head Standard Composting Toilet wiring diagram

See the Nature's Head Standard Composting Toilet connection points and wiring example. Open the diagram in Crimp to add your equipment and plan the cables between them.

Open this example as a new project. Use your own parts and cable lengths to make the plan yours.

Cable sizing for this example

Use the diagram as a starting point for your installation. Replace the example equipment and cable lengths with your own, and check the connections against your exact model's instructions.

3 m one way

12 V system

Wire
1.5 mm² · 16 AWG
Example fuse
2 A
Design current
0.1 A
Voltage drop
0.0%

Sized against ABYC E-11. The design current is the part's continuous draw. The length is one way; voltage drop includes an equal-length return.

Run-length and manufacturer assumptions

The editable example uses 3.048 m (10 ft) runs unless a shorter run is stated. Metric overviews round these to 3 m. Adapt the parts and lengths to your installation before choosing cable and protection.

The example uses a 2 A fuse, within Nature's Head's specified 2–5 A range. The 0.07 A load is the continuous ventilation fan; keep ventilation powered as directed and verify the actual run and polarity. Manufacturer installation manual

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Wiring diagram

How the Standard is wired.

Open this example in Crimp to use your own parts and cable lengths. Review the assumptions and installation notes as you adapt the circuit.

Nature's Head Standard Composting Toilet wiring diagram, 1.5 mm² (16 AWG) positive feed protected by a 2 A fuse and a matching negative return between the 12 V battery bank and the unit.

The example uses a 2 A fuse, within Nature's Head's specified 2–5 A range. The 0.07 A load is the continuous ventilation fan; keep ventilation powered as directed and verify the actual run and polarity. Manufacturer installation manual

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Installation notes

Connections and installation requirements.

Guidance for this model, with sources linked beside the relevant advice.

Verified against the manufacturer's documentation (rev. Nature's Head User Guide 2025 download; ©2023 manual), checked 2026-10-01. Manufacturer documentation →

What is the electrical load?

The standard Nature's Head separating composting toilet uses a small 12 V ventilation fan. The electrical data, PDF page 14 / printed 12, gives 0.07 A, equivalent to 1.68 Ah per day with continuous operation. The catalog treats the fan as always on. The mixing handle is manual and adds no electrical demand.

That page also prints an instantaneous wattage inconsistent with its current and daily energy figures. The catalog retains the stated 0.07 A and does not copy that wattage typo into the power data. At 12 V, 0.07 A would be 0.84 W by calculation.

How should the fan be powered?

The wiring instructions, PDF page 13 / printed 11, call for 2–5 A circuit protection. A 2 A branch fuse is within this published range. Use the supplied fused lead when connecting directly to a battery and keep polarity correct. A mains outlet requires the appropriate 12 V adapter; never connect the fan directly to mains. The 0.07 A terminal envelope represents operating demand, not the upstream fuse or a connector rating.

What does installation need besides power?

The ventilation and mounting instructions, PDF pages 4–7, route ventilation to an exterior sidewall or roof vent, with appropriate weather protection. A van floor vent is not the specified arrangement. Keep the vent run within the manual's 20 ft limit, support any extensions and avoid crushing the hose. Leave approximately 1.5 in behind the toilet for tilting the top and 2 in at the side needed for sliding removal. Check access with both containers actually removed before fixing the base.

How should it be used and checked?

Prepare the compost medium damp, not saturated, and keep liquids separated as the guide describes. Run the fan continuously during use and the associated drying period. For an absence of more than about a week, follow the guide's storage procedure; excessive drying can harden the contents. If airflow stops, check the fuse, polarity, plug and hose path. The fan must face the intended direction, and overtightened mounting screws can bind it. Keep cleaning liquids out of the fan and electrical connections, and empty each container according to the manual and local disposal arrangements.

Build it out

Connect it to the rest of your system.

Add Standard to your diagram, then connect your batteries, chargers and loads. Crimp calculates cable sizes and checks the connections as you draw.

Every cable you draw there is sized against ABYC E-11, from the same tables as the reference on this page.

Technical reference

Specifications, terminals and supporting parts.

Check the model, ratings and connection points against your own unit before choosing installation hardware.

Catalog specification

Nominal voltage
12 V
Compatible systems
12 V
Continuous draw
0.1 A

Supporting parts

  1. 6.1 m total of 1.5 mm² (16 AWG) marine cable
  2. Terminations for 1.5 mm² cable, matched to the equipment's screw terminals, leads or studs
  3. 2 A fuse and holder on the positive run
  4. Heat-shrink, strain relief and terminal boots sized to the cable

Check stud sizes, fuse type, run length and how warm the space gets against the gear you actually have before you order.

Terminal map

Catalog connection points, current direction and planning limits. Check the manufacturer's pinout and connector ratings before installation.

+

pos

positive · input

0.07 A

−

neg

negative · input

0.07 A

Method & provenance

Where the specifications and sizing come from.

Manufacturer specifications describe the equipment. Crimp calculates cable results from the circuit and assumptions you enter.

From the maker

What the catalog says

Manufacturer, model, ratings and which terminal does what come from the catalog. A newer revision, or the nameplate on the unit in your hand, can say something different — when it does, the nameplate wins.

ABYC E-11

What Crimp worked out

Sized against ABYC E-11. Boats built to UK or EU rules answer to ISO 13297 — check these figures against it before you build. The run length and the current above are what drive the result. Crimp doesn't know how warm your space gets; draw the cable inside an engine-bay zone on the canvas and it sizes for the heat.

Read how the sizing works

Next step

Plan your installation with Standard.

Open this example as a new project. Add your equipment and cable lengths, then review the sizing and checks for your setup.