# 4.3 | Power Requirements

A switched 12V DC power supply with a minimum capacity of 10A is required.

The harnessing system has been designed to provide flexibility in sourcing 12V DC switched power depending on where the ECU is mounted, and where sources of protected 12V DC power are freely available.

The following power supply options are supported:

### Cab Convenience Sockets

**COMMAND** can be powered using an available cab convenience power socket along with the T3H-F001 Power Adaptor provided by T3RRA.

<p class="callout info">**NOTE**: A minimum of two cab convenience sockets are required in total if providing power to **COMMAND** and implement harnessing, and a RuggON tablet. Three are required if adding an ISOBUS breakaway connector that requires a convenience power connection e.g. JD ISOBUS plug kit.  
  
If fewer than two convenience ports are available, another power option may need to be used for **COMMAND** or the tablet.</p>

<p class="callout danger">**WARNING**: Convenience power supply sockets should be load-dump protected and fused appropriately within tractor electrical systems, and generally are but it's always best to make sure.</p>

<table border="1" class="align-center" id="bkmrk-" style="border-collapse: collapse; width: 78.6905%;"><colgroup><col style="width: 48.9221%;"></col><col style="width: 51.0426%;"></col></colgroup><tbody><tr><td>[![image.png](https://docs.t3rra.com/uploads/images/gallery/2025-05/scaled-1680-/image.png)](https://docs.t3rra.com/uploads/images/gallery/2025-05/image.png)</td><td>[![image.png](https://docs.t3rra.com/uploads/images/gallery/2025-05/scaled-1680-/ey8image.png)](https://docs.t3rra.com/uploads/images/gallery/2025-05/ey8image.png)

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### Using a Constant Power Harness 

The Constant Power Harness (**CNH 115-0172-397/8 OR JD** **BPF10403/4**) can be connected to the **COMMAND** harnessing system at connector C6 on the **T3H-C005** exterior breakout harness.

<p class="callout info">**NOTE:** The Constant Power Harness may not possess its own fusing, but a fuse is supplied on the **T3H-C005** harness to protect against electrical faults.</p>

Connection can also be made directly into the **T3H-C002** EXT branch (Connector C6) if the **T3H-C005** is not required but the aforementioned fuse must still be added for appropriate protection using a **T3H-F003** Inline Fuse Adapter.

[![image.png](https://docs.t3rra.com/uploads/images/gallery/2025-05/scaled-1680-/4kHimage.png)](https://docs.t3rra.com/uploads/images/gallery/2025-05/4kHimage.png)

### <span style="color: rgb(0, 0, 0);">Providing a Custom Power Connection</span>


A custom connection to switched 12V power can be made using the **T3H-F002** Power Adaptor (DT06-2S &amp; Loose Wire Ends). The installing technician must provide the appropriate connections / terminations depending on their own requirements.

<p class="callout info">**NOTE**: Avoid routing power cables near high-current or noisy signals if possible (e.g. alternator).</p>

<p class="callout danger">**WARNING**: The power supply must be rated and protected appropriately for the application!</p>

#### Custom Power Supply Requirements

If a custom power source is used, it must meet the following requirements:

<table border="1" id="bkmrk-description-nominal-" style="border-collapse: collapse; width: 100%; height: 336px;"><colgroup><col style="width: 23.6136%;"></col><col style="width: 26.731%;"></col><col style="width: 49.7151%;"></col></colgroup><thead><tr style="height: 30.2812px;"><td style="height: 30.2812px;">**Description**</td><td style="height: 30.2812px;">**Nominal Range / Rating**</td><td style="height: 30.2812px;">**Notes**</td></tr></thead><tbody><tr style="height: 63.8438px;"><td style="height: 63.8438px;">***Supply Voltage (V)***</td><td style="height: 63.8438px;">9-32V DC</td><td style="height: 63.8438px;">Ripple/noise ≤ 100 mV peak-to-peak recommended; ensure **DC/DC converters** are well-filtered.</td></tr><tr style="height: 47.0625px;"><td style="height: 47.0625px;">***Supply Current (A)***</td><td style="height: 47.0625px;">1A for general ECU operation

plus 2A per proportional solenoid in use

</td><td style="height: 47.0625px;">Depends on connected loads, MCU, sensors, and interfaces.</td></tr><tr style="height: 130.969px;"><td style="height: 130.969px;">***Power Supply Protections***</td><td style="height: 130.969px;">Overvoltage protection

</td><td style="height: 130.969px;">Must be protected against load dump, inductive spikes, and cranking via TVS diodes or suppression circuits.

Transient protection required (TVS diode, suppressor per ISO 7637-2).

</td></tr><tr style="height: 63.8438px;"><td style="height: 63.8438px;">  
</td><td style="height: 63.8438px;">Overcurrent protection

</td><td style="height: 63.8438px;">Must include a fuse or circuit breaker rated to a maximum of 10A.</td></tr></tbody></table>