---
title: Control Box
description: "The Control Box is a compact unit with a **start button**, **arc switch** and **emergency stop** for simple operation of SmoothTool X from the workpiece. Add it as an external device so SmoothTool X can read and drive its signals.…"
url: "https://hub.smooth-robotics.com/docs/getting-started-external-devices-control-box/"
updated: "2026-09-23"
category: Getting Started / External Devices
---

# Control Box

The Control Box is a compact unit with a **start button**, **arc switch** and **emergency stop** for simple operation of SmoothTool X from the workpiece. Add it as an external device so SmoothTool X can read and drive its signals.

## Add the Control Box

1. Open **SmoothTool X Settings** and tap **External devices** under **Components**, then tap **Add external device**. Select the **Control Box** tile.

 ![Add external device — Control Box tile](https://hub.smooth-robotics.com/wp-content/uploads/2026/09/manual-getting-started-external-devices-control-box-select.webp)

1. Assign the I/O signals for the box:

   - **Start button** — the digital input the start button is wired to.
   - **Start button light** — the digital output that lights the start button.
   - **Arc switch** — the digital input for the arc switch.
2. Tap **Done** to add the Control Box.

 ![Control Box — signal configuration](https://hub.smooth-robotics.com/wp-content/uploads/2026/09/manual-getting-started-external-devices-control-box-settings.webp)

1. The Control Box now appears in the **External devices** list.

 ![External devices — Control Box added](https://hub.smooth-robotics.com/wp-content/uploads/2026/09/manual-getting-started-external-devices-control-box-added.webp)