> For the complete documentation index, see [llms.txt](https://docs.rtkdata.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.rtkdata.com/integration-hub/machine-control/topcon-3d-mc.md).

# Topcon 3D-MC / MC-X1

Connect a **Topcon 3D-MC** or **MC-X1** machine control system to RTKdata.com for centimeter-level RTK positioning on excavators, dozers, and graders. Topcon machine control systems are **not locked to TopNET Live** — they accept RTCM corrections from any standard NTRIP caster.

## Key capabilities

| Feature                    | Details                                            |
| -------------------------- | -------------------------------------------------- |
| **Compatible systems**     | Topcon 3D-MC, MC-X1                                |
| **Compatible displays**    | GX-60, GX-77                                       |
| **Compatible receivers**   | MC-R3, MC-I3                                       |
| **MC-I3 connectivity**     | Internal 3G/4G modem with SIM slot                 |
| **MC-R3 connectivity**     | External modem or phone hotspot required           |
| **Locked to TopNET Live?** | No — accepts any NTRIP provider                    |
| **Correction format**      | RTCM 3.x via NTRIP                                 |
| **Configuration path**     | Topcon Logo > Tools > Configure Radios > NTRIP tab |

## Requirements

* **Topcon 3D-MC or MC-X1** machine control system
* **Display:** GX-60 or GX-77
* **Receiver:** MC-R3 or MC-I3
* **Internet connection:** MC-I3 internal modem with active SIM card, or external modem / phone hotspot for MC-R3
* **RTKdata account:** Active subscription with NTRIP credentials

{% hint style="info" %}
Don't have an RTKdata.com account yet? [Start 30-day Free Trial](https://rtkdata.com/try-rtk-corrections-free-for-30-days/) or [View Pricing](https://rtkdata.com/pricing/)
{% endhint %}

## Step-by-step setup

{% stepper %}
{% step %}

### Power on and verify internet connectivity

1. Power on the machine control system (display and receiver).
2. If using an **MC-I3**: Insert a SIM card with an active data plan into the internal modem slot. Verify cellular signal on the display.
3. If using an **MC-R3**: Connect an external cellular modem or pair with a phone hotspot for internet access.
   {% endstep %}

{% step %}

### Open the NTRIP configuration

1. On the GX-60 or GX-77 display, tap the **Topcon Logo** in the corner of the screen.
2. Navigate to **Tools** > **Configure Radios**.
3. Select the **NTRIP** tab.
   {% endstep %}

{% step %}

### Enter RTKdata.com NTRIP settings

Fill in the NTRIP connection fields:

{% tabs %}
{% tab title="North America" %}

* **Host (domain):** `rtk.rtkdata.com`
* **Host (IP fallback):** `13.56.117.10`
* **Port:** `2101`
* **Username / Password:** From *RTK Credentials* in the internal dashboard (not website login)
* **Mountpoint (ALL CAPS):** `AUTO`
  {% endtab %}

{% tab title="Europe" %}

* **Host (domain):** `eu.rtkdata.com`
* **Host (IP fallback):** `3.73.41.96`
* **Port:** `2101`
* **Username / Password:** From *RTK Credentials* in the internal dashboard (not website login)
* **Mountpoint (ALL CAPS):** `AUTO`
  {% endtab %}

{% tab title="Australia" %}

* **Host (domain):** `aus.rtkdata.com`
* **Host (IP fallback):** `54.206.56.130`
* **Port:** `2101`
* **Username / Password:** From *RTK Credentials* in the internal dashboard (not website login)
* **Mountpoint (ALL CAPS):** `AUTO`
  {% endtab %}
  {% endtabs %}

{% hint style="warning" %}
Type `AUTO` manually in ALL CAPS. Do not browse the source table — enter the mountpoint name directly.
{% endhint %}
{% endstep %}

{% step %}

### Connect and verify RTK status

1. Tap **Connect** or **Apply** to save the settings and initiate the NTRIP connection.
2. Monitor the GNSS/RTK status indicator on the display:

| Status               | Meaning                                                                   |
| -------------------- | ------------------------------------------------------------------------- |
| **Autonomous / GPS** | Basic satellite fix. No corrections applied.                              |
| **DGPS / Float**     | Correction data arriving and being processed.                             |
| **RTK Fixed**        | Centimeter-level accuracy achieved. Ready for machine control operations. |

3. Convergence to RTK Fixed typically takes **30–90 seconds** with clear sky visibility.

{% hint style="info" %}
For machine control operations, always wait for **RTK Fixed** before beginning grading, excavation, or dozing. Working in Float mode may result in elevation errors that affect cut/fill accuracy.
{% endhint %}
{% endstep %}
{% endstepper %}

## Vertical reference (heights)

{% hint style="info" %}
RTK corrections deliver **ellipsoidal heights** (height above the WGS 84 ellipsoid), not orthometric heights. For machine control, you typically work with a local site calibration or localization that accounts for the geoid. Configure the appropriate vertical datum in your Topcon project settings.
{% endhint %}

## Troubleshooting

| Problem               | Cause                            | Fix                                                                                                                                   |
| --------------------- | -------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------- |
| NTRIP tab not visible | Older firmware                   | Update the display and receiver firmware. The NTRIP tab may not appear on very old firmware versions.                                 |
| No internet (MC-I3)   | SIM card missing or no data plan | Verify the SIM card is inserted and has an active cellular data plan.                                                                 |
| No internet (MC-R3)   | No external modem connected      | Connect an external modem or pair with a phone hotspot. The MC-R3 does not have an internal modem.                                    |
| Connection fails      | Wrong host or port               | Double-check the host address for your region and confirm port is `2101`.                                                             |
| Authentication error  | Wrong credentials                | Use the username and password from your RTKdata dashboard, not your website login. Credentials are case-sensitive.                    |
| Stuck on Float        | Poor sky visibility              | Move the machine to an open area. GNSS antennas on heavy equipment can be partially obstructed by booms, cabs, and nearby structures. |
| Stuck on Float        | Receiver issue                   | Power-cycle the receiver. If Float persists, verify the receiver has an RTK-capable license/configuration.                            |
| Mountpoint error      | Wrong capitalization             | Type `AUTO` in ALL CAPS.                                                                                                              |

## Tips

* **Not locked to TopNET Live.** You can use any standard NTRIP caster, including RTKdata.com. No Topcon-specific subscription is required for the NTRIP connection.
* **MC-I3 is the simplest setup** — its internal modem with SIM slot means no external devices are needed for internet connectivity.
* **MC-R3 users** should consider a dedicated cellular modem mounted on the machine for the most reliable connection, rather than relying on a phone hotspot.
* **Site calibration is critical.** Before starting machine control work, perform a site localization/calibration to align RTK coordinates with your design surface.
* **Vibration and multipath.** Heavy equipment environments can cause multipath interference. Ensure the GNSS antenna is mounted as high and clear as possible on the machine.
* **Keep firmware updated** on both the display and receiver for the latest NTRIP client improvements and constellation support.


---

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