> For the complete documentation index, see [llms.txt](https://docs.lorric.com/qr/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lorric.com/qr/fu-lt-english-v1/human-machine-interface-hmi/main-screen.md).

# Main Screen

The FU-LT features nine main screens. The **H09 Home Page** function allows selection of the screen displayed at startup. Detailed instructions for H09 operation are provided at the end of this chapter.

When the main screen is displayed in green backlight, the four buttons function as follows:

* <img src="/files/bdd75120acea6361d128fd3deec06f1a8277e667" alt="" data-size="line"> **Blue Button (leftmost):** No function
* Gray Direction Buttons:
  * <img src="/files/2e37e572251371c6020ab6d9e11c1fcdd5ef0369" alt="" data-size="line"> **Left Gray:** Page navigation
  * <img src="/files/50a67ff5744401e217d5b9e838da3f7909be732f" alt="" data-size="line"> **Right Gray:** Page navigation
* <img src="/files/6c0b22a2048cf9b2afd86fac7a65e414feb967d4" alt="" data-size="line"> **Orange Button (rightmost):** Switches to the **Settings screen**, changing the backlight from green to orange

## **Main Screen Menu**

### Screen 1: **Flowrate**

The first line of the LCD shows the flow unit, the second line shows **Instant Flowrate**, and the third line shows the flow signal on the lower left and **Setup** on the lower right, indicating that pressing the orange button switches to the **Settings screen**.

{% hint style="info" %}
A single-bar signal indicates a poor measurement environment, while less than one bar may be caused by air bubbles or other interference. When below one bar, **Noisy** is typically displayed. Adjusting the pipe according to installation instructions is recommended to improve the signal.
{% endhint %}

<img src="/files/ezsxrTNmzbhIt9DIlBjf" alt="" width="563">

### **Screen 2: Hybrid1**

The hybrid screen displays both **Instant Flowrate** and **Total Flow**. The first line shows **Instant Flowrate**, the second line shows **Total Flow**, and the third line shows the flow signal on the lower left and **Setup** on the lower right, indicating that pressing the orange button switches to the **Settings screen**. Instant flow units can be adjusted in [**B01 Vol. Unit**](/qr/fu-lt-english-v1/parameters/b-unit-setup/b01-vol.-unit.md) and [**B02 Time Unit**](/qr/fu-lt-english-v1/parameters/b-unit-setup/b02-time-unit.md), while total flow units can be adjusted in [**B03 Total Unit**](/qr/fu-lt-english-v1/parameters/b-unit-setup/b03-total-unit.md).

<img src="/files/NkN9jyHtaLV24gtqACIs" alt="" width="563">

### **Screen 3: Status Page**

Displays system status and diagnostics, showing **Alarm A, B, C codes** and the system **S code**. A red flowmeter indicator signals a problem requiring attention; switching to this screen allows confirmation of flowmeter abnormalities. For details, refer to [**Alarms and System Status**](/qr/fu-lt-english-v1/human-machine-interface-hmi/alarms-and-system-status.md) (original document link retained at source).

{% hint style="info" %}
Record a video or take a photo of this page for factory verification when an issue occurs.
{% endhint %}

<img src="/files/kqjL7VR5ZSeUQeriVa0t" alt="" width="563">

### **Screen 4: Dosing**

Used for batch or quantitative control (**Dosing**). The first line of the LCD shows the **Dosing Reset Time**, the second line shows **Total Flow**, and the third line shows the flow signal on the lower left and **Setup** on the lower right, indicating that pressing the orange button switches to the **Settings screen**. The dosing reset time can be adjusted in **C05 Dosing Reset Time**, and total flow units can be adjusted in **B03 Total Unit**.

<img src="/files/7FSG7A0v9hN669rW2XkE" alt="" width="563">

### **Screen 5: Total \<Large>**

Displays total flow with enlarged digits for easy viewing. The large digits show **Total Flow**, **POS** at the bottom indicates forward direction, and the lower right shows the flow unit (**L**). Pressing the orange button at the lower right switches to the **Settings screen**. Total calculation method can be adjusted in [**C01 Total Method**](/qr/fu-lt-english-v1/parameters/c-total/c01-total-method.md): **POS** (Forward), **NET** (Net), **NEG** (Reverse), and total flow units can be adjusted in [**B03 Total Unit**](/qr/fu-lt-english-v1/parameters/b-unit-setup/b03-total-unit.md).

{% hint style="info" %}
Flow in Simulation Mode is also included in the total accumulated flow.
{% endhint %}

<img src="/files/92qU9JMALG4CVfD85jGd" alt="" width="563">

### **Screen 6: Velocity \<Large>**

Displays flow velocity with enlarged digits for easy viewing. The large digits show the velocity, and the lower right displays the unit (**m/s**). Pressing the orange button at the lower right switches to the **Settings screen**. Velocity units can be adjusted in [**B04 Velocity Unit**](/qr/fu-lt-english-v1/parameters/b-unit-setup/b04-velocity-unit.md).

<img src="/files/iVzPdbmkgpCmxYZJ6BMW" alt="" width="563">

### **Screen 7: Flowrate \<Large>**

Displays **instant flowrate** with enlarged digits for easy viewing. The large digits show the flowrate, and the lower right displays the unit (**L/m**). Pressing the orange button at the lower right switches to the **Settings screen**. Flow units can be adjusted in [**B01 Vol. Unit**](/qr/fu-lt-english-v1/parameters/b-unit-setup/b01-vol.-unit.md) and [**B02 Time Unit**](/qr/fu-lt-english-v1/parameters/b-unit-setup/b02-time-unit.md).

<img src="/files/9lbXfmvFjB910DQVsemm" alt="" width="563">

### **Screen 8: Total**

The first line of the LCD shows the total flow unit (**L**), the second line displays **Total Flow**, and the third line shows the flow signal on the lower left and **Setup** on the lower right, indicating that pressing the orange button switches to the **Settings screen**. Total flow units can be adjusted in [**B03 Total Unit**](/qr/fu-lt-english-v1/parameters/b-unit-setup/b03-total-unit.md).

{% hint style="info" %}
Flow in Simulation Mode is also included in the total flow.
{% endhint %}

<img src="/files/UV5nVQzlgvBSWDZAe0ng" alt="" width="563">

### **Screen 9: Velocity**

The first line of the LCD shows the velocity unit (**m/s**), the second line displays **Velocity**, and the third line shows the flow signal on the lower left and **Setup** on the lower right, indicating that pressing the orange button switches to the **Settings screen**. Velocity units can be adjusted in [**B04 Velocity Unit**.](/qr/fu-lt-english-v1/parameters/b-unit-setup/b04-velocity-unit.md)

<img src="/files/WnVnyQlX04Q3qhOHUdIR" alt="" width="563">


---

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