# C02 Del.Total
### Definition
Set the flow meter’s totalizer to zero manually. Default: No.
### Notes
N/A
### Operation Procedure
Button Functions(Click to Expand)
When the main screen is displayed in **green backlight**, the four buttons function as follows:
* **Blue Button (leftmost):** Return, exit, or save settings.
* Gray Direction Buttons:
* **Left Gray:** Previous Page, decrease value, or select item
* **Right Gray:** Next Page, increase value, or select item
* **Orange Button (rightmost):** Rightmost button: Enter settings, edit, or confirm selection
{% hint style="danger" %}
**Do not hold buttons for extended periods to avoid damage.**
{% endhint %}
{% hint style="info" %}
Button functions may change depending on the operation context to improve usability or prevent accidental presses.
{% endhint %}
```
C02 Del. Total Setting Steps
• From the main screen (green backlight),
press Orange Button (Setup) to enter settings (orange backlight).
• Use Gray Arrow Buttons to select C. Total , press Orange Button (Enter).
• Use Gray Arrow Buttons to select C02 Del. Total, press Orange Button (Enter).
• Use Gray Arrow Buttons to choose the options.
• Press Orange Button (Set) to confirm.
• Press Blue Button (ESC) to return to the main screen (green backlight).
```
### C02 Options – RS485 Values, Read/Write Commands, and Format
| Option | Description | RS-485 Value |
| ------------ | --------------- | ------------ |
| No (Default) | No Reset | 0 |
| Yes | Reset Totalizer | 1 |
> Refer to the [Read/Write Memory List](https://docs.lorric.com/qr/fu-es-echosense-instruction-manual/communication/modbus-rtu-protocol/read-write-memory-ram/read-write-memory-read-list) for the Modbus command format. \
> The data type for this parameter is **Int16**.
#### RS485 Remote Totalizer Reset (C02 Del. Total)
| Item | Description |
| ---------------- | ---------------------------- |
| Parameter Name | C02 Del. Total |
| Description | Resets the Totalizer to zero |
| Register Address | 02 01 |
| Register Length | 1 |
| Data Type | int16 |
| Read Command | Function Code 03 |
| Write Command | Function Code 06 |
#### 1.Read Current Status (Function Code 03)
The master can use Function Code 03 to read the current status of C02:
* Return value = `0`: Not triggered (default)
* Return value = `1`: Reset action triggered
#### 2.Execute Totalizer Reset (Function Code 06)
The master can use Function Code 06 to write a specified value to the C02 register to trigger the reset:
* Write Value: `1` (Int16)
* After writing, the device immediately resets the Totalizer to zero.
**Orange Button (rightmost):** Rightmost button: Enter settings, edit, or confirm selection
{% hint style="danger" %}
**Do not hold buttons for extended periods to avoid damage.**
{% endhint %}
{% hint style="info" %}
Button functions may change depending on the operation context to improve usability or prevent accidental presses.
{% endhint %}
