# K03 Scale Factor

### Definition

Sets the correction method for instantaneous flow. Default: Simple Mode, using the formula:

Corrected Instantaneous Flow = K03 × Measured Instantaneous Flow − K04

Parameters K02 (Correction Mode), K03 (Scale Factor), and K04 (Offset Flow) adjust flowmeter reading deviations.

$$
\text{Corrected Instantaneous Flow} = K\_{03} \times \text{Measured Instantaneous Flow} - K\_{04}
$$

<details>

<summary><strong>Calibration Examples (Click to Expand)</strong></summary>

**1. Error Caused by Liquid Density**

**Example – 50% Sulfuric Acid**\
Assume the liquid is sulfuric acid with a specific gravity of 1.4.\
Actual measured weight: 26 tons. The flow meter displays 20,004 L.\
Converted weight: 20,004 × 1.4 = 28,005.6 kg (≈ 28 tons) \
→ the reading is higher than the actual value.

**Step 1: Adjust the K03 scale factor**

$$K\_{03} = \frac{\text{Actual Weight}}{\text{Flow Meter Displayed Weight}}$$  =  $$\frac{26\ \text{tons}}{28\ \text{tons}} \approx 0.928$$

Set **K03 = 0.928**, then the flow meter–calculated weight ≈ **25.98 tons**, close to the true value.

**Step 2 – Fine adjustment using K04:**

* After adjusting K03, readings may be accurate at **high flow**, but small deviations can remain at **low flow** or when the pump starts.
* Adjust **K04** to compensate for fixed offset errors. For example：
* If readings consistently **exceed** the true value by **0.1 ton**, set **K04 = 0.1**, and the system will automatically subtract this from the calculated weight.
* If readings consistently **fall short of** the true value by **0.1 ton**, set **K04 = - 0.1**, and the system will automatically add this value to the calculated weight.

**2. Error Caused by Analog Output**

**Example**\
The user is using the analog output and finds that the receiving device (e.g., PLC) does not match the value shown on the flow meter.

The meter display shows **0** (no flow in the pipe), but the output current is **4.1 mA** instead of the standard **4.0 mA**.\
After conversion at the receiving end, this results in an incorrect flow reading of **0.98 L/min** (zero offset).

**Step 1: Use Simulation Mode to Check for Scaling Error**

If the displayed flow value appears incorrect (for example, a flow reading when no liquid is present), first use Simulation Mode to verify whether a scaling error exists.\
Refer to the Simulation Mode section for detailed operation.

Enable **F02 Simulation Mode**, then go to **E06** and enable the analog output content (recommended: **Flow Rate**).\
Next, enter **F01** to set the simulated flow value and observe the reading on the receiving device.

For example, when the simulated value is set to **60 L/min** but the receiving end shows **58.41 L/min**, this indicates an overall scaling error (reading too low).

*<mark style="background-color:red;">After testing with Simulation Mode, it can be confirmed that the issue is not only a zero offset, but also an output scaling error.</mark>*

**Adjust the K03 scale factor**

$$K\_{03} = \frac{\text{Actual Weight}}{\text{Flow Meter Displayed Weight}}$$  =  $$\frac{26\ \text{tons}}{28\ \text{tons}} \approx 0.928$$

Set the K03 value to 1.027. After this adjustment, the flowmeter’s converted reading shows a weight of approximately 58.42, approaching the true value of 60.

**Step 2: Eliminate the Remaining Fixed Offset (Zero Point Shift)**

After adjusting K03, the readings are accurate at high flow rates, but small deviations may still occur at low flow rates or when the pump starts at a fixed flow. To correct this **fixed offset error**, you can fine-tune the K04 value.

**Adjusting K04 to Correct Flow Values**

For example, after the user exits simulation mode and the flow returns to zero, if the receiving end still shows a reading of 0.98, set K04 to +0.98. The system will automatically subtract this value from the calculation, effectively zeroing the meter’s reading.

</details>

### Notes

* **K03** cannot accept negative values.
* To measure reverse flow, enable **A17 (Reverse Flow)**.
* **K03** serves the same function as **Z05**; users may choose either. Executing this function will automatically update the **Z05 Scale Factor** setting.

### Operation Procedure

<details>

<summary><strong>Button Functions</strong> <em>(Click to Expand)</em></summary>

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

* <img src="https://4028902321-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FSBz5Tlpy8GCIkK4ygkgZ%2Fuploads%2FRnX1fMK1ja5FUx043ZYc%2Fimage?alt=media&#x26;token=f31dd577-ba27-4369-af8b-25ce9afcd1f9" alt="" data-size="line"> **Blue Button (leftmost):** Return, exit, or save settings.
* Gray Direction Buttons:
  * <img src="https://4028902321-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FSBz5Tlpy8GCIkK4ygkgZ%2Fuploads%2FR48KXgI2flteQ78PYH8a%2Fimage?alt=media&#x26;token=b5b4ab82-6f88-44c6-8b85-181c7bde6fe9" alt="" data-size="line"> **Left Gray:** Previous Page, decrease value, or select item
  * <img src="https://4028902321-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FSBz5Tlpy8GCIkK4ygkgZ%2Fuploads%2FVWLxHCjTZgj8Y3CXUn6X%2Fimage?alt=media&#x26;token=35556f59-f963-4b03-8db1-34f2953ddb58" alt="" data-size="line"> **Right Gray:** Next Page, increase value, or select item
* <img src="https://4028902321-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FSBz5Tlpy8GCIkK4ygkgZ%2Fuploads%2F0lsHAW4cWIphk6mKtEoK%2Fbutton-orange.png?alt=media&#x26;token=9168c231-821c-4895-9194-0cf61b2fd06a" alt="" data-size="line"> **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 %}

</details>

<details>

<summary><strong>Calibration Offset Function (Click to Expand)</strong></summary>

> Used to correct flowmeter reading deviations.
>
> **Related Parameters: K02:** Calibration Scheme, **K03:** Scale Factor, **K04:** Offset Flow

K02 Calibration Scheme SelectionCurrently only Simple Mode is available. No adjustment is required.K03 Scale Factor SettingK03 Scale Factor Setting Steps• From the main screen(green backlight),   press Orange Button(Setup) to enter settings (orange backlight).• Use Gray Arrow Buttons to select K. Calibration, press Orange Button(Enter).• Use Gray Arrow Buttons to select K03 Scale Factor, press Orange Button(Enter).• Use Gray Arrow Buttons to choose the digit to adjust(highlighted in dark gray).• Press Orange Button(Edit) to enter adjustment mode.• Adjust digits: Left Gray Button to increase, Right Gray Button to decrease.• Press Orange Button(Set) to confirm each digit; repeat for other digits as needed.• After all digits are set, press Blue Button(Save).Confirm by pressing Orange Button(Save) (or Blue Button(NOT) to cancel).• Press Blue Button(ESC) to return to the main screen(green backlight).K04 Flow Offset SettingK04 Manual Offset Setting Steps• From the main screen(green backlight),   press Orange Button(Setup) to enter settings (orange backlight).• Use Gray Arrow Buttons to select K. Calibration, press Orange Button(Enter).• Use Gray Arrow Buttons to select K04 Manual Offset, press Orange Button(Enter).• Use Gray Arrow Buttons to choose the digit to adjust(highlighted in dark gray).• Press Orange Button(Edit) to enter adjustment mode.• Adjust digits: Left Gray Button to increase, Right Gray Button to decrease.• Press Orange Button(Set) to confirm each digit; repeat for other digits as needed.• After all digits are set, press Blue Button(Save).Confirm by pressing Orange Button(Save) (or Blue Button(NOT) to cancel).• Press Blue Button(ESC) to return to the main screen(green backlight).Calibrate VerificationVerify whether the calibration result meets expectations by checking if the calibrated flow value matches the target value. If not, readjust K03 (Scale Factor) or K04 (Flow Offset) and repeat steps 2–4.The system automatically calculates the calibrated instantaneous flow using the formula:\ <br>

</details>

### K02 Options, RS485 Values, Read/Write Commands, and Formats

<table><thead><tr><th>Parameter Input Range</th><th>Corresponding Values</th><th>RS-485 Value</th><th data-hidden></th></tr></thead><tbody><tr><td>Custom</td><td>1</td><td>-</td><td></td></tr><tr><td>Minimum</td><td>0.001</td><td>-</td><td></td></tr><tr><td>Maximum</td><td>1000</td><td>-</td><td></td></tr></tbody></table>

> 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. This parameter uses the float32 data format.