> 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/alarms-and-system-status.md).

# Alarms and System Status

{% hint style="info" %}
Bits are numbered from right to left, starting with **Bit 0** on the far right.\
A bit value of **1** indicates an active alarm or status. Refer to the table below for system status descriptions.
{% endhint %}

## **Alarm A – Critical Failure**

Triggered during flow sensing errors or main unit failures.\
The LCD backlight flashes **red**.

**Alarm A Error Code Definition:**\
Bits are defined from **MSB (Bit 7)** to **LSB (Bit 0)**, with each bit representing the following:

<table><thead><tr><th width="112.9921875">Bit</th><th width="220.361328125">Alarm Definition</th><th width="153.59765625">Alarm Code</th><th>Trigger Condition</th></tr></thead><tbody><tr><td>7</td><td>NA</td><td></td><td></td></tr><tr><td>6</td><td>NA</td><td></td><td></td></tr><tr><td>5</td><td>NA</td><td></td><td></td></tr><tr><td>4</td><td>NA</td><td></td><td></td></tr><tr><td>3</td><td>NA</td><td></td><td></td></tr><tr><td>2</td><td>NA</td><td></td><td></td></tr><tr><td>1</td><td>NA</td><td></td><td></td></tr><tr><td>0</td><td>Ultrasonic Sensor Communication Error</td><td>D01</td><td>Caused by a power supply issue or sensing module damage. Verify the power supply. If the error persists, return the unit for factory service.</td></tr></tbody></table>

![](https://3404778090-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fi4ECt41Kyy9211OWazj4%2Fuploads%2FF0pMh7q5gzR2vx7xfnXA%2FFU-LT-Alarm-A-diagram-en.jpg?alt=media\&token=5aba6b37-02fb-4cf5-9a14-5ccb4ca1168a)

***

## **Alarm B – Out of Specification**

Used for flow beyond the set range or other conditions requiring attention. Configurable under **D** parameter category.\
The main screen LCD backlight turns **solid red** when active.

**Alarm B Error Code Definition:**\
Bits are defined from **MSB (Bit 7)** to **LSB (Bit 0)**, with each bit representing the following:

<table><thead><tr><th width="126.1611328125">Bit</th><th>Alarm Definition</th><th>Alarm Code</th><th>Trigger Condition</th></tr></thead><tbody><tr><td>7</td><td>Dosing target reached</td><td>D16</td><td><p>Dosing target reached</p><p></p></td></tr><tr><td>6</td><td>Totalized flow exceeds target</td><td>D09</td><td>Totalized flow exceeds or falls below the preset target <mark style="color:red;">*Note</mark></td></tr><tr><td>5</td><td>Value exceeds analog output upper limit</td><td>D12</td><td>Value exceeds the analog output upper limit</td></tr><tr><td>4</td><td>Value below analog output lower limit</td><td>D12</td><td>Value falls below the analog output lower limit</td></tr><tr><td>3</td><td>Flow velocity > 6 m/s or &#x3C; –6 m/s</td><td>D13</td><td>Flow velocity > 6 m/s or &#x3C; –6 m/s</td></tr><tr><td>2</td><td>OCT timing too slow</td><td>D14</td><td>(OCT pulse count + 1) exceeds the limit</td></tr><tr><td>1</td><td>Instantaneous flow above upper limit</td><td>D05</td><td>Instantaneous flow above upper limit</td></tr><tr><td>0</td><td>Instantaneous flow below lower limit</td><td>D05</td><td>Instantaneous flow below lower limit</td></tr></tbody></table>

<mark style="color:red;">\* Note</mark>

```
D09, D10, D11 Cumulative Alarm Description

Example 1: Positive Flow
Enable the D09 cumulative alarm, and set the D10 cumulative condition to "Greater than target".
Set the D11 cumulative target to a positive number, such as +100.
When the cumulative positive flow exceeds 100, the system will trigger the cumulative alarm.

Example 2: Negative Flow
Enable the D09 cumulative alarm, and set the D10 cumulative condition to "Less than target".
Set the D11 cumulative target to a negative number, such as -500.
When the cumulative negative flow is less than -500, the system will trigger the cumulative alarm.
```

![](https://3404778090-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fi4ECt41Kyy9211OWazj4%2Fuploads%2Fa61S72ncj5qBNUgrRt2R%2FFU-LT-Alarm-B-diagram-en.jpg?alt=media\&token=acc297f1-4eb6-46e2-a1b1-ced269e7ec49)

***

### Alarm – C: Maintenance Required

Used to indicate that the flowmeter requires maintenance. Configurable under the Maintenance/Diagnostic category.\
The main screen LCD backlight turns solid red when active.

\
**Alarm C Error Code Definition:**\
Bits are defined from MSB (Bit 7) to LSB (Bit 0), with each bit representing the following:

| Bit | Alarm Definition                                 | Alarm Code | Trigger Condition                                                                                                                        |
| --- | ------------------------------------------------ | ---------- | ---------------------------------------------------------------------------------------------------------------------------------------- |
| 7   | NA                                               |            |                                                                                                                                          |
| 6   | NA                                               |            |                                                                                                                                          |
| 5   | NA                                               |            |                                                                                                                                          |
| 4   | NA                                               |            |                                                                                                                                          |
| 3   | Poor ultrasonic signal                           | D03        | Signal strength at 0 bars.                                                                                                               |
| 2   | NA                                               |            |                                                                                                                                          |
| 1   | excessive line impedance or no wiring connection | D15        | Excessive line impedance or no wiring connection on Iout (0/4–20 mA) = 1, normal = 0. Parameter D14 must be set to On or Do Not Disturb. |
| 0   | NA                                               |            |                                                                                                                                          |

![](https://3404778090-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fi4ECt41Kyy9211OWazj4%2Fuploads%2FYsT9X0lGDnMmOX5FlNZb%2FFU-LT-Alarm-C-diagram-en.jpg?alt=media\&token=83d631c5-d099-4034-98f1-511300bd0ae1)

***

### **System Status**

Status codes are defined from MSB (Bit 7) to LSB (Bit 0), with each bit representing the following:

<table><thead><tr><th width="75.740234375">Bit</th><th width="170.7197265625">Alarm Definition</th><th width="97.8291015625">Alarm Code</th><th>Trigger Condition</th></tr></thead><tbody><tr><td>7</td><td>NA</td><td></td><td></td></tr><tr><td>6</td><td>NA</td><td></td><td></td></tr><tr><td>5</td><td>NA</td><td></td><td></td></tr><tr><td>4</td><td>NA</td><td></td><td></td></tr><tr><td>3</td><td>NA</td><td></td><td></td></tr><tr><td>2</td><td>NA</td><td></td><td></td></tr><tr><td>1</td><td>NA</td><td></td><td></td></tr><tr><td>0</td><td>OCT Status</td><td></td><td><p>OCT Status</p><ul><li>NC - Normally Closed (allows current flow) shows “1”</li><li>NO - Normally Open (no current flow) shows “0”</li></ul><p>E01 is set to NC by default. Alarm S value = 1</p></td></tr></tbody></table>

![](https://3404778090-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fi4ECt41Kyy9211OWazj4%2Fuploads%2Fs6NDJwE2eQvIWy5sbX4i%2FFU-LT-Alarm-S-diagram-en.jpg?alt=media\&token=105d6169-5311-4139-9062-da7c226a726e)


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