Promass 80 Empty Pipe Detection Setup Guide

Overview of Promass 80 Empty Pipe Detection Function

Empty Pipe Detection (EPD) is an important diagnostic function of the Promass 80 Coriolis mass flowmeter, used to determine whether the measuring tube is in an empty state. When the pipeline is not completely filled with medium, the flowmeter may output incorrect measurement values. Enabling EPD can effectively avoid such false measurement. This function is particularly suitable for batch control, pump protection, and working conditions with gas-liquid two-phase flow.

Promass 80 identifies empty pipe status by monitoring changes in the vibration characteristics of the measuring tube. When an empty pipe is detected, the transmitter triggers an alarm or outputs a preset safe value, ensuring safe and reliable process control.

Preparation Before Setup

Hardware and Working Condition Confirmation

• Confirm that the flowmeter is correctly installed and the measuring tube is completely filled with medium or can simulate an empty pipe state.
• Check that the transmitter power supply is normal and the display panel is operable.
• Ensure that the medium conductivity meets EPD requirements (usually requires ≥5 µS/cm; refer to the manual for details).

Parameter Access Permissions

• Entering the transmitter menu requires the professional-level password (refer to the accompanying documentation for the default value).
• It is recommended to record the original parameters for easy restoration.

Empty Pipe Detection Parameter Configuration Steps

Step 1: Enter the Setup Menu

1. Press the "E" key to enter the main menu.
2. Use the "+" or "-" keys to select the "Setup" menu.
3. Press "E" to confirm and enter the submenu.

Step 2: Enable Empty Pipe Detection

1. Select the "Empty Pipe Detection" option.
2. Set the function to "On".
3. Set the response time as needed (recommended 1–5 seconds, depending on the working condition).

Step 3: Adjust Sensitivity

Promass 80 provides multiple sensitivity levels to adapt to different media and pipeline conditions. Too high sensitivity may cause false alarms, while too low sensitivity may miss detection.

Step 4: Set Alarm and Output

• Select the alarm type for empty pipe: fault, warning, or off.
• Set the safe output value: such as 0 mA, 22 mA, or hold last value.
• Save the settings after confirmation.

Commissioning and Verification Methods

Simulated Empty Pipe Test

1. Empty the measuring tube and ensure no residual medium remains.
2. Observe whether the transmitter display triggers the empty pipe alarm.
3. Check whether the current output changes according to the set value.

Actual Working Condition Verification

• Under normal full-pipe conditions, confirm that there is no empty pipe alarm.
• If false alarms occur, appropriately reduce sensitivity or extend the response time.

Common Issues and Precautions

Common Issues

• Empty pipe detection does not trigger: Check whether the medium conductivity is too low or the sensitivity setting is too small.
• Frequent false alarms: May be caused by gas in the medium or large flow fluctuations. It is recommended to adjust the response time or sensitivity.
• Unable to enable EPD: Confirm that the transmitter firmware version supports this function.

Precautions

• Empty pipe detection cannot completely replace the low flow cutoff function; it is recommended to use them together.
• In media prone to crystallization or adhesion, regularly clean the measuring tube to ensure detection accuracy.
• After modifying parameters, be sure to perform zero point calibration to ensure measurement accuracy.

Summary

Correctly setting the empty pipe detection function of Promass 80 can significantly improve the reliability of flow measurement and prevent false measurement due to empty pipes. By reasonably selecting sensitivity, response time, and alarm output, it can adapt to various industrial scenarios. It is recommended that engineering technicians record parameters after commissioning and verify them regularly to ensure long-term stable operation.