Promag 10 Low Flow Cutoff Function Overview
Low Flow Cutoff is a key signal processing function of the Promag 10 electromagnetic flowmeter. When the fluid velocity in the pipe is below the set threshold, the instrument automatically forces the flow output to zero, avoiding false flow readings caused by empty pipe, bubbles, or static fluid. Correctly setting this parameter is crucial for improving measurement accuracy and system stability.
Based on the Promag 10 operating interface, this article introduces the low flow cutoff setup process and recommended parameters step by step, suitable for engineering commissioning and procurement selection reference.
Detailed Setup Steps
The Promag 10 is configured through the on-site display module or commissioning software. The following is the general operating procedure.
1. Enter the Parameter Setup Menu
- Ensure the instrument is in measurement mode, then press the "E" key to enter the main menu.
- Use the "+" or "-" keys to select "Setup", then press "E" to confirm.
- Select "Process Parameter", then press "E" to enter.
- Find the "Low Flow Cutoff" option.

2. Set the Cutoff Value
- Press the "E" key to enter the low flow cutoff value editing state.
- Use the "+" and "-" keys to modify the value. The unit is the same as the flow unit (such as m³/h or L/min).
- Press the "E" key to confirm, then press "ESC" to return to the measurement interface.

3. Save and Verify
- After modification, wait 10 seconds or save manually. The parameter is automatically written to non-volatile memory.
- Observe the current flow display. When the actual flow is below the set value, the output should return to zero.
- If it does not return to zero, check whether empty pipe detection is enabled or whether other compensation settings exist.

Recommended Parameters and Typical Applications
The low flow cutoff value is usually set to 1% to 5% of full scale, depending on process requirements. The table below provides reference values for common nominal diameters.
| Nominal Diameter (DN) | Recommended Cutoff Value (m³/h) | Applicable Scenario |
|---|---|---|
| DN25 | 0.05~0.15 | Small flow batching |
| DN50 | 0.2~0.6 | General process control |
| DN100 | 0.8~2.5 | Water treatment, circulating water |
| DN200 | 3.0~10.0 | Large diameter metering |
Note: If the cutoff value is too low, false accumulation may occur; if it is too high, small flow measurement accuracy will be lost. It is recommended to set it in combination with the on-site empty pipe detection function.
Common Problems and Precautions
- Cutoff value does not take effect: Check whether the "Low Flow Cutoff" function is enabled. Some versions require activating this option first.
- Large flow fluctuation: Appropriately increase the cutoff value, or check grounding and shielding to eliminate interference.
- Conflict with totalizer: After cutoff, the totalizer stops. Confirm whether the process allows this.
- Unit consistency: The cutoff value unit must be the same as the main flow unit; otherwise, the value is invalid.
Correctly setting the Promag 10 low flow cutoff can significantly improve the system's anti-interference capability, especially suitable for working conditions with intermittent flow or easy empty pipe.