Unexpected Variations in Water Level

Application

This anomaly type is applicable to wastewater pumping stations that are equipped with an analog level sensor.

Description

Users are notified of this anomaly if the measured water level decreases repeatedly when no pump is running.

Possible causes

• A fault in or other issues with the analog level sensor
• A fault in the controller
• An issue with the non-return valve of the pump
• Incorrect station configuration in Avensor

Related charts for evaluation

For instructions on where to find the related charts for examination, see
"Where do I find the anomaly charts for examination?" under Event FAQs > Anomalies.

Description of the chart First day the anomaly was detected

The chart shows the following data:

• The running status of each pump in the station on the first day that the anomaly was detected
• The water level on the first day that the anomaly was detected

The chart allows the user to evaluate the issue that has caused the anomaly.

Description of the chart Current state of the station

The chart shows when the anomaly is active. The chart shows the following data:

• The running status of each pump in the station during the previous 24 hours
• The water level during the previous 24 hours

The chart allows the user to evaluate the current state of the station.

If the anomaly has ceased, only the chart First day the anomaly was detected shows.

Evaluation of charts, example 1

The station has two pumps that are set to alternate regularly and to run between constant start and stop levels. The charts show that the measured water level is very noisy, which makes the pump cycles hard to differentiate. This trend indicates a fault in the analog level sensor.

In this example, the situation is especially serious because the faulty level sensor measures unrealistic level spikes, which start the pumps. Right after, the sensor measures a level that is less than the configured stop level and thus stops the pumps. This behavior results in hundreds of unnecessary cycles every day for both the pumps, which start and stop in a quick succession.

Evaluation of charts, example 2

The measured water level is consistent with a regular pump operation between the configured start and stop levels. At the same time, the utilization of the pumps is constantly equal to zero, which does not correspond to the trend of water level. This behavior indicates an issue with the configuration of the station in Avensor, rather than with the station itself.

Disable the anomaly type

If the behavior that is identified as an anomaly is normal for a station, the anomaly type should be disabled. For more information, see "How do I enable or disable an anomaly type?" under Event FAQs > Anomalies.