Decreased Pump Capacity Detection

The function notifies users when there is a decrease in capacity for one or several pumps in the station

Decreased pump capacity detection is a function for wet well pumping stations. The function notifies users when there is a decrease in capacity for one or several pumps in the station. The function distinguishes between sudden and gradual losses of capacity. The capacity loss can be a result of issues with the pump or with the surrounding equipment, for example, pipes, couplings, and valves. The function suits pumps that run in cycles between constant start and stop levels, with regular stops.

The function needs the following data:

• Pump status
• Analog water level

The function calculates the capacity of a pump once each pump cycle. The calculation adjusts for inflow to the wet well during the pump cycle. If a pump cycle starts more than one pump, then the function cannot calculate the pump capacity.

There are two alarms and two graphs for each pump. The alarms and graphs show information about two measurements:

Measurement	Description	Possible cause
Short-term decreased pump capacity	This measurement detects sudden decreases in pump capacity.	Clogged pump hydraulics or non-return valve  Malfunctioning non-return valve Leaking coupling on the delivery pipe
Long-term decreased pump capacity	This measurement detects slow decreases in pump capacity. The user sets a checkpoint, for example when the pump is installed or overhauled. The checkpoint is the starting date for the time period that the function uses as reference for capacity loss.	Worn pump hydraulics Gradual clogging of the pump hydraulics or the delivery pipe Issues with the non-return valve

The alarms activate when the capacity is lower than the configured threshold. The thresholds are a percentage value of the average pump capacity. It is possible to change the threshold values in the settings.

The sales representative can enable this function. This function does not support variable-frequency drive pumps.