Method for self-adjustment of a pump settings in a swimming pool filtering circuit

Abstract

The proposed method includes an initial checking step, during which a pump of a filtering circuit is operated at a given checking operation frequency meanwhile a pump checking operation value is measured, and using the measured data a calculation of the water flow rate when pump operates at a given operation frequency lower than the given checking operation frequency is performed. The pump is then operated at said given operation frequency for a first filtering period of time. When said period is concluded the checking step, at checking frequency, is newly performed obtaining a new checking operation value, and this value is used to calculate a required operation frequency necessary to produce a flow rate equal to the initially calculated flow rate, and the pump is operated at said new calculated operation frequency for a second filtering period of time.

Claims

1. Method for self-adjustment of a pump settings in a swimming pool filtering circuit, comprising a closed water circuit through which the water is constantly circulated except when a cleaning operation or change of a filter occurs, said pool filtering circuit including: a pool; a filter; a centrifugal electrical pump with either an integral or external electronic frequency converter, said centrifugal electrical pump constantly circulating water through the closed water circuit; the method comprises following steps performed in following order: a) calculate a flow rate produced operating the pump at a predefined operation frequency, and operate the pump at said predefined operation frequency during a first filtering period of time; after concluding said filtering period of time, b) to calculate a pump operation frequency necessary to pump water at said flow rate; and operate the pump at said calculated pump operation frequency during a second filtering period of time; characterized in that the method further comprises: c) previous to said step a), operate the pump at a predefined checking frequency during a checking period of time, being the filter at an initial cleanness state and being the operation frequency lower than the checking frequency, producing a checking flow rate; measure a pump checking operation value during said checking period of time and use said measured pump checking operation value to perform the calculation of step a); d) after concluding said first filtering period of time operate the pump at said predefined checking frequency during a checking period of time producing a checking flow rate; measure a new pump checking operation value during said checking period of time; and use said measured new pump checking operation value to perform the calculation of step b), after concluding said second filtering period of time steps b) and d) are repeated iteratively, obtaining different checking operation values on each iteration due to the fact that the filter offers as time goes on an increasing resistance to the flow, and therefore calculating different pump operation frequency on each iteration to keep said flow rate calculated on step a) constant, and generating an event when said checking operation value measured on step d) exceed a given threshold.

2. Method according to claim 1, wherein said pump checking operation value and said new checking operation value is the current intensity consumed by the pump.

3. Method according to claim 1, wherein said pump operation frequency is comprised between 15 and 25 Hz and/or said pump checking frequency is comprised between 40 and 50 Hz.

4. Method according to claim 1, wherein said predefined operation frequency is 20 Hz.

5. Method according to claim 1, wherein said filter is a sand filter.

6. Method according to claim 1 wherein said checking period of time is between 30 seconds and 5 minutes.

7. Method according to claim 1 wherein said first and said second filtering period of time are equal.

8. Method according to claim 1 wherein said first and/or second filtering period of time are between 20 and 120 minutes.

9. Method according to claim 1 wherein said event is the creation of an alarm signal.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The foregoing and other advantages and features will be more clearly understood based on the following detailed description of an embodiment in reference to the attached drawings which must be interpreted in an illustrative and non-limiting manner, in which:

(2) FIG. 1 shows a schematic sectional view of a swimming pool filtering circuit including a pool, a filter, and a centrifugal electrical pump with either an integral or external electronic frequency converter that constantly circulates water through the closed water circuit at a given flow rate;

(3) FIG. 2 shows schematic flow chart of the operation method described.

DETAILED DESCRIPTION OF AN EMBODIMENT

(4) FIG. 1 shows by way of non-limiting illustrative example a method for self-adjustment of a pump settings in a swimming pool filtering circuit.

(5) The proposed filtering circuit comprises a closed water circuit through which the water is constantly circulated but when a cleaning operation or change of a filter 3 occurs, including a swimming pool 1, a sand filter 3 and a multistage centrifugal pump 2 activated by an electric motor and controlled by an integral or external electronic frequency converter.

(6) The filtering circuit includes a first pipe connecting said swimming pool 1 with the pump inlet, a second pipe connecting the pump outlet with the filter inlet, and a third pipe connecting the filter outlet with the swimming pool 1. An additional dumping pipe can be connected to the second or third pipes through a valve, permitting dumping water from the circuit.

(7) The proposed method starts with an initial step c), during which the pump 2 is operated during a checking period of time Tc at a checking frequency N of 50 Hz, absorbing water from the swimming pool 1 through said first pipe, forcing said water through the sand filter 3, which is at an initial cleanness state, and returning the filtered water to the swimming pool 1 through the third pipe.

(8) Said initial step c) is performed through a clean or new filter 3 having optimal initial cleanness state, and being said checking period of time Tc 3 minutes long.

(9) The current intensity consumed by the electric motor of the pump during said checking period of time Tc, called on this embodiment pump checking operation value I, is measured by a sensor integrated on the electronic frequency converter connected to the electric motor of the pump 2. Said data are communicated to a PLC also integrated on said electronic frequency converter, which store a function which allows said PLC to calculate during step a) the flow rate Q50i produced by said pump 2 operated at the predefined checking frequency N of 50 Hz and consuming the measured current intensity consumed, and using said flow rate Q50i calculated the PLC can calculate the flow rate QN1i produced operating the pump at any other operation frequency different to the checking operation frequency. Also during step a) said PLC calculates the flow rate QN1i produced by the pump 2 operating at a predefined operation frequency N1 stored on the PLC memory, in this example 20 Hz, which is a preferred efficient operation frequency, and stores the calculated flow rate QN1i on the PLC memory.

(10) Next the pump 2 is operated at said predefined operation frequency N1 of 20 Hz during a first filtering period of time T1 (for example 1 hour) during the step a) of the method.

(11) When said first filtering period of time N1 concludes the sand filter 3 will offer an increased resistance to the flow of water through it, and therefore the flow rate at the end of said first filtering period of time will be lower than the flow rate at the beginning of said first filtering period of time.

(12) At this point, step a) is concluded and step d) is performed operating the pump at the checking operation frequency N (50 Hz) during said checking period of time Tc (3 minutes), producing the increase of the flow rate and also the increase of the checking operation value I (current intensity consumed) to a higher level compared with the operation value during said first filtering period of time T1 allowing a precise measuring of said checking operation value I. Using this data and during step b) said PLC calculates a new operation frequency Nn necessary to produce a flow rate equal than the initial calculated flow rate QN1i stored on the PLC memory.

(13) Next the pump 2 is operated at said new calculated operation frequency Nn during a second filtering period of time T2 performing step b), producing a flow rate equal than the flow rate QN1i produced during the first filtering period of time T1.

(14) When said second filtering period of time T2 has ended, the steps b) and d) of said method are repeated iteratively, being the initial cleanness of the filter 3 worst on each iteration, producing a reduction of the flow rate on each iteration, and requiring a higher operation frequency Nn on each iteration.

(15) This method is reproduced multiple times until the checking operation value I exceeds a predefined threshold, and then an event is triggered.

(16) Said event will be preferably stopping the pump, or creating an alarm signal, or implementing a filter cleaning operation, for example a backwash operation.

(17) Different frequencies and times are also contemplated.

(18) FIG. 2 shows a schematic flow chart of the operation method described wherein letter N represents the pump operation frequency, letter I represents the pump operation value, and letter Q represents the flow rate value.