Packaged Pump Station FAQs
On assist will I get twice the flow rate?
The flow rate will be greater than with a single pump but due to the losses in the manifold and rising main coupled with restrictions due to the flow from the primary pump, the flow will never achieve twice the flow of a single pump.Top
My system will not run on Auto or will not run at all (new or nearly new systems)
This is likely to be due to one of three reasons:
1. The pumps may have a blockage sufficient for the current drawn to rise to a point that causes the overload(s) within the panel to trip.
2. The overload(s) may still have the supply setting and may need to be adjusted to suit the current rating of the pump.
3. The float switches may have had the cables extended using cable smaller than 2.5mm This most commonly results in the system only working in ‘Hand’ and not ‘Auto’
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What wires do I use in my float switches?
The float switches provided have 3 cores, there is a ‘common’, a ‘normally open’ and a ‘normally closed’ circuit. The systems need to be set up so that the ‘common’ and the ‘normally open’ cables are connected, when the float is hanging freely, to the panel. The standard colours used are Blue, Brown and Black. The Black is the common, the Brown is the ‘normally open’ and the blue is not used but should be isolated.Top
Where do I fit the float switches?
Pump systems that have separate float switches will have either 3 or 4 floats:
3 Float System.
Lowest float is the STOP float and should be positioned at a level about the top of the pump such that the pump remains submerged when the system has been switched off.
Middle float will be the RUN float and should be positioned at a height greater than 160mm above the STOP float but below the inlet to the chamber. The higher this is set, the longer the pump will run each cycle. The lower it is set, the more frequently the pump will operate. This is a user defined setting.
Top float will be the ALARM activation float, This should be positioned above the Start float but below the inlet to the chamber.
4 Float system
This is as above however the additional float is for an ASSIST pump in duplex pump stations. This should be positioned between the START and ALARM floats.
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Can I extend the float switch cables?
Yes but consideration must be taken on the cable size, the power supply into the control circuit and float switches is via a 24v 2Amp transformer so the operation of this will be affected if the cable size is too small as there will be volt drop. It is therefore recommended that a minimum cable size of 2.5mm is used to extend float switch cables with the connection made within the top of the chamber using an IP67 rated junction box.Top
How can I work out my discharge rate?
The discharge rate achieved by the pump systems depends on several factors including vertical lift, rising main length, number and type of bends and valves, rising main material and of course, the ability of the pump. All applications need to be assessed individually.
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Is there any benefit in using a grinder pump?
Grinder or macerator pumps generally offer an increased flow capacity for a given head, when compared to the equivalent vortex pump. In addition to this, they have the ability to break down solid matter before it is pumped. They suit applications where 3 phase power is available as the torque required to overcome material already within the grinder at start up. Single phase pumps can very fail during repeated start ups.
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What diameter does my rising main need to be?
We produce several pumping systems, in the case of single pump effluent systems, the rising main would be 50mm MDPE, twin pump effluent and domestic sewage systems will use either 63mm, 90mm or 110mm MDPE dependant on the pump specification selected.Top
What is the slowest flow rate I can pump at?
The minimum flow rate is determined by the rate required to achieve ‘self cleansing’ of the rising main, this is generally a velocity of 1.2m/s and the actual flow that this produces depends on the cross sectional area of the rising main.Top
How do I fit my pump?
There are three ways in which pumps are fitted within the ETS range of systems.
1. There are flexible hoses used on small effluent systems. These pumps may be fitted to the flexible hose, lowered into the pump well of the attached rope and secured at the pump manifold, normally on a ‘Camlock’ type hose connector.
2. There are rigid pipe systems. These use ABS or PVC internal pipework, connected directly to the pump with a coupling at the top of this pipe. These will normally be lowered into the chamber with the pipe already connected, again with the weight of the pump supported by the attached rope.
3. There are systems where the pump has one part of an ‘auto-coupling’ set mounted, generally by a flange connection, to the pump. At the bottom of the chamber and connected to the internal rising main is the 2nd half of the ‘auto-coupling’ set (ducks foot). There is a guide rail system installed with mounting brackets at the top of the tank, the guide rails are mounted on the ducks foot. The pump may be hooked onto the guide rail and then lowered onto the auto coupling within the tank. When it reaches the bottom fitting, it latches in such a way as to provide a seal for the pump outlet.
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Is my pump station control panel weather proof?
All panels supplied by ETS are rated as weather proof however, in the interests of security as will as weather protection, it is generally good practice to mount the panel within a locked kiosk.
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Can I pump round 90 degree corners?
Yes, however the tighter the bend, the greater the loss to the potential flow rate. The system will generally include several bends within the chamber itself however, externally to the chamber, it is generally better to use large radius bends.
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How can I prevent septicity?
The most commonly accepted method is to dose the rising main with a chemical (possibly ‘Nutriox’). So the dosing pump has to match the dead head on the sewage pump, not a problem for normal piston type diaphragm pump. Currently we do not supply this type of system.Top
Can I put my unit in the basement?
Yes however, it should be remembered that the chamber will contain sewage, therefore a sealed cover and adequate ventilation should be installed. Careful consideration to the servicing and occasional tankering should be made and it may be necessary to safeguard against flooding.
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Can I have multiple inlets and at different positions?
Yes, however it is important to ensure that the lowest inlet has sufficient depth below it to meet both the pump operational requirements and storage capacity requirements for the application. Consideration to the mounting positions of the float switches with respect to the inlet positions should be made as disturbance to the liquid will effect the correct operation of the system.Top