Comparing the S & Z series metering pumps, the Z series offers more features than the S Series where they overlap, although most of the Z series pumps have higher flow and pressure capabilities compared to the S series.
The S Series solenoid metering pumps by Wanner Engineering are for the most common, lower flow and pressure chemical metering applications. The least expensive design provides a manual dial stroke control and the more expensive models provide full pulse-in control and analog control to set the pulse frequency from an external source.
The price range for S Series solenoid pumps is $350 to $2,290 depending upon materials of construction.
There is some overlap between the S Series and Z Series metering pumps (below); pricing and features are similar however the S Series has a broader range of materials to choose from and for our International customers, can be provided with optional EU or UK compatible power plugs.
This series of metering pumps consists of three models with each available in either constant, proportional or timed dosage configurations. The Z series style pump are relatively inexpensive ($500-$1,100) and is comprised of a control unit that houses the electronics and magnet, and a diaphragm in contact with the liquid to be dosed. These are not self-priming pumps, you must initially prime the pump chamber before dosing will begin. Although they can be used for water, most applications for this style metering pump are for chemical products such as Sulphuric Acid. The body and connectors are made of PVDF, the diaphragm is made of PTFE and the check balls are made of ceramic.
The Z Series metering pumps are energy efficient using solenoids which only draw the power required for the given flow rate and pressure. The digital interface version's intelligent display enable intuitive programming in as many as five languages.
This series of metering pumps consists of six models and are capable of high pressures. The P series is a completely different style of metering pump than the S and Z series style solenoid driven metering pumps. The P series is based upon the Wanner Engineering Hydra-Cell™ design, using one or more hydraulically balanced diaphragms to precisely dose fluids in compliance with API 675 performance standards of linearity, repeatability and accuracy.
Thus the P Series metering pumps have a broader application base, not only due to their higher pressure capabilities but also due to their sealless design which lends itself to pumping viscous, abrasive and other "difficult to handle" fluids such as isocynates, polyols, blowing agents, catalysts, acids and de-ionized water.
Unlike the commodity style S and Z Series metering pumps, the P series flow rate is dictated by the shaft speed of the pump motor. The pump motors typically operate at 1800 RPM and a gearbox is used to mechanically reduce the pump shaft speed. The flow rate can only be varied by varying the pump shaft speed, which is typically achieved using a programmable variable frequency drive (VFD). Comprehensive metering control is achieved with our "Control Freak" touch screen PLC and VFD control package.